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PubMed1975

Transplantation models using the regional lymph node.

Several transplantation models, using the regional lymph node, to study the transplantation reaction in strictly defined and simple conditions were devised. Lymphoid cells were transplanted to inbred rats and mice at the sites drained by one regional lymph node; the experimental design was chosen so as to permit theoretically a one-way reaction, either the host-versus-graft (HVG) or the graft-versus-host (GVH) reaction. The changes in the lymph nodes draining the site of cell injection (weight increase, histology, lymphocyte activation) were very similar in both transplantation reactions. They were ascribed to a humoral mediator released upon the contact of lymphoid cells from two genetically different individuals. The direct demonstration of a mediator which is capable of activating the regional lymph node in vivo introduces some new aspects into the process of sensitization after transplantation.

Animals↗

PubMed2002

Follicular hyperplasia presenting with a marginal zone pattern in a reactive lymph node lesion.

Histologically, the marginal zone pattern of the lymph node is characterized by lymphoid follicles with three distinct layers. The inner layer is composed of follicular center zones, the middle layer of darkly stained mantle zones, and the outer layer of marginal zones. However, the marginal zone pattern is rarely seen in reactive lymph nodes except for mesenteric lymph nodes. We describe the clinicopathologic, immunohistochemical and genotypic findings of six cases of reactive follicular hyperplasia exhibiting the marginal zone pattern. The patients comprised three males and three females (age range 24 to 63 years; medium 56 years). Follow-up data were obtained from five patients. None of them developed malignant lymphomas during the follow-up period of from 5 to 204 months (median 68 months). Histologically, the lesion was characterized by numerous lymphoid follicles and partial distortion of lymph node structure. Varying degrees of progressive transformation of the germinal center (PTGC) were noted in the four cases. The marginal zone pattern was observed in some or most of the lymphoid follicles including PTGC. The marginal zone B cells were small to medium-sized lymphocytes with round or slightly indented nuclei and a broad rim of pale cytoplasm. Some of them had a monocytoid appearance. They were CD20+, CD79a+, sIgM+/-, sIgD-, CD5-, CD10-, CD21-, CD23-, CD43-, CD45RO-, Bcl-6-, cyclin D1-, EMA- and p53-. A portion of them were Bcl-2 positive. Occasional large lymphoid cells with round or indented nuclei and moderate amounts of cytoplasm were observed in the marginal zone in four cases. These large lymphoid cells were usually CD20 positive, but Bcl-6 negative. A small number of them contained polytypic intracytoplasmic immunoglobulins. The polytypic nature of B lymphocytes was demonstrated by immunohistochemistry and polymerase chain reaction. Recognition of unusual marginal zone hyperplasia in reactive lymph node lesions is important to avoid confusion with nodal involvement in various low-grade B cell lymphomas presenting a marginal zone distribution pattern.

Adult↗

PubMed2001

Detection of micrometastasis in sentinel lymph nodes of patients with primary cutaneous melanoma.

The technique of sentinel lymph node (SLN) biopsy has been demonstrated to be highly predictive for the detection of melanoma micrometastases in the regional lymph node basin. Therefore, the SLN was proposed to accurately reflect the lymph node status of patients with primary cutaneous melanoma. As the regional lymph node status is one of the most powerful predictors of survival in patients with primary melanoma, the histopathologic assessment is critically important for accurate staging. In approximately 20% (ranging from 9% to 42%) of patients with primary melanoma, the SLN was found to be tumor-positive by histopathology or immunohistochemistry. However, the true incidence of metastatic melanoma cells in (sentinel) lymph nodes is underestimated by histopathologic examination. Recently, the method of reverse transcription-polymerase chain reaction (RT-PCR) for tyrosinase mRNA has been used as a molecular marker for the presence of melanoma cells. Tyrosinase RT-PCR was demonstrated to significantly increase the detection of melanoma cells in SLNs as compared to histopathology. All lymph nodes positive by histopathology were shown to express tyrosinase by RT-PCR. Furthermore, tyrosinase transcripts were also detected in 36-52% of stage I and II melanoma patients with SLNs negative by histopathology. Importantly, the recurrence rate was significantly higher in patients with histologically negative SLNs who were found to be positive by RT-PCR than in patients with negative results by both techniques. These findings indicate that RT-PCR status of the SLN is more sensitive for detection of minimal melanoma disease than histopathology. Therefore, the RT-PCR status of the SLN may be suitable to improve melanoma staging and may serve as a prognostic factor in patients with primary cutaneous melanoma.

Biomarkers, Tumor↗

PubMed1997

The stiffness of lymph nodes containing lung carcinoma metastases: a new diagnostic parameter measured by a tactile sensor.

BACKGROUND: It is believed that the stiffness or hardness of a lymph node containing a metastasis differs from that of lymph node without a metastasis because of the difference in tissue density, which is derived from the lymph node's histopathologic features. Prior to this study, however, there had been no attempts to quantify the hardness or stiffness of lymph nodes. The authors developed a new tactile sensor and system for measuring the stiffness (g/cm) of lymph nodes accurately, and they studied its utility as a tool for diagnosing lymph node metastases. METHODS: Clinical specimens were obtained from 14 patients who underwent lobectomy or pneumonectomy with hilar and mediastinal lymph node dissection for nonsmall cell lung carcinoma at the University of Tokyo between January and July 1996. With the tactile sensor developed by the authors, 212 resected lymph nodes were measured for their stiffness. RESULTS: Among these 212 resected lymph nodes, 57 were diagnosed as containing metastases (38 from adenocarcinomas and 19 from squamous cell carcinomas). The mean stiffness of the lymph nodes that contained metastases was 3.35 +/- 1.57 g/cm, and that of lymph nodes without metastases was 1.23 +/- 0.50 g/cm (P < 0.001). Receiver operating characteristic analysis revealed that the area under the curve was 0.93, indicating excellent accuracy of the method. When the cutoff was 1.5 g/cm, the sensitivity was 91.2% and the specificity was 78.1% for detection of lymph node metastases. CONCLUSIONS: Measurement of the stiffness of resected lymph nodes was confirmed as an accurate approach to diagnosing lymph node metastases without knowledge of other factors, such as lymph node size or color.

Aged↗

PubMed2001

Human potency predictions for aldehydes using the local lymph node assay.

The murine local lymph node assay (LLNA) assesses skin sensitization potential as a function of proliferative responses induced in lymph nodes draining the site of topical exposure to test chemical. It has been shown that interpolation of LLNA dose-response data to define the concentration of test chemical required to induce a 3-fold stimulation of proliferation (EC3) offers the prospect of a quantitative index of the relative potency of a contact allergen. Initial studies have demonstrated that there exists a strong (inverse) correlation between EC3 values and contact allergenic potency in humans. Thus, materials with a low EC3 value were more potent contact allergens in humans. However, it is necessary to examine a wide range of allergens to demonstrate that such correlations are generally true. Thus, in the present study, 10 aldehydes of varying degrees of allergenicity in man were evaluated in the LLNA and their EC3 values derived. Formaldehyde was regarded as the strongest allergen in man and also had the lowest EC3 value, 0.35% (equivalent to 0.93% formalin). In contrast, the extremely weak allergen vanillin and the non-sensitizer ethyl vanillin both had EC3 values of >50%. For the remaining 7 aldehydes, there was a close similarity between what is judged to be their rank order of allergenicity in humans and EC3 values derived from analysis of LLNA data. These results support further the utility of EC3 determinations in the LLNA as a measure of the relative potency of a contact allergen.

Aldehydes↗

PubMed1991

[DNA ploidy in submucosal cancer of the stomach and its relationship to lymph node metastasis].

The relationship between DNA ploidy and lymph node metastasis was determined in 40 cases of gastric cancer confined to the submucosa (with lymph node metastasis 20 cases and without 20 cases). The DNA ploidy patterns were classified as follows: Type D, Type A1 and Type A2. Of the 20 cases with lymph node metastasis, 1 was Type D, 7 were Type A1 and 12 were Type A2. The likelihood of lymph node metastasis was 12.5% (1/8) for Type D, 43.8% (7/16) for Type A1 and 75.0% (12/16) for Type A2. It is concluded that although gastric cancer confined to the submucosa is classified as early one, analysis of DNA content places such tumors with lymph node metastasis into the advanced cancer category.

DNA, Neoplasm↗

PubMed2006

Three-dimensional atlas of lymph node topography based on the visible human data set.

Comprehensive atlases of lymph node topography are necessary tools to provide a detailed description of the lymphatic distribution in relation to other organs and structures. Despite the recent developments of atlases and guidelines focusing on definitions of lymphatic regions, a comprehensive and detailed description of the three-dimensional (3D) nodal distribution is lacking. This article describes a new 3D atlas of lymph node topography based on the digital images of the Visible Human Male Anatomical (VHMA) data set. About 1,200 lymph nodes were localized in the data set and their distribution was compared with data from current cross-sectional lymphatic atlases. The identified nodes were delineated and then labeled with different colors that corresponded to their anatomical locations. A series of 2D illustrations, showing discrete locations, description, and distribution of major lymph nodes, was compiled to form a cross-sectional atlas. The resultant contours of all localized nodes in the VHMA data set were superimposed to develop a volumetric model. A 3D reconstruction was generated for the lymph nodes and surrounding structures. The volumetric lymph node topography was also integrated into the existing VOXEL-MAN digital atlas to obtain an interactive and photo-realistic visualization of the lymph nodes showing their proximity to blood vessels and surrounding organs. The lymph node topography forms part of our whole body atlas database, which includes organs, definitions, and parameters that are related to radiation therapy. The lymph node topography atlas could be utilized for visualization and exploration of the 3D lymphatic distribution to assist in defining the target volume for treatment based on the lymphatic spread surrounding the primary tumor.

Anatomy, Cross-Sectional↗

PubMed2004

[Sentinel lymph node biopsy in breast cancer: state of the art].

Axillary lymph node excision of level I and II with at least 10 lymph nodes is the operative gold standard for invasive breast cancer. Axillary lymph node excision is a diagnostic procedure for histopathologic tumor classification, for assessment of prognosis, local tumor control and adjuvant therapy decision. The sentinel node biopsy is a minimal-invasive procedure to determine the axillary lymph node status by excision of one or more sentinel nodes. This procedure is being increasingly implemented in breast cancer surgery. The classical axillary lymph node excision can be replaced by sentinel node biopsy if sentinel nodes are free of invasion in the intraoperative as well as in the final histopathological report. Sentinel node biopsy can become an operative routine procedure only in a quality-controlled environment.

Breast Neoplasms↗

PubMed2002

Role of ultrasound-guided fine-needle aspiration of indeterminate and suspicious axillary lymph nodes in the initial staging of breast carcinoma.

BACKGROUND: Ultrasound (US) is more sensitive than physical examination alone in determining axillary lymph node involvement during preliminary staging of breast carcinoma. Due to occasional overlap of sonographic features of benign and indeterminate lymph nodes, fine-needle aspiration (FNA) of sonographically indeterminate/suspicious lymph nodes can provide a more definitive diagnosis than US alone. This study was undertaken to determine the diagnostic accuracy of US-guided FNA of indeterminate/suspicious/metastatic-appearing axillary lymph nodes during the initial staging of breast carcinoma. METHODS: The cytology of 103 cases of US-guided FNA of nonpalpable indeterminate/suspicious/metastatic-appearing lymph nodes was compared with the final histopathologic status of the entire axilla after axillary dissection. The final axillary lymph node status was categorized as either negative when all lymph nodes were negative for metastasis or positive when there was evidence of metastasis in one or more lymph nodes. The sensitivity, specificity, diagnostic accuracy, and false-negative rate of US-guided FNA of nonpalpable axillary lymph nodes in the preliminary staging process were calculated. RESULTS: In 51 of 103 cases (49.5%), the US-guided FNA and histopathology were both positive for metastasis. In 24 of 103 cases (23.3%), both were negative. The apparent false-positive FNA in 16 (15.5%) cases was explained by the complete response of the metastatic lymph nodes to neoadjuvant chemotherapy in the interval between FNA and axillary dissection. In 12 cases (11.6%), US-guided FNA was negative, but metastasis was seen in histologic sections. All cases with three or more lymph nodes with metastatic disease and 93% of those with metastatic deposit measuring more than 0.5 mm were detected by US-guided FNA. The probability of detecting lymph nodes with smaller metastatic deposit measuring less than 0.5 cm was 44%. The overall sensitivity of US-guided FNA was 86.4%, the specificity was 100%, the diagnostic accuracy was 79.0%, the positive predictive value was 100%, and the negative predictive value was 67%. CONCLUSIONS: US-guided FNA of nonpalpable indeterminate and suspicious axillary lymph nodes is a simple, minimally invasive, and reliable technique for the initial determination of axillary lymph node status in breast carcinoma. The common causes of discrepancy between the initial and final axillary lymph node status include failure to visualize all lymph nodes during US examination, small-sized metastases, and preoperative neoadjuvant chemotherapy.

Axilla↗

PubMed1995

Deficiency in T cell responses of human fetal lymph node cells: a lack of accessory cells.

Lymph node and spleen cells of human foetuses from the 18th to the 24th week of gestation were analysed with regard to their phenotypes and their functional capacities. Fetal mesenteric lymph nodes contain high percentages of CD45RA+ T cells and few B cells and monocytes, whereas the fetal spleen is comprised of equal numbers of T and B cells as well as monocytes/macrophages. Functional analysis of lymph node T cells revealed a lack of proliferative response to PHA or CD3 specific mAb, despite induction of expression of the activation marker CD69. Proliferation of LN cells and thymocytes was observed upon addition of exogenous IL-2. An allogeneic EBV transformed tumour cell line, known to be an effective antigen presenting cell, could induce proliferation of LN cells without exogenous IL-2 and fetal spleen cells could proliferate in response to all stimuli tested without additional IL-2. Splenic non-T cells could restore the proliferation of lymph node cells as efficiently as IL-2 or the EBV transformed B cell line. Separated B cells were more effective than plastic adherent cells on a per cell basis. Naivity of the fetal immune system is therefore not only reflected by the expression of markers representative for naive lymphocytes but can also be due to the absence of potential accessory cells in the different lymphoid organs.

Adult↗

PubMed1984

Morphologic changes in lymph nodes of macaques with an immunodeficiency syndrome.

Lymph nodes from macaque monkeys with an immunodeficiency syndrome were examined by electron microscopy and both routine histologic and immunoperoxidase staining techniques, using monoclonal antibodies that recognize specific primate lymphocyte subsets. In the early stages of disease, marked follicular hyperplasia and a reduced paracortex comprised predominantly of T8-positive (suppressor/cytotoxic) cells were observed. In monkeys with more advanced disease, lymph nodes showed follicular involution and loss of B cells. Vasculature was seen prominently in the paracortex of these nodes; cellular elements included a mixture of small lymphocytes and larger cells, which by ultrastructural criteria appeared to be lymphoblasts. Lymph nodes in terminal stages of this disease showed a total effacement of architecture with a marked depletion of lymphocytes. These findings are remarkably similar to the lymph node changes seen in humans with acquired immune deficiency syndrome and underline the importance of this disease in macaques as a model for studying acquired immunodeficiency states.

Acquired Immunodeficiency Syndrome↗

PubMed1991

[Relation of tumor size, lymph node status and prognosis in breast cancer].

Tumor size and the extent of axillary lymph node involvement are the two most important prognostic factors for breast cancer, but their relation is not clear. Data on 2189 cases of radical surgery from 1956-1985 showed a linear relation between tumor size and percentage of cases with positive lymph node involvement. A negative relation was noted between tumor size, the extent of lymph node involvement and prognosis. There was a significance difference in survival rate between one group, two group or more lymph nodes involve. The worst prognosis was seen in those patients with level 3 lymph nodes involve. Tumor size and lymph node status were found to be independent but additive prognostic indicators. If there was no lymph node involvement, the survival rate was decreased because of tumor size. In cases of 1-3 and 4-6 lymph nodes involved, the survival rate was not different when tumor size was less than 5 cm, but there was a significant difference when tumor size large than 5 cm. In cases of more than 7 nodes involved, the survival rate decreased regardless of tumor size. Lymph node metastasis was more important than tumor size in prognosis. The relation of different TNM combination with prognosis was investigated, and the importance of the treatment of internal mammary lymph node in breast cancer was emphasized.

Breast Neoplasms↗

PubMed1985

[Quantitative and qualitative analysis on the lymph node metastasis of carcinoma of the esophagus].

The results of quantitative and qualitative analysis of lymph nodes dissected during resection of the esophageal carcinoma are as follows. The rate of positive lymph nodes per number of cases was 51.3% (120/234 patients). The rate of positive lymph nodes per number of nodes examined was 15.9% (406/2548 nodes). The correlation between the n-number and the average number of positive lymph nodes for a patient is shown. In the cases in which tumors disappeared from the adventitia of the esophagus by pre-operative radiation, the rate of positive lymph nodes per number of cases and of nodes examined were less than other cases. The metastases in the distant lymph nodes were much less. In the cases in which tumors reached the surgical margin on the adventitia side of the esophagus, the rate of positive lymph nodes per number of cases and of nodes examined were more than others. The metastases in the distant lymph nodes were much more. The pre-operative radiation had no influence on the spreading of the lymph node metastasis. The n-number, the number of positive lymph nodes and of dissected nodes, and the rate of them for each patient had great influence on long-term results.

Adult↗

PubMed2003

[Prognostic significance of lymph node micrometastasis in colorectal cancer].

BACKGROUND & OBJECTIVE: There have been many controversies about the prognostic significance of lymph node micrometastasis. The aim of this study was to characterize the prognostic significance of lymph node micrometastasis of colorectal cancer. METHODS: Specimens of curative resection between 1988 and 2001 were collected from The Affiliated Hospital of Jianghan University Medical and Life Science College. All 80 patients (30 cases of rectal cancer, 50 cases of colon cancer) had complete examination data. A total of 3869 lymph nodes (48.36 per case) were found by clearing fat method. The interrupted serial 4-micron sections, routine hematoxylin and eosin staining and immunohistochemistry methods were used to detect the lymph node metastasis and micrometastasis (small tumor cells cluster diameter <or=0.2 mm or tumor cells detected in the lymph nodes <or=50). All data was processed using Cox univariate analysis and Spearman rank correlation analysis (SAS 8.1 software). RESULTS: Metastases were found in 232 (6%) lymph nodes examined and micrometastases in 39 (1.01%) lymph nodes. In the cases of rectal cancer, a highly significant correlation was found between lymph node metastases and mortality by univariate analysis (Chi(2)=9.94, P=0.0016) and micrometastases by Spearman rank correlation analysis (r=0.44, P=0.016). In the cases of colon cancer, a highly significant correlation was found among lymph node metastases (Chi(2)=9.52, P=0.002), UICC lymph node staging (Chi(2)=5.73, P=0.0167) and mortality by univariate analysis. And Spearman rank correlation analysis demonstrated a significant correlation between lymph node micrometastasis and Dukes' lymph node staging (r=0.314, P=0.008). CONCLUSION: Lymph node micrometastasis possesses considerable value for prognosis of colorectal cancer, but should be used in integration with other indicators.

Adult↗

PubMed2004

What factors affect lymph node yield in surgery for rectal cancer?

OBJECTIVE: The detection of lymph node metastases is of vital importance in patients undergoing excisional surgery for rectal cancer as it provides important prognostic information and facilitates decision-making with regards to adjuvant therapy. It has been suggested that patients in whom only a small number of nodes are present in the excised specimen have a worse prognosis, presumably due to inadequate lymphadenectomy and consequent understaging of the disease. The aim of this study was to determine which factors affect the yield of lymph nodes. METHODS: This was a retrospective study of patients who had undergone a resection for histologically proven adenocarcinoma of the rectum. The total number of lymph nodes identified in the excised specimen was recorded in each case. A multivariate analysis was performed to ascertain whether this number was significantly influenced by any of several variables. RESULTS: A total of 167 patients were studied (M:F ratio 107 : 60, median age 70 years). The median number of lymph nodes contained within the resected specimen was 16 (interquartile range 10-21). On univariate analysis a significantly higher yield of lymph nodes was obtained with tumours in the middle third of the rectum (P=0.007), larger tumours (P < 0.001), more locally advanced tumours according to both pT staging (P=0.001) and Dukes' staging (P=0.020), an increased number of involved nodes (P=0.003) and examination by a specialist histopathologist (P=0.003). On multivariate analysis the only significant variables were tumour size (P=0.021), number of positive nodes (P=0.007) and histopathologist (P=0.021). CONCLUSIONS: The number of lymph nodes identified within the excised specimen in patients undergoing resection of a rectal cancer positively correlates with the size of the tumour and is also dependent on the examining histopathologist. In addition, in node-positive patients the number of involved nodes increases with increasing lymph node yield.

Adenocarcinoma↗

PubMed2006

[Lymph node metastasis of patients with intrahepatic cholangiocarcinoma].

OBJECTIVE: To investigate the relationship between lymph node metastasis and prognosis in patients of intrahepatic cholangiocarcinoma (ICC). METHODS: A retrospective clinical analysis was made in 132 cases of ICC, who admitted to our hospital from December 1996 to June 2003. Kaplan-meier method was used to calculate their survival rates, chi(2) test to compare the difference of sample rates. Logistic regression analysis was performed to determine the factors influencing lymph node metastasis and log-rank univariate analysis was used to assess the role of lymph node metastasis in the long-survival. RESULTS: Lymph node metastasis in hepatoduodenal ligament could be detected in all 29 preoperative and 48 postoperative lymph metastatic cases, without "jumping-metastasis". Lymph metastasis was one of the major causes of postoperative mortality, and resulted in 36 of 58 followed-up death postoperatively. According to logistic analysis, pathological types of the carcinoma (chi(2) = 4.071, P = 0.044) and periductal-infiltrating tumors (chi(2) = 3.872, P = 0.037) were significant predictors of lymph node metastasis. In all 98 radical resections, 46 cases performed skeletonization of the hepatoduodenal ligament while other 52 cases not. The median survival of the two groups was 20 months and 13 months respectively (chi(2) = 9.82, P < 0.01). CONCLUSIONS: Lymph nodes in the hepatoduodenal ligament may be sentinel nodes for ICC lymph node metastasis. Aggressive treatment of lymph node metastasis in the hepatoduodenal ligament is an important strategy to improve the long-survival of postoperative ICC patients.

Adult↗

PubMedDate not supplied

Sentinel lymph node mapping in colorectal cancer: a feasibility study.

AIMS AND BACKGROUND: Sentinel lymph node (SLN) biopsy is currently used and investigated in melanoma and in breast cancer. Its utility in gastrointestinal malignancies is still under debate. The prognosis of colorectal cancer patients is strongly related to the lymphatic involvement. The aim of this study was to evaluate the feasibility of SLN mapping in colorectal cancer and to assess its impact on pathological staging and treatment. METHODS AND STUDY DESIGN: We injected blue dye in 11 colorectal cancer patients during surgery. After resection the tumor specimen was examined to identify blue-stained lymph nodes and these lymph nodes were sent separately to the pathologist. Routine hematoxylin-eosin examination was performed on all nodes (including blue ones). No other techniques (eg immunohistochemistry or PCR) were performed. RESULTS: Sentinel lymph nodes were successfully identified in 10 of the 11 patients. We observed only one false negative result (10%) and the agreement between SLN and other lymph node status was 80% (8/10). One patient was upstaged: SLN was positive for metastases while the other lymph nodes were negative. CONCLUSIONS: Lymphatic mapping using patent blue dye is feasible in colorectal cancer. The identification of lymph nodal metastases by this technique led to upstaging of one patient, who may benefit from adjuvant therapy. These initial results prompt further investigation of this procedure as an accurate, minimally invasive staging approach in early colorectal cancer. We proceed with our study to evaluate the role of SLN mapping in colorectal cancer management.

Aged↗

PubMed2004

Radioisotope lymph node mapping in nonsmall cell lung cancer: can it be applicable for sentinel node biopsy?

BACKGROUND: Previous studies on intrathoracic lymph node mapping have focused on the validity of a sentinel node concept, but not on the usefulness for sentinel node biopsy. METHODS: The subjects were 15 patients clinically diagnosed with N0 nonsmall cell lung cancer. Technetium-99m tin colloid was injected into the peritumoral area 1 day preoperatively and a time course of tracer migration was monitored by scintigraphy. A hand-held gamma probe counter was used to count the intrathoracic lymph node stations. Resected nodes were also counted to assess the accuracy of the intrathoracic counting. RESULTS: Serial scintigraphies showed that the tracer migrated through airways and the appearance resembled hot nodes. On intrathoracic counting, 50% of the nodal stations appeared positive; however, only 23% of these apparently positive nodal stations were ultimately shown to be truly radioactive. The true positive and true negative rates of detecting intrathoracic hot nodes were 100% and 56%, respectively. Because the counts of the nodal stations could include the counts from the hot primary tumor ("shine-through") or airway radioactivity, legitimate hot nodes were identified after dissecting all the apparently positive nodal stations. Two of the 9 patients in whom hot nodes were identified had nodal metastatic disease and actually had tumor cells within the hot nodes. The only complication related to the preoperative injection of technetium-99m was a minor pneumothorax. CONCLUSIONS: Although radioisotope intrathoracic lymph node mapping is safe, it appears to be unsuitable for sentinel node biopsy because shine-through and the airway-migrated radioactive tracer complicated the intrathoracic counting. Only serial scintigraphy could distinguish hot nodes from airway migration.

Aged↗