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PubMed1999

[The treatment of solitary thyroid nodules in non-toxic goiter with 96% ethanol injections].

40 patients (39 women and 1 man) aged 13-66 years (mean 35.9 years) with solitary benign non-toxic thyroid nodule confirmed by clinical and hormonal examination, ultrasonography and fine needle aspiration biopsy, were treated with intranodular percutaneous 96% ethanol injection, performed under ultrasound guidance. There were 34 patients with solid nodule (including 4 patients) with solitary nodule in recurrent goitre after thyroidectomy) and 6 patients with cyst. The nodules were 7-60 mm (mean 31 mm) in diameter. 1 ml of ethanol was instilled per 1 cm3 of nodule tissue. 1-5 (mean 2.6) sessions were conducted at one month intervals. The early follow-up evaluation of the results (the evaluation of nodule size by means of clinical and ultrasound examination) was performed after 6 months, and the long-term one after 2 years since the last injection. A morphological evaluation was conducted according to the following scale: 1--nodule disappearance, 2--cicatricial nodule (solid structure in the ultrasonography and less than 0.5 cm in diameter), 3--nodule smaller by [symbol: see text] 50% of initial dimensions, 4--nodule smaller by < 50% of initial dimensions. A final follow-up evaluation revealed: nodule disappearance in 15 (37.5%) patients (Group 1), cicatricial nodule in 10 (25%) patients (Group 2), nodules smaller by [symbol: see text] 50% of initial dimensions in 7 (17.5%) patients (Group 3) and nodules smaller by < 50% of initial dimensions in 8 (20%) patients (Group 4). The results in Group 1 and 2 were defined as good (25 patients--62.5%), in Group 3 as satisfactory (17.5%) and in Group 4 as bad. The results of treatment of cysts and nodules in recurrent goitre were good or satisfactory. The following complications were observed: 1) pain during and after the injection in 29 (72.5%) patients, 2) subfebrile body temperature ap to 38 degrees C in 4 (10%) patients and fever up to 39 degrees C on the 1-st day after the injection in 2 (5%) patients, 3) ecchymosis in 1 (2.5%) patient, 4) temporary dysphonia in 2 (5%) patients, 6) temporary unilateral vocal cord paralysis and temporary Horner syndrome in 1 (2.5%) patient. It seems that percutaneous ethanol injection can be useful treatment method of solitary benign non-toxic thyroid nodules, both cysts and solid nodules, in patients who do not consent to surgical treatment or with contraindications to an operation.

Adolescent↗

PubMed2003

The clinical significance of an isofunctioning thyroid nodule.

The management of an "isofunctioning" thyroid nodule--defined by radioiodine uptake equivalent to normal thyroid tissue--is often a dilemma. Our goal was to determine the percentage of thyroid nodules that were isofunctioning and the frequency with which carcinoma occurred in an isofunctioning nodule. Patients referred for evaluation of a thyroid nodule from 1990 to 2002 were reviewed and those with an iodine-123 thyroid scintiscan were identified. Nodule size, serum thyrotropin, fine-needle aspiration biopsy, pathology, and follow-up were determined for patients with an isofunctioning, hypofunctioning, or hyperfunctioning thyroid nodule. Of the 562 patients with a thyroid nodule 273 (49%) had a thyroid scan. Nodules were hypofunctioning in 232 (85%), isofunctioning in 29 (11%), and hyperfunctioning in 12 (4%) patients. Mean nodule size and serum thyrotropin level were respectively 2.49 +/- 0.23 cm and 1.73 +/- 0.26 microIU/mL for isofunctioning, 2.47 +/- 0.31 cm and 0.83 +/- 0.21 microIU/mL for hyperfunctioning, and 3.94 +/- 0.13 cm and 1.86 +/- 0.28 pIU/mL for hypofunctioning nodules. Seventeen patients with an isofunctioning nodule underwent thyroidectomy and 12 patients were followed for a mean 27 months without an increase in nodule size. No patient with a hyperfunctioning nodule, six patients (21%) with an isofunctioning nodule, and 44 patients (19%) with a hypofunctioning nodule had a carcinoma. We conclude that the risk of malignancy in an isofunctioning nodule is similar to that of a hypofunctioning nodule and therefore the management should be based on routine fine-needle aspiration biopsy.

Algorithms↗

PubMed2004

Evaluation of F-18 fluorodeoxyglucose (FDG) PET scanning for pulmonary nodules less than 3 cm in diameter, with special reference to the CT images.

BACKGROUND: While pulmonary nodules can be substantially divided into solid and ground-glass opacity (GGO) ones on CT image, they have different biological natures which could cause false positive or false negative to diagnose malignancy on positron emission tomography with fluorodeoxyglucose (FDG-PET). To determine the effectiveness of PET for small pulmonary nodules, the nodules were classified into solid and GGO ones, of which results were compared with the data of PET scans. The lower limit size of nodules for PET imaging was also evaluated. METHODS: Prospective FDG-PET scans were undertaken for 136 non-calcified nodules less than 3 cm in diameter. CT density histograms were made for each nodule to classify into solid and GGO ones. RESULTS: Eighty-one nodules were malignant and 55 were benign. All of the 20 nodules less than 1 cm in diameter (n = 8 in malignant, n = 12 in benign), were negative on PET regardless of the histology. In the 116 nodules 1-3 cm in diameter (n = 73 in malignant, n = 43 in benign), there were 15 false negative and 15 false positive nodules, with a sensitivity of 79% and specificity of 65%. CT density histograms showed 101 solid nodules (n = 63 in malignant, n = 38 in benign) and 15 GGO nodules ( n = 10 in malignant, n = 5 in benign). All of the 10 malignant nodules with GGO images were histologically well-differentiated adenocarcinoma and 9 of them (90%) were false negative on PET. Four of the 5 (80%) benign nodules with GGO images were focal pneumonia with well-preserved air spaces, causing false positive on PET. Sensitivity and specificity for nodules with GGO images were 10 and 20%, respectively, which were significantly lower than 90 and 71% for nodules with solid images (P < 0.001). CONCLUSION: Pulmonary nodules which are less than 1cm in size or show GGO images on CT cannot be evaluated accurately by PET.

Adenocarcinoma↗

PubMed1980

Effect of light, dark, and temperature on root nodule activity (acetylene reduction) of soybeans.

The objectives of this study were (a): to define the effects of light, dark, and temperature on nodule activity (acetylene reduction), and (b) to establish the contributions of reserve carbohydrate and recent photosynthate to the support of nodule function. An in situ assay of nodule activity was developed for use with intact, hydroponically grown soybeans (Glycine max [L.] Merr. cv. Calland).Nodule activity of 35-day-old plants grown in controlled environment chambers decreased during a 10-hour dark period at 18 C, compared with activity during the preceding and subsequent 14-hour light periods at 27 C. In contrast, plants that were maintained at a constant 27 C did not vary in nodule activity during diurnally varying dark and light exposure. Nodules of plants exposed to diurnal 18 and 27 in 24-hour continuous dark were less active at 18 C than at 27 C. At constant 27 C, nodule activity was sustained throughout the 24-hour dark period. Thus, nodule activity was independent of short term dark periods but dependent on temperature; nodule activity was decreased at the lower temperature.Temperature also affected the nodule activity of plants maintained in the light. Exposure of shoots and roots of intact plants to the lower temperature (5 hours at 18 C) during the light period resulted in a marked decrease in nodule activity, compared with that of plants maintained at 27 C. Exposure of only the shoot portion to 18 C (roots were maintained at 27 C) resulted in a similar decrease in nodule activity.Nodules of plants exposed to 10 days of diurnally variable dark, light, and temperature had high activity in the light at 27 C and low activity in the dark at 18 C. Nodule activity of plants at a constant 27 C was not affected by diurnally variable dark and light exposure throughout the 10-day period, although activity generally increased with time due to increased nodule mass. At a constant 27 C, nodules of intact plants in continuous dark sustained activity through 72 hours before declining to zero by 7 days. At diurnally varying 18 and 27 C in continuous dark, peak diurnal nodule activity was sustained through 5 days, and then declined to zero by 8 days. Analyses of the carbohydrate content of tissue harvested from this study suggested use of reserve photosynthate (primarily of shoot origin) in support of nodule activity in the absence of concurrent photosynthesis.

Journal Article↗

PubMed1987

Nonphotosynthetic CO(2) Fixation by Alfalfa (Medicago sativa L.) Roots and Nodules.

The dependence of alfalfa (Medicago sativa L.) root and nodule nonphotosynthetic CO(2) fixation on the supply of currently produced photosynthate and nodule nitrogenase activity was examined at various times after phloem-girdling and exposure of nodules to Ar:O(2). Phloemgirdling was effected 20 hours and exposure to Ar:O(2) was effected 2 to 3 hours before initiation of experiments. Nodule and root CO(2) fixation rates of phloem-girdled plants were reduced to 38 and 50%, respectively, of those of control plants. Exposure to Ar:O(2) decreased nodule CO(2) fixation rates to 45%, respiration rates to 55%, and nitrogenase activities to 51% of those of the controls. The products of nodule CO(2) fixation were exported through the xylem to the shoot mainly as amino acids within 30 to 60 minutes after exposure to (14)CO(2). In contrast to nodules, roots exported very little radioactivity, and most of the (14)C was exported as organic acids. The nonphotosynthetic CO(2) fixation rate of roots and nodules averaged 26% of the gross respiration rate, i.e. the sum of net respiration and nonphotosynthetic CO(2) assimilation. Nodules fixed CO(2) at a rate 5.6 times that of roots, but since nodules comprised a small portion of root system mass, roots accounted for 76% of the nodulated root system CO(2) fixation. The results of this study showed that exposure of nodules to Ar:O(2) reduced nodule-specific respiration and nitrogenase activity by similar amounts, and that phloem-girdling significantly reduced nodule CO(2) fixation, nitrogenase activity, nodule-specific respiration, and transport of (14)C photoassimilate to nodules. These results indicate that nodule CO(2) fixation in alfalfa is associated with N assimilation.

Journal Article↗

PubMed1989

Nodulation of Glycine max by Six Bradyrhizobium japonicum Strains with Different Competitive Abilities.

The root nodule locations of six Bradyrhizobium japonicum strains were examined to determine if there were any differences which might explain their varying competitiveness for nodule occupancy on Glycine max. When five strains were added to soybeans in plastic growth pouches in equal proportions with a reference strain (U.S. Department of Agriculture, strain 110), North Carolina strain 1028 and strain 110 were the most competitive for nodule occupancy, followed by U.S. Department of Agriculture strains 122, 76, and 31 and Brazil strain 587. Among all strains, nodule double occupancy was 17% at a high inoculum level (10 CFU pouch) and 2% at a low inoculum level (10 CFU pouch). The less competitive strains increased their nodule representation by an increase in the doubly occupied nodules at the high inoculum level. Among all strains, the number of taproot and lateral root nodules was inversely related at both the high and low inoculum levels (r = -0.62 and -0.69, respectively; P = 0.0001). This inverse relationship appeared to be a result of the plant host control of bacterial infection. Among each of the six strains, greater than 95% of the taproot nodules formed at the high inoculum density were located on 25% of the taproot length, the nodules centering on the position of the root tip at the time of inoculation. No differences among the six strains were observed in nodule initiation rates as measured by taproot nodule position. Taproot nodules were formed in the symbiosis before lateral root nodules. One of the poorly competitive strains (strain 76) occupied three times as many taproot nodules as lateral root nodules when competing with strain 110 (nodules were harvested from 4-week-old plants). Among these six wild-type strains of B. japonicum, competitive ability evidently is not related to nodule initiation rates.

Journal Article↗

PubMed1990

Competitive Ability and Efficiency in Nodule Formation of Strains of Bradyrhizobium japonicum.

In the American Midwest, superior N(2)-fixing inoculant strains of Bradyrhizobium japonicum consistently fail to produce the majority of nodules on the roots of field-grown soybean. Poor nodulation by inoculant strains is partly due to their inability to stay abreast of the expanding soybean root system in numbers sufficient for them to be competitive with indigenous bradyrhizobia. However, certain strains are noncompetitive even when numerical dominance is not a factor. In this study, we tested the hypothesis that the nodule occupancy achieved by strains is related to their nodule-forming efficiency. The nodulation characteristics and competitiveness of nine strains of B. japonicum were compared at both 20 and 30 degrees C. The root tip marking technique was used, with the nodule-forming efficiency of each strain estimated from the average position of the uppermost nodule and the number of nodules formed above the root tip mark. The competitiveness of the nine strains relative to B. japonicum USDA 110 was determined by using immunofluorescence to identify nodule occupants. The strains differed significantly in competitiveness with USDA 110 and in nodulation characteristics, strains that were poor competitors usually proving to be inferior in both the average position of the uppermost root nodule and the number of nodules formed above the root tip mark. Thus, competitiveness was correlated with both the average position of the uppermost nodule (r = 0.5; P = 0.036) and the number of nodules formed above the root tip mark (r = 0.64; P = 0.005), while the position of the uppermost nodule was also correlated to the percentage of plants nodulated above the root tip mark (r = 0.81; P < 0.001) and the percentage of plants nodulated on the taproot (r = 0.67; P = 0.002).

Journal Article↗

PubMed2000

Outcomes of dysplastic nodules in human cirrhotic liver: a clinicopathological study.

The number of dysplastic nodules detected clinically has increased since patients with hepatitis virus-associated cirrhosis, who are at increased risk for hepatocellular carcinoma (HCC), began to undergo regular cancer surveillance. Although it is potentially important to determine which type(s) of nodule may be prone to progress to HCC, outcomes of dysplastic nodules have not been fully investigated. This prompted us to examine the outcomes of dysplastic nodules in cirrhotic patients clinicopathologically. We studied 33 dysplastic nodules of <20 mm in maximum diameter, diagnosed by fine needle aspiration biopsy under ultrasonography (US). These nodules were clinically followed, mainly by US examination, for up to 70 months. When the nodules enlarged or exhibited changes on US, they were histologically reexamined by second biopsy. Surprisingly, 15 of the 33 nodules (45.5%) disappeared, 14 nodules (42.4%) remained unchanged, and only 4 nodules (12.1%) progressed to HCC. The latter 4 nodules were all hyperechoic on US and were composed of clear cells with fatty change or small cells with increased nuclear density, and in all 4 patients serum was positive for hepatitis C virus antibody. Univariate analyses revealed that, although not significant, the hyperechoic nodules or nodules with small cell change showed a higher HCC progression rate in comparison with the hypoechoic nodules or the nodules without small cell change. In summary, most of the dysplastic nodules we followed disappeared or remained unchanged, but some progressed to HCC. Hyperechoic nodules in patients with hepatitis C virus-associated cirrhosis, which show small cell change with increased nuclear density, may be prone to progress to HCC.

Adult↗

PubMed1989

Adenine nucleotides and carbohydrates in subpopulations of hepatic nodules with normal and compromised microcirculation.

Fluorescein-isothiocyanate dextran (FITC-dextran), a dye confined to the vascular space, was infused via the hepatic artery and portal vein into perfused livers from fed rats treated with diethylnitrosamine for 4 to 5 months. Fluorescence due to FITC-dextran was detected with fiberoptic microlight guides placed on surface nodules of about 5 mm in diameter. Nodules were categorized into groups with normal and compromised microcirculation based on their fluorescence following infusion of FITC-dextran. Similar results were obtained when nodules were classified based on reflectance of trypan blue. Despite compromised microcirculation, ATP and ADP levels as well as ATP/ADP ratios were comparable in both groups of nodules; however, AMP was elevated in FITC-dextran-negative nodules (i.e., those with compromised microcirculation). Nodules with compromised microcirculation also contained higher glucose and lactate levels than nodules that were well perfused; however, glycogen was five times lower than in FITC-dextran-positive nodules. Fasting reduced ATP/ADP ratios in poorly perfused nodules in comparison to well-perfused nodules. In perfused livers from fed rats where glycogen was high, however, ATP/ADP ratios and rates of ATP depletion during ischemia were the same in well-perfused and poorly perfused nodules. Products of glycogen breakdown (e.g., glucose and lactate) were elevated in nodules from livers of fed but not fasted rats. The results indicate that alteration of perfusion of hepatic nodules does not change ATP levels nor the capacity of nodules to utilize high energy phosphate during anoxia. Thus, near normal energy status is maintained from glycogen metabolism in poorly perfused nodules via glycolysis. Since basal ATP content and utilization is comparable in well and poorly perfused nodules, compromised energy status is unlikely to explain selection of nodules that regress to near normal hepatocytes.

Adenine Nucleotides↗

PubMed2005

Pulmonary nodules 10 mm or less in diameter with ground-glass opacity component detected by high-resolution computed tomography have a high possibility of malignancy.

OBJECTIVES: For the histological diagnosis of small lung cancers of 10 mm or less in diameter (< or =10), resection by video-assisted thoracic surgery (VATS) with computed tomography (CT)-guided marking is feasible. One problem is that a small number of these pulmonary nodules are malignant. We retrospectively analyzed CT images of pulmonary nodules to find better criteria to select candidates for resection among patients with small pulmonary nodules. METHODS: Ninety-four patients with indeterminate peripheral pulmonary nodules underwent wedge resection by VATS. High-resolution CT using a 1.25 mm slice included the area of lesions. Nodules were classified by size (< or =10, 11 to 20, >20 mm) and whether they had a ground-glass opacity (GGO) component. RESULTS: The histology of all 94 nodules showed 52 primary lung cancers, 6 metastatic tumors, 5 benign tumors, 8 intrapulmonary lymph nodes, and 23 inflammatory nodules. Ninety-three percent of nodules larger than 20 mm, 75% of nodules 10 to 20 mm, and 43% of nodules < or =10 mm were malignant. Introducing a classification according to GGO component to nodules, malignancy was detected in 88% of nodules with a GGO component and in 30% of nodules without a GGO component among nodules < or =10 mm. Nodules < or =10 mm with a GGO component showed a statistically significant (p < 0.01) correlation with malignancy. CONCLUSIONS: Pulmonary nodules < or =10 mm with GGO should be considered to have a high possibility of malignancy and to be candidates for resection by VATS.

Carcinoma, Small Cell↗

PubMed2006

Current status of fine needle aspiration for thyroid nodules.

When not to perform fine needle aspiration of a thyroid nodule In summary, FNA of thyroid nodules has become one of the most useful, safe, and accurate tools in the diagnosis of thyroid pathology. Thyroid nodules that should be considered for FNA include any firm, palpable, solitary nodule or nodule associated with worrisome clinical features (rapid growth, attachment to adjacent tissues, new hoarseness, or palpable lymphadenopathy). FNA should also be performed on nodules with suspicious ultrasonographic features (microcalcifications, rounded shape, predominantly solid composition); dominant or atypical nodules in multinodular goiter; complex or recurrent cystic nodules; or any nodule associated with palpable or ultrasonographically abnormal cervical lymph nodes. Finally, FNA should be performed on any abnormal-appearing or palpable cervical lymph nodes. The management of thyroid nodules based on FNA findings is summarized in Table 2. It can be argued that in certain circumstances the results of thyroid FNA do not change the surgical management of a thyroid nodule, and thus preoperative FNA may be unnecessary. These cases include solitary nodules in patients who have a strong family history of thyroid cancer, multiple endocrine neoplasia type II, or radiation to the head and neck. These patients when they have thyroid nodules have at least a 40% risk for thyroid cancer and frequent multifocal or bilateral disease and should undergo total thyroidectomy with or without central neck lymph node dissection. Patients who have multinodular goiter and compressive symptoms, patients who have Graves disease and a thyroid nodule, or patients who have large (greater than 4 cm) or symptomatic unilateral thyroid nodules could also be considered for total thyroidectomy or lobectomy as indicated without preoperative FNA. Finally, patients who have a solitary hyperfunctioning nodule on radioiodine scan and a suppressed TSH have an extremely low incidence of malignancy and may be considered for therapeutic thyroid lobectomy or radioiodine ablation as indicated without undergoing FNA biopsy.

Adenoma, Oxyphilic↗

PubMed2002

Indication for preoperative localization of small peripheral pulmonary nodules in thoracoscopic surgery.

OBJECTIVE: Widespread clinical use of helical computed tomography has improved the detection rate for small peripheral pulmonary nodules. As a result, use of thoracoscopic surgery to confirm the diagnosis of small peripheral pulmonary nodules has become more important than ever before. However, if small peripheral pulmonary nodules are too small or located too deeply to detect thoracoscopically, it is necessary to mark the small peripheral pulmonary nodules preoperatively. The purpose of this study was to determine indications for preoperative hookwire marking in thoracoscopic resection of small peripheral pulmonary nodules. METHODS: A total of 120 patients underwent thoracoscopic pulmonary resection in our institute from 1999 to 2001. Small peripheral pulmonary nodules were marked preoperatively in 61 of these patients by means of percutaneous placement of a hookwire under computed tomographic guidance. The hookwire-marked small peripheral pulmonary nodules either were smaller than 10 mm or were located more than 10 mm below the pleural surface. RESULTS: Although 9 of the hookwire-marked small peripheral pulmonary nodules were easily identified during thoracoscopy, the other 52 small peripheral pulmonary nodules could not have been identified during thoracoscopy without the hookwire marking. Of the 59 small peripheral pulmonary nodules that were not hookwire marked, 7 required conversion to thoracotomy to locate the nodules. Small peripheral pulmonary nodules from both groups were examined and assigned to either an undetectable or detectable group. Discriminant function analysis indicated that a linear function (ie, depth = 0.836 x size - 2.811) could be used to differentiate between undetectable and detectable small peripheral pulmonary nodules, and preoperative hookwire marking for small peripheral pulmonary nodules should be considered for nodules in the region above those. CONCLUSION: The results suggest that this formula might serve as an indication for preoperative marking of small peripheral pulmonary nodules in thoracoscopic resection.

Female↗

PubMedDate not supplied

Thyroxine suppressive therapy of benign solitary thyroid nodules: a prospective randomized study.

Patients with solitary thyroid nodules that are benign on aspiration biopsy are often treated nonsurgically. To find out if thyroxine therapy is effective, 74 patients were randomized to receive levothyroxine treatment or nothing. There were 8 males and 66 females. Their mean age was 39 years. The mean nodule size was 3.6 cm and the mean nodule duration was 11 months. All patients had normal serum thyroxine and thyroid stimulating hormone (TSH) levels, and positive thyrotropin releasing hormone (TRH) tests. The dose of thyroxine was adjusted until the TRH test was negative. Patients were followed at 6-month intervals in the first 2 years and yearly thereafter, with measurement of the nodule diameter. The mean follow-up period was 1.5 years. In the 37 patients receiving thyroxine therapy, 8 had disappearance of nodules, 6 had greater than 50% reduction in nodule size. In 19, the nodules were unchanged and in 4, the nodules were enlarged. In the 37 patients receiving no drug, 8 had disappearance of nodules, 5 had greater than a 50% reduction in nodule size, 17 had nodules unchanged, and 7 had enlarged nodules (p greater than 0.9). The mean reduction in nodule diameter at various follow-up periods was greater in the thyroxine group, but the difference did not reach statistical significance. Carcinoma was found in 1 patient in each group and both of them experienced nodule enlargement. We conclude that an adequate suppressive dose of levothyroxine does not alter the natural course of benign solitary thyroid nodules. An enlargement of the nodule or a change in its consistency should be further investigated to exclude malignancy.

Adult↗

PubMedDate not supplied

Dysplastic nodules of the liver: imaging findings.

BACKGROUND: To verify characteristic features of hepatic dysplastic nodules at different imaging modalities. METHODS: Twenty-eight patients with 37 dysplastic nodules of the liver (0.8-3.0 cm) underwent sonography (28 patients), computed tomography (CT; 24 patients), magnetic resonance (MR; 11 patients), and angiography (12 patients). Each nodule was analyzed for echogenicity, attenuation, signal intensity, and vascularity. RESULTS: Echogenicity of nodules was high in 16 (43%), homogeneous in two (6%), and low in 19 (51%) of 37 nodules. Attenuation of nodules was high in one (7%), homogeneous in four (26%), and low in 10 (67%) of 15 nodules on the arterial-phase CT images; homogeneous in five (33%) and low in 10 (67%) of 15 nodules on the portal-phase CT images; and high in four (17%), homogeneous in six (26%), and low in 13 (57%) of 23 nodules on the delayed-phase CT images. Signal intensity of nodules was high in 15 (94%) and homogeneous in one (6%) of 16 nodules on T1-weighted MR images and was homogeneous in seven (44%) and low in nine (56%) of 16 nodules on T2-weighted MR images. Vascularity of nodules was avascular in 14 (88%) and slightly vascular in two (12%) of 16 nodules. CONCLUSIONS: Hepatic dysplastic nodules show diverse imaging characteristics with different imaging techniques; however, common imaging findings of hepatic dysplastic nodules are low echo, low attenuation, and high, low, or homogeneous intensity on T1- and T2-weighted MR, and avascularity.

Adult↗

PubMed2005

Visual and semiquantitative analyses for F-18 fluorodeoxyglucose PET scanning in pulmonary nodules 1 cm to 3 cm in size.

BACKGROUND: While visual assessment is the simplest way to evaluate positron emission tomography (PET) with fluorodeoxyglucose (FDG), faintly positive nodules are often difficult to evaluate. We performed visual and semiquantitative analyses of pulmonary nodules from 1 to 3 cm in size to determine the optimal method of analysis for PET data, especially for faintly positive nodules on visual assessment. METHODS: Positron emission tomography data were analyzed for 161 pulmonary nodules from 1 to 3 cm in size (108 malignant and 53 benign nodules). On visual assessment, FDG uptake by the nodules was classified into three grades in comparison with mediastinal blood pool, (ie, definitely positive, faintly positive, and negative). In addition, FDG uptake was measured by the standard uptake value (SUV), the contrast ratio to the contralateral lung (CR-lung), and the contrast ratio to the cerebellum (CR-brain). Cut-off values for each variable were determined from receiver operating characteristics (ROC) curves, and the values were 2.5 for the SUV, 0.4 for the CR-lung, and 0.25 for the CR-brain. Nodules with FDG uptake above these cut-off values were defined as positive in each method. RESULTS: Visual assessment showed definitely positive for 80 nodules (64 malignant and 16 benign), faintly positive for 22 (17 malignant and 5 benign), and negative for 59 nodules (27 malignant and 32 benign). In the 139 nodules that were definitely positive or negative by visual assessment, there were no significant differences of sensitivity and specificity among the four methods (visual assessment, SUV, CR-lung, and CR-brain). In the 17 malignant nodules that were faintly positive, the SUV did not detect any true-positive nodules, but the CR-lung and CR-brain showed 9 and 5 true-positive nodules, respectively, resulting in a significantly higher sensitivity than the SUV (p < 0.001 and p = 0.02, respectively). Fifteen of 17 faintly positive malignant nodules (88%) were histologically well- or moderately-differentiated adenocarcinoma. CONCLUSIONS: The semiquantitative methods (SUV, CR-lung, and CR-brain) do not improve the efficacy of visual assessment alone for nodules graded as definitely positive or negative. However, faintly positive nodules on visual assessment should be evaluated by the CR-lung or CR-brain rather than the SUV, and are often differentiated adenocarcinomas.

Female↗

PubMed1996

Management of new hepatic nodules detected by intraoperative ultrasonography during hepatic resection for hepatocellular carcinoma.

BACKGROUND: During hepatic resection for hepatocellular carcinomas (HCCs) it is not uncommon that intraoperative ultrasonography detects "new nodules" that were not found by preoperative examinations. Because the operative procedure may have to be changed if the new nodule is another HCC lesion, differential diagnosis of such nodule is critical. This study examines ultrasonographic findings and clinical features of new nodules and discusses how to cope with such nodules in the operating room. METHODS: Fifty-one new nodules detected in 92 liver resections were analyzed. Intraoperative ultrasonography was performed by using 5.0 or 7.5 MHz probes after mobilization of the liver. Histologic diagnosis of the new nodules was made by means of enucleation, resection with the primary lesions, thick-needle biopsy, or additional partial resection of the liver. RESULTS: New nodules were detected in 27 (29.3%) of 92 resected cases. Internal echoic pattern of the nodules were type I, hypoechoic (29 nodules); type II, hyperechoic (19); and type III, mosaic (3). Ten HCC nodules (17.9%) were included, and chance of being malignant for each type was 24.1%, 0%, and 100%, respectively. Of the seven patients with malignant new nodules, three underwent additional systematic resection and all were alive without recurrence 49, 13, and 11 months after the operation. Others were treated by use of enucleation (two cases), intraoperative ethanol injection (one case), and intraarterial chemotherapy (one case). CONCLUSIONS: Although most of the new nodules lacked specific findings for HCC, hypoechoic nodules, 24.1% of which were HCCs, should not be overlooked. Histologic confirmation of the new nodules is necessary especially when the number of lesions detected before operation is multiple or the interval between lipiodol computed tomography and the operation is longer than 2 months. Once the diagnosis of HCC has been made for the new nodule, systematic additional resection to remove the new lesion is recommended.

Adult↗

PubMed2000

Probability of hepatocellular carcinoma of small hepatocellular nodules undetectable by computed tomography during arterial portography.

Recent advances in imaging modalities enable the identification of small hepatocellular nodules. Among the imaging techniques currently used for detecting hepatocellular carcinomas (HCC), computed tomography (CT) during arterial portography (CTAP) is one of the most sensitive techniques available for detecting hemodynamic change. Even so, well-differentiated HCCs that display only limited hemodynamic change, a feature shared with nonmalignant hepatocellular nodules, are not always detectable by CTAP. To improve our ability to distinguish well-differentiated HCCs from nonmalignant hepatocellular nodules, we have attempted to clarify how the characteristics of the nodules are shown by each imaging technique. We studied the imaging and pathological characteristics of 31 nodules (in 22 patients) detected by ultrasonography (US), but not by CTAP. Histological diagnoses were as follows: HCC, 17 of 31 nodules (55%); high-grade dysplastic nodules, 1 of 31 (3%); and nonmalignant nodules, 13 of 31 (42%). Neither digital substraction angiography (DSA) nor CT arteriography (CTA) were able to detect any of the nodules. Detection rates for plain CT were: 5 of 17 (29%) HCC, 1 of 1 (100%) high-grade dysplastic nodules, and 1 of 13 (8%) nonmalignant nodules. Detection rates for T1/T2-weighted magnetic resonance imaging (MRI) were: 4 of 17 (24%) HCC, 1 of 1 (100%) high-grade dysplastic nodules, and 3 of 13 (23%) nonmalignant nodules. Dynamic CT and dynamic MRI provided no additional information. In conclusion, there is some probability that hepatocellular nodules detected by US, but not by CTAP, are HCC. Presently, it is difficult to distinguish between benign nodules and malignant ones with these imaging techniques, and our findings indicate that biopsy may be advisable for nodules detected under these conditions.

Adult↗

PubMed1998

Neoangiogenesis and sinusoidal "capillarization" in dysplastic nodules of the liver.

The blood supply of hepatocellular carcinoma (HCC) is primarily arterial. Recent studies reported differences of vascular, especially arterial, supply among low- and high-grade dysplastic nodules and HCC. We assessed arterialization using monoclonal antibody specific for smooth muscle actin as well as simultaneous changes in sinusoidal capillarization in cirrhotic nodules, dysplastic nodules, and HCC. We immunohistochemically stained 56 cirrhotic nodules, 20 low-grade dysplastic nodules, 27 high-grade dysplastic nodules, and 20 HCCs for alpha smooth muscle actin (to identify unpaired arteries (i.e., arteries not accompanied by bile ducts) and CD34 (indicating sinusoidal capillarization). Distribution and number of unpaired arteries and distribution of sinusoidal capillarization were graded semiquantitatively. Unpaired arteries were rare in cirrhotic nodules, significantly more common in dysplastic nodules of both types (p < 0.00001), and most common in HCC. Sinusoidal capillarization was least common in cirrhotic nodules, significantly more common in dysplastic nodules (p < 0.0035), and most common in HCC. No topographic relationship between unpaired arteries and sinusoidal capillarization was identified. These findings showed that (1) distributions of sinusoidal capillarization and unpaired arteries in dysplastic nodules are intermediate between those in cirrhotic nodules and HCC, supporting dysplastic nodules as premalignant lesions; (2) unpaired arteries are histologically useful for distinguishing dysplastic nodules from large cirrhotic nodules; and (3) areas of sinusoidal capillarization within dysplastic nodules are unrelated to location of arterialization.

Actins↗