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PubMed1980

Microsomal mixed-function oxidase and activities of some related enzymes in hyperplastic nodules induced by long-term griseofulvin administration in mouse liver.

Hepatic hyperplastic nodules induced in mice by long-term griseofulvin administration were examined for selected microsomal activities and responses to enzyme inducers. Despite a decrease in microsomal cytochrome P-450 in hyperplastic nodules, aminopyrine N-demethylase was at control levels. Benzopyrene hydroxylase activity was slightly lower in microsomes derived from hyperplastic nodules than in those of control liver. Reduced nicotinamide adenine dinucleotide-cytochrome b5 reductase was at control level, but reduced nicotinamide adenine dinucleotide- and reduced nicotinamide adenine dinucleotide phosphate (NADPH)-cytochrome c reductases and the NADPH-ferricyanide reductase were increased. NADPH-supported lipid peroxidation was lower in microsomes from hyperplastic nodules than in those from control liver, whereas microsomal stearoyl coenzyme A desaturase activity was almost doubled in the nodules. NADPH-cytochrome c reductases isolated and semipurified from hyperplastic nodule and from control liver microsomes showed almost identical affinity for NADPH. Microsomal enzymes of hyperplastic nodules responded readily to phenobarbital induction, but sodium dodecyl sulfate-polyacrylamide gel electrophoresis disclosed differences in the polypeptide patterns in the molecular weight range from 47,000 to 54,000 between microsomes derived from hyperplastic nodules and control livers.

Animals↗

PubMed1977

[Value of scintigraphy in the treatment of single nodules of the thyroid].

The value of radionuclide scanning of the thyroid gland was investigated in 125 patients with solitary thyroid nodules. Fifty-seven of the 95 patients with 'cold' nodules underwent surgery. The incidence of malignant nodules in this group was 16%; therefore surgery is recommended for all solitary 'cold' nodules. Of the 30 patients with 'warm' nodules, 20 were treated surgically and in only 1 patient was the nodule malignant. This incidence is probably not significant. Surgery is, however, also recommended for all solitary 'warm' nodules because of the possibility of toxic change. Accurate planning of the surgical procedure depends on any function of the nodule in question and this can be determined with certainty only by radionuclide scanning.

Humans↗

PubMedDate not supplied

Small hepatic nodules surrounding hepatocellular carcinoma.

BACKGROUND/AIMS: We investigated whether or not small hepatic nodules surrounding the main hepatocellular carcinoma were malignant, while also analyzing the role of intraoperative ultrasonography in detecting these small nodules. MATERIALS AND METHODS: Thirty-three small hepatic nodules near the main tumor in 17 patients were retrospectively studied. They were first detected either during or after the operation using intraoperative ultrasonography and/or after examining a cross-section of the resected specimen. RESULTS: Twenty-six of the 33 small nodules were shown to be malignant when studied histologically (79%). The reliability of intraoperative ultrasonography was higher than 80 per cent for detecting nodules measuring more than 5 mm in diameter. However, it was only 25 per cent reliable with smaller nodules measuring less than or equal to 5 mm. CONCLUSIONS: These results suggest that most small hepatic nodules with hepatocellular carcinoma should be considered to be malignant. In addition, smaller nodules measuring less than 5 mm in size can hardly be detected by intraoperative ultrasonography.

Carcinoma, Hepatocellular↗

PubMedDate not supplied

[Role of the Doppler technique in the differential diagnosis of solid breast nodules. Personal experience].

The role of Doppler techniques in the differential diagnosis of benign from malignant solid breast lesions remains to be defined; indeed, it is still debated whether the diagnostic findings of Doppler US add further information to mammographic and B-mode US results. We investigated the diagnostic effectiveness of Doppler techniques in the differential diagnosis of breast nodules, especially in a selected group of patients with questionable diagnosis because of atypical morphological features or benign appearance detected in women over 40 years old. Color Doppler studies were performed on 111 breast nodules with solid features at US; 53 vascularized lesions were also studied with duplex Doppler. All the nodules were submitted to biopsy, which demonstrated 6 nonvascularized lesions to be complicated cysts. There were 105 solid breast nodules (65 benign and 40 malignant). Color Doppler US showed vascular signals in 71% of benign nodules, mainly at the periphery. 12% of benign nodules had Doppler signals of malignancy at color Doppler US; 92% of malignant lesions was vascularized, with irregular intratumoral signals in 37% of them. The peak systolic velocity and the resistive index were higher in malignant tumors (p < 0.02); peak systolic velocity changed in malignant lesions according to tumor size (p < 0.01). Color Doppler correctly suspected malignancy in 62% of the nodules with questionable features; conversely, 31% of the nodules with questionable findings and no color Doppler signs of malignancy proved malignant at biopsy. In conclusion, the role of Doppler studies remains currently limited in the differential diagnosis of solid breast lesions.

Adolescent↗

PubMed2025

Partners in root nodule symbiosis respond uniquely to heavy metal stresses in a host genotype-dependent manner.

The mutualistic symbiosis between legume roots and soil rhizobia culminates in the formation of root nodules, where nitrogen is fixed. Root nodule symbiosis is inhibited by heavy metal stress. In this study, we investigated the relative responses of the symbiotic partners to a non-essential heavy metal cadmium (Cd) and an essential heavy metal zinc (Zn) stress and identified patterns in gene expression. We performed dual transcriptomics in nodules, using the Medicago truncatula-Sinorhizobium meliloti symbiotic system. Phenotypes were measured in the wild-type Medicago truncatula and a mutant in an ABC transporter gene (Mtabcg36), which showed compromised nodule formation in control conditions and further after heavy metal treatment. We observed that the rhizobia were particularly sensitive to Zn in mutant nodules. The greatest degree of differential gene expression in the host plant were observed under Cd and Zn treatments in wild-type nodules. Most Cd-regulated host genes were also differentially regulated by Zn, revealing little discernment between an essential and a non-essential ion under increased exposure. Furthermore, the host response to both the stresses affected auxin and iron homeostasis genes in a host genotype-dependent manner. Our results suggested impaired cadmium export from the mutant nodules. These results have potential implications in agricultural management systems and bioremediation strategies.

Symbiosis↗

PubMed2003

Cytologic distinction of goiterous nodules from morphologically normal thyroid: analyses of cytomorphologic features.

BACKGROUND: Fine-needle aspiration (FNA) is the predominant method for triaging thyroid nodules into operative and nonoperative lesions. Accurate needle placement assuring representative sampling of a suspicious nodule is required. Criteria are well established for separation of nodular goiter from most neoplasms but are less well developed for recognition of normal thyroid tissue. Identification of normal tissue is vital when investigating solitary nodules. Cytologic identification of only normal thyroid tissue would indicate a failure to sample the index nodule. The authors investigated a set of criteria to determine whether any were useful for separating goiterous nodules from normal thyroid tissue. METHODS: FNA specimens from 10 patients with histologically confirmed goiters were compared with bench aspirates from 7 nodular goiters and 9 thyroid specimens that showed no histologic change. The three sets of specimens were scored for 21 cytomorphologic variables, and differences in the frequency of the variables between sets of FNA specimens were recorded. The patient specimens were compared with bench specimens to find differences secondary only to in vivo and in vitro specimen types. These features were excluded from analysis of differences between bench specimens of hyperplastic nodules and normal tissue. RESULTS: Cells with feathered cytoplasmic edges occurred with statistically significantly different frequency between bench specimens and patient goiter specimens. Cytomorphologic features that showed differences between FNA specimens from goiters and normal thyroid tissue included the presence of microfollicles, prominent nucleoli, abundant cytoplasm, the number of cells with paravacuolar granules, the presence of Hürthle cells, and the presence of cells with feathered cytoplasmic edges. CONCLUSIONS: The results of the current study indicate that there are cytologic differences between FNA specimens from normal thyroid and from goiterous nodules. The presence of Hürthle cells, prominent nucleoli, and cells with abundant cytoplasm favored the diagnosis of nodular goiter, whereas large numbers of cells with paravacuolar granules favored a determination of histologically normal thyroid. These differences may aid in the distinction of normal thyroid tissue from hyperplastic goiters in cytologic specimens obtained by FNA.

Biopsy, Needle↗

PubMed2002

Diagnosis and management of patients with thyroid nodules.

Fewer than 5% of all adults will have a palpable thyroid nodule, but this is still a large number of individuals who require evaluation. Although most thyroid nodules are a result of a benign disease process (more than 95%), the possibility of thyroid cancer is always a consideration. Important aspects of history taking with a patient in whom a thyroid nodule has been noted include age, gender, family history of thyroid or endocrine disease, prior low dosage head and neck radiation, recent hoarseness, dysphagia, and symptoms of hypermetabolism. Key features of evaluation by physical examination are the size and location of the thyroid abnormality, the degree of firmness of the nodule, the presence of other nodules in the thyroid, palpable cervical lymph nodes, vocal cord paresis or paralysis, and tachycardia and/or tremor. The major categories of thyroid abnormality in such patients include cysts, adenomas, thyroiditis, and cancer. Although radionuclide scans, ultrasound examination and computer tomography have all been employed in the assessment of thyroid nodules, and thyroid stimulating hormone assay is useful for confirming a euthyroid state, fine needle aspiration biopsy (FNAB) has proved to be the most efficient diagnostic tool. The findings from FNAB allow avoidance of operative treatment for a large portion of these patients with palpable thyroid nodules, but a diagnosis of "follicular neoplasm" on FNAB usually requires operation, despite the fact that many such patients do ultimately prove to have a benign lesion. The extent of operation in patients undergoing surgery will depend on the diagnostic findings before operation, but unilateral thyroid lobectomy is the minimum procedure when surgery is required.

Adult↗

PubMed2006

Natural history of thyroid nodules in survivors of pediatric Hodgkin lymphoma.

BACKGROUND: Survivors of Hodgkin lymphoma and other patients who receive neck irradiation are at increased risk of thyroid cancer. Ultrasonography provides an inexpensive and non-invasive method of thyroid screening, but the clinical significance of thyroid nodules detected by ultrasound screening is uncertain. PROCEDURE: We reviewed the demographics, clinical characteristics, method of detection, and outcome of patients who developed thyroid nodules after treatment for pediatric Hodgkin lymphoma at our institution. One radiologist reviewed all imaging studies. RESULTS: Sixty-seven children treated for Hodgkin lymphoma from 1962 to 2001 developed thyroid nodules. The study group represented 9,024 person-years of follow-up after the diagnosis of Hodgkin lymphoma and 581 person-years after diagnosis of a thyroid nodule. A median of 10.5 years (range, 0.2-24.8 years) elapsed between the diagnoses of Hodgkin lymphoma and thyroid nodule(s). All but one patient had received neck irradiation for Hodgkin lymphoma, with a median thyroid radiation dose of 35 Gy (range, 12-45 Gy). Thyroid nodules were found to be malignant in seven patients (10%), at a median of 16.2 years (range, 8.4-23.7 years) after diagnosis of Hodgkin lymphoma. Only one malignancy was found through screening ultrasonography. All patients with thyroid cancer remained disease-free at 0.4-16.2 years of follow-up. CONCLUSIONS: Thyroid nodules are common in Hodgkin lymphoma survivors treated with neck irradiation, but the majority of these lesions have an indolent clinical course and do not undergo malignant transformation. Only patients with a palpable mass or clinical symptoms need more extensive evaluation, including Doppler-flow ultrasonography and fine-needle aspiration.

Disease-Free Survival↗

PubMed2003

Inflammatory pulmonary nodules in Kawasaki disease.

Symptomatic pulmonary manifestations of Kawasaki disease (KD) are uncommon. However, epidemiologic, radiologic, and histologic studies have indicated that respiratory symptoms and findings occur in KD and suggest that the KD agent may have a respiratory portal of entry. We report on three young infants with KD who developed pulmonary nodules, in addition to coronary artery aneurysms. Two patients had pathologic specimens available, one from biopsy and the other from autopsy. The nodules had predominantly mononuclear cell infiltrates, which were within the lung parenchyma and infiltrating vessel walls. Immunohistochemical studies of the nodules, using antibodies to common leukocyte antigen (LCA) and factor VIII-related antigen, confirmed the inflammatory nature of the lesions and showed capillary proliferation. IgA plasma-cell infiltration was observed in the nodule, consistent with previous KD findings of IgA plasma-cell infiltration in the vessel walls, kidneys, pancreas, and upper respiratory tract. The two patients with nonfatal KD were treated with intravenous immunoglobulin and aspirin, with resolution of the nodules. We propose that when pulmonary involvement occurs in KD, it ranges from subclinical interstitial micronodular infiltrates to larger inflammatory pulmonary nodules. These pulmonary infiltrates and nodules likely reflect the host response to the etiologic agent of KD, and may resolve with the disease process. Recognition of this pulmonary complication of KD may enable cautious observation of such lesions for spontaneous resolution.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMedDate not supplied

Hashimoto's thyroiditis presenting as single hot nodule and hypothyroidism.

Radionuclide thyroid scanning of patients with Hashimoto's thyroiditis (HT) may mimic other thyroid disorders including cold nodules, multinodular goiter and rarely hot nodules. The association of single hot nodules in such patients in the face of primary hypothyroidism has not been previously reported. We describe 6 female patients with HT who presented either with symptoms of overt thyroid failure or a sensation of lump in the neck (and later found to have mild thyroid failure) who had single firm thyroid nodules. These nodules were hot by both 99mTc pertechnetate and radioiodine thyroid scans. In three of 4 patients followed up for longer than 6 months on adequate thyroid replacement therapy the nodules regressed by up to 60%. Given "Best practice" recommendations patients with thyroid failure and single thyroid nodules would not be submitted to radionuclide scanning and this presentation of HT would have gone undetected.

Adult↗

PubMed1998

Thyroid nodules in recurrent multinodular goiters are predominantly polyclonal.

Not only thyroid adenomas and carcinomas, but also the majority of single and well delimited goiter nodules, even if morphologically heterogeneous, are of clonal origin. However, it is still unknown whether the nodules of rapidly growing, recurrent goiters are clonal or polyclonal. We investigated by PCR-based analysis of exon 1 of the human androgen receptor gene clonality of nodules grown in recurrent multinodular goiters (MNG) of 14 female patients. The total goiter volume varied widely between 15 ml and 170 ml. The mean age of patients undergoing surgery for recurrent goiter at the time of their first operation was significantly lower with 34.6 +/- 10.9 yr in comparison to 50 consecutive patients who were operated for MNG for the first time (53.7 +/- 13.5 yr). The interval between first and recurrent operation was 18 +/- 8.5 yr. The mean volume of well circumscribed nodules selected for the present investigation was 3.8 +/- 1.4 ml. Assessment of clonality in at least 2 samples of each lesion revealed a polyclonal pattern in 10 out of 14 nodules, whereas only 3 nodules were clonal and in one case the result remained unclear. The unexpected finding that most nodules within MNG, that had re-grown after a first subtotal thyroidectomy, were of polyclonal rather than clonal composition, suggests that these lesions are generated by de novo-proliferation of cohorts of differing thyrocytes sharing the common trait of an exceedingly high intrinsic growth rate or alternatively, by unknown growth stimulating molecular events acting focally on clusters of cells derived from different ancestors. In addition, the relatively young age of patients with recurrent MNG at the time of their first surgery and the comparatively short interval between first and second operation point to a genetic element in the occurrence of growth-prone thyrocytes.

Adult↗

PubMed2005

Gray-scale three-dimensional sonography of thyroid nodules: feasibility of the method and preliminary studies.

The aim of the study was differential evaluation of new and classical sonographic features of benign thyroid nodules and thyroid cancer with three-dimensional gray-scale sonography and evaluation of the effectiveness of the thin-slice surface rendered images in comparison with multiplanar reformation (MPR) presentation. Fifty-four thyroid nodules were interactively evaluated with thin-slice smooth surface rendering: shape in the c-plane (parallel to the probe) and evaluation of echogenicity, margins and calcification/microcalcification-like echogenic foci in the a-plane (plane of the probe). Evaluation of the level of agreement in readers' interpretation and between sonographic techniques was performed using the kappa statistic. Surface rendering permitted visualization of the shape of the nodule in the c-plane in all cases, in contrast to only up to 48% of cases in MPR evaluation. Lobulated nodule shape in the c-plane was 82-100% sensitive and 47-53% specific in diagnosis of carcinoma. Surface rendered images showed more calcification/microcalcification-like echogenic foci than MPR ones. The level of agreement between the observers in the evaluation of features of thyroid nodules and the agreement between features of thyroid nodules on MPR and surface-rendered images showed at least moderate reproducibility (kappa>or=0.41). Three-dimensional thin-slice surface rendering sonography appears to be a feasible and effective method for thyroid nodule evaluation.

Adult↗

PubMed2005

A strategy for thoracoscopic resection of small pulmonary nodules.

BACKGROUND: Preoperative procedures are often necessary to localize pulmonary nodules during thoracoscopic resection in order to reduce the necessity of resorting to thoracotomy. The aim of this report is to describe the strategy we developed to limit preoperative techniques without reducing the thoracoscopic success rate of localization. METHODS: Between January 2000 and December 2003, 183 patients underwent video thoracoscopic resection of small pulmonary nodules. The patients were divided into two groups on the basis of the radiological features of the nodule. The subjects in group 1 were operated on directly, and endothoracic ultrasonography was performed when necessary. The subjects in group 2 underwent preoperative radionuclide labeling of the nodule. RESULTS: In group 1, 112 out of 119 nodules (94%) were localized. Twenty-five out of 32 lesions, neither visible nor palpable, were found by endothoracic ultrasonography. In group 2, we localized 62 out of 64 nodules (97%). CONCLUSIONS: Currently, we cannot completely avoid preoperative labeling techniques for thoracoscopic resection of small pulmonary nodules. However, correct patient selection may limit this necessity, without an increased conversion rate to thoracotomy, if endothoracic ultrasonography is available.

Adolescent↗

PubMed2005

Corticosteroid injections reduce size of rheumatoid nodules.

BACKGROUND: Symptomatic rheumatoid nodules are frequently surgically treated. Injection with steroids might be an alternative treatment. PATIENTS AND METHODS: To determine whether injection with triamcinolon acetonide reduces the size of rheumatoid nodules, we randomized twenty patients with symptomatic nodules to either triamcinolon acetonide 40 mg/ml plus lidocaine 2% or lidocaine 1% (placebo). We measured the nodules before injection and 2, 4, 8, and 12 weeks after injection. Possible side effects were recorded. RESULTS: We found that the volume of the nodules injected with triamcinolon acetonide reduced significantly (p = 0.011), from 130 to 8 mm(3) (median calculated size) at 12 weeks, compared with baseline. Furthermore, at 12 weeks, the difference between the groups was significant (p = 0.03). The median size of the placebo nodules diminished as well, from 358 to 237 mm(3), but this was not significant. Pain at injection was the only side effect, equally distributed in both treatment groups. CONCLUSION: Injection with triamcinolon acetonide seems to be an alternative for surgery of rheumatoid nodules. No adverse events occurred but the limited sample does not allow definitive conclusions.

Anesthetics, Local↗

PubMed1993

Thoracoscopy for the diagnosis of the indeterminate solitary pulmonary nodule.

Traditional nonoperative diagnostic approaches to the indeterminate solitary pulmonary nodule include bronchoscopy and percutaneous needle biopsy. Although both methods are minimally invasive, the diagnosis of the small, peripheral nodule may remain elusive. Open thoracotomy is often required when these methods fail to obtain a diagnosis. Between January 1991 and June 1992, 242 patients with indeterminate solitary lung nodules underwent thoracoscopic excisional biopsy as the primary diagnostic method. Wedge excisions of the nodules were all performed by thoracoscopic techniques using an endoscopic stapler alone (72%), neodymium:yttrium-aluminum garnet laser (18%), or both (10%). A definite diagnosis was obtained in all patients. Two patients required conversion to thoracotomy to locate the nodule (both malignant). A benign diagnosis was obtained in 127 patients (52%) and a malignant diagnosis in 115 (48%). Of the malignant nodules, 51 (44%) were primary lung cancer and 64 (56%) were metastases. All patients diagnosed with primary lung cancer having adequate pulmonary reserve (n = 29) underwent formal open lung resection during the same procedure. There was no mortality, and significant morbidity was limited to atelectasis in 3 patients (1.2%), pneumonia in 2 patients (0.8%), and prolonged air leak more than 7 days in 4 patients (1.6%). Average hospital stay for patients having thoracoscopy only (n = 213) was 2.4 days (range, 1 to 12 days). Thoracoscopy offers a minimally invasive approach for the diagnosis of the indeterminate solitary nodule. It has advantages over traditional diagnostic methods of being virtually 100% sensitive and 100% specific with no mortality and minimal morbidity.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1992

Solitary thyroid nodules in 71 children and adolescents.

Seventy-one children and adolescents with a solitary nodule of the thyroid gland were seen over a 27-year period and all had their nodules removed surgically. All of the patients had preoperative thyroid scintiscans, 55 of which showed a cold nodule. The most common cause of solitary thyroid nodules was follicular adenoma. Fourteen of the 55 cold nodules were malignant (25.5%) while no malignancies were present in warm or hot nodules. Available diagnostic methods for attempting differentiation of benign from malignant solitary nodules are reviewed and recommendations to their clinical management as derived from our experience are presented.

Adolescent↗

PubMed1987

Quantitative computed tomography evaluation of benign solitary pulmonary nodules.

A retrospective evaluation of stable solitary pulmonary nodules was completed in 14 patients using a GE 8800 CT scanner and the Computerized Imaging Reference Systems, Inc., computed tomography chest phantom. Patients with a stable nodule for at least 24 months and no evidence of calcification within the nodule by plain radiography were selected for the study. Using the phantom, a quantitative assessment of nodule density was done in each patient. Of 14 nodules, five were categorized as benign. Linear conventional tomography was performed on these five patients, and only one had evidence of benign calcifications. All patients lived in an area endemic for Coccidioides immitis and six of 14 had culture, serologic, or skin test evidence of previous infection with C. immitis. Two of these six patients had nodules that were characterized as benign using the computed tomography chest phantom. This study indicates that the computed tomography chest phantom is useful in identifying benign nodules in patients living in an area endemic for C. immitis pulmonary infections.

Adult↗

PubMed2005

Computer-aided diagnosis of the solitary pulmonary nodule.

RATIONALE AND OBJECTIVES: We sought to investigate the utility of a computer-aided diagnosis in the task of differentiating malignant nodules from benign nodules based on single thin-section computed tomography image data. MATERIALS AND METHODS: Eighty-one thin-section computed tomography data sets of solitary pulmonary nodules with proven diagnoses (48 malignant and 33 benign) were contoured manually on a single representative slice by a thoracic radiologist (>10 years of experience). Two separate contours were created for each nodule, one including only the solid portion of the nodule and one including any ground-glass components. For each contour 75 features were calculated that measured the attenuation, shape, and texture of the nodule. These features were than input into a feature selection step and four different classifiers to determine if the diagnosis could be predicted from the feature vector. Training and testing was conducted in a resubstitution and leave-one-out fashion and performance was evaluated using ROC techniques. RESULTS: In a leave-one-out testing methodology the classifiers resulted with areas under the ROC curve (A(Z)) that ranged from 0.68 to 0.92. When evaluating with resubstitution the A(Z) ranged from 0.93 to 1.00. CONCLUSION: Computer-aided diagnosis has the potential to assist radiologists in the task of differentiating solitary pulmonary nodules and in the management of these patients.

Diagnosis, Differential↗