David Wiese

Molecular Staging of Early Colon Cancer on the Basis of Sentinel Node Analysis: A Multicenter Phase II Trial

PURPOSE Approximately 30% of patients with American Joint Committee on Cancer stage I or II colorectal cancer (CRC) develop systemic disease. We hypothesized that multimarker reverse transcriptase-polymerase chain reaction (RT-PCR) analysis of sentinel lymph nodes (SNs) draining a primary CRC could detect micrometastases not detected by conventional histopathologic analysis. PATIENTS AND METHODS In a multi-institutional study, 40 patients with primary CRC underwent dye-directed lymphatic mapping at the time of colon resection. Each dye-stained SN was tagged, and the tumor and regional nodes were resected en bloc. All lymph nodes were examined by conventional hematoxylin and eosin (HE) staining. In addition, each SN was cut into multiple sections for cytokeratin immunohistochemical (CK-IHC) staining and for RT-PCR and electrochemiluminescent detection of three markers: beta-chain human chorionic gonadotropin, hepatocyte growth factor receptor, and universal melanoma-associated antigen. Whenever possible, RT-PCR assay was also performed on primary tumor tissue. The detection sensitivity of individual markers was 10(-3) to 10(-4) microg of RNA and one to five tumor cells in 10(7) lymphocytes of healthy donors. RESULTS One to three SNs were identified in each patient. An average of 15 nodes were removed from each CRC specimen. No nonsentinel (untagged) node contained evidence of tumor if all tagged (sentinel) nodes in the same specimen were histopathology tumor-negative. HE staining of SNs identified tumor in 10 patients (25%), and CK-IHC of SNs identified occult micrometastases in four patients (10%) whose SNs were negative by HE. Of the remaining 26 patients with no evidence of SN involvement by HE or CK-IHC, 12 (46%) had positive RT-PCR results. The number of markers expressed in each SN correlated (P <.04) with the T stage of the primary tumor. There was 79% concordance in marker expression for the respective pairs (n = 38) of primary tumor and histopathologically positive SNs, and 86% (12 of 14) concordance between RT-PCR positive and histopathologically positive SNs. CONCLUSION Identification and focused examination of the SN is a novel method of staging CRC. CK-IHC and RT-PCR identified occult micrometastases in 53% of patients whose SNs were negative by conventional staging techniques. These ultrasensitive assays of the SN can identify patients who may be at high risk for recurrence of CRC and therefore are more likely to benefit from systemic adjuvant therapy.

Prognostic impact of micrometastases in colon cancer: interim results of a prospective multicenter trial.

Objective:The 25% rate of recurrence after complete resection of stage II colon cancer (CC) suggests the presence of occult nodal metastases not identified by hematoxylin and eosin staining (H&E). Interim data from our ongoing prospective multicenter trial of sentinel node (SN) biopsy indicate a 29.6% rate of micrometastases (MM) identified by immunohistochemical staining (IHC) of H&E-negative SNs in CC. We hypothesized that these MM have prognostic importance. Methods:Between March 2001 and August 2006, 152 patients with resectable colorectal cancer were enrolled in the trial. IHC and quantitative RT-PCR (qRT) assay were performed on H&E-negative SNs. Results were correlated with disease-free survival. Results:The sensitivity of lymphatic mapping was significantly better in CC (75%) than rectal cancer (36%), P < 0.05. Of 92 node-negative CC patients 7 (8%) were upstaged to N1 and 18 (22%) had IHC MM. Four patients negative by H&E and IHC were positive by qRT. At a mean follow-up of 25 months, 15 patients had died from noncancer-related causes, 12 had developed recurrence, 5 had died of CC (2 with macrometastases, 3 with MM), and 7 were alive with disease. The 12 recurrences included 4 patients with SN macrometastases and 6 with SN MM (2 by IHC, 4 by qRT). One of the 2 SN-negative recurrences had other positive lymph nodes by H&E. All patients with CC recurrences had a positive SN by either H&E/IHC or qRT. No CC patient with a negative SN by H&E and qRT has recurred (P = 0.002). Conclusion:This is the first prospective evaluation of the prognostic impact of MM in colorectal cancer. These results indicate that the detection of MM may be clinically relevant in CC and may improve the selection of patients for adjuvant systemic chemotherapy. Patients with CC who are node negative by cumulative detection methods (H&E/IHC and qRT) are likely to be cured by surgery alone.

Prognostic Relevance of Occult Nodal Micrometastases and Circulating Tumor Cells in Colorectal Cancer in a Prospective Multicenter Trial

Purpose: Nodal micrometastasis and circulating tumor cells detected by multimarker quantitative real-time reverse transcription-PCR (qRT-PCR) may have prognostic importance in patients with colorectal cancer. Experimental Design: Paraffin-embedded sentinel lymph nodes from 67 patients and blood from 34 of these patients were evaluated in a prospective multicenter trial of sentinel lymph node mapping in colorectal cancer. Sentinel lymph nodes were examined by H&E staining and cytokeratin immunohistochemistry. Sentinel lymph nodes and blood were examined by a four-marker qRT-PCR assay (c-MET, melanoma antigen gene-A3 family, β1→4-N-acetylgalactosaminyltransferase, and cytokeratin-20); qRT-PCR results were correlated with disease stage and outcome. Results: In H&E-negative sentinel lymph node patients that recurred, cytokeratin immunohistochemistry and qRT-PCR detected metastasis in 30% and 60% of patients, respectively. Disease-free survival differed significantly by multimarker qRT-PCR upstaged sentinel lymph node (P = 0.014). qRT-PCR analysis of blood for circulating tumor cells correlated with overall survival (P = 0.040). Conclusion: Molecular assessment for micrometastasis in sentinel lymph node and blood specimens may help identify patients at high risk for recurrent colorectal cancer, who could benefit from adjuvant therapy.

Pathologic evaluation of sentinel lymph nodes in colorectal carcinoma

BACKGROUND The identification of lymph node metastases in colorectal resection specimens is necessary for accurate tumor staging. However, routine lymph node dissection by the pathologist yields only a subset of nodes removed surgically and may not include those nodes most directly in the path of lymphatic drainage from the tumor. Intraoperative mapping of such sentinel lymph nodes (SLNs) has been reported in cases of melanoma and breast cancer. We applied a similar method to cases of colorectal carcinoma, with emphasis on the pathology of the SLNs. METHODS Eighty-three consecutive patients with colorectal carcinoma were evaluated after intraoperative injection of 1 to 2 mL of 1% isosulfan blue dye (Lymphazurin) into the peritumoral subserosa. Blue-stained lymph nodes were suture-tagged by the surgeon within minutes of the injection for identification by the pathologist, and a standard resection was performed. Designated SLNs were sectioned at 10 levels through the block; a cytokeratin immunostain (AE1) was also obtained. To evaluate the possibility that increased detection of metastases in the SLN might be solely due to increased histologic sampling, all initially negative non-SLNs in the first 25 cases were sectioned also at 10 levels. RESULTS Sentinel lymph nodes were identified intraoperatively in 82 (99%) of 83 patients and accounted for 152 (11.9%) of 1275 lymph nodes recovered, with an average of 1.9 SLNs per patient. A total of 99 positive lymph nodes (38 positive SLNs and 61 positive non-SLNs) were identified in 34 node-positive patients. The SLNs were the only site of metastasis in 17 patients (50%), while 14 patients (41%) had both positive SLNs and non-SLNs. Three patients (9%) had positive non-SLNs with negative SLNs, representing skip metastases. In patients with positive SLNs, 91 (19%) of 474 total lymph nodes and 53 (12%) of 436 non-SLNs were positive for metastasis. In patients with negative SLNs, 8 (1%) of 801 total lymph nodes and 8 (1.2%) of 687 non-SLNs were positive for metastasis. Multilevel sections of 330 initially negative non-SLNs in the first 25 patients yielded only 2 additional positive nodes (0. 6%). All patients with positive SLNs were correctly staged by a combination of 4 representative levels through the SLN(s) together with a single cytokeratin immunostain. CONCLUSIONS Intraoperative mapping of SLNs in colorectal carcinoma identifies lymph nodes likely to contain metastases. Focused pathologic evaluation of the 1 to 4 SLNs so identified can improve the accuracy of pathologic staging.

Intraperitoneal Virtual Biopsy by Fibered Optical Coherence Tomography (OCT) at Natural Orifice Transluminal Endoscopic Surgery (NOTES)

IntroductionFibered optical coherence tomography (OCT) in conjunction with natural orifice transluminal endoscopic surgery (NOTES) could provide a facility for rapid, in situ pathological diagnosis of intraperitoneal tissues in a truly minimally invasive fashion.Materials and MethodsA large porcine model was established to test this hypothesis. A standard double channel gastroscope (Olympus) was used to achieve a transgastric access to the peritoneum and initiate the pneumoperitoneum. Magnetic retraction was used to display the sigmoid colon along with its mesentery. A commercially available fibered OCT probe (NIRIS system, Imalux) was inserted via a working channel of the gastroscope and used to assess intraperitoneal tissues. Separately, OCT images of human tissue specimens ex vivo were contrasted with representative standard histopathological slides.ResultsIntraperitoneal OCT provided clear real-time images of both the serosal and muscularis propria mural layers as well as the submuscosal–muscularis interface. Examination of mesenteric lymph nodes (including sentinel nodes) allowed visualization of their subcapsular sinus. Comparison of representative cross-sections however failed to evince sufficient resolution for confident diagnosis.ConclusionThis approach is technically feasible and, if the technology is advanced and proven accurate in human patients, could potentially be used to individualize operative extent prior to definitive resection.

Sentinel Lymph Node Mapping in Colon and Rectal Cancer

Sentinel lymph node (SLN) mapping has been widely applied in the staging of solid neoplasms including colon and rectal cancer. Since the first reported feasibility study in 1997, there have been numerous publications validating SLN mapping as a highly accurate and powerful upstaging technique for colon and rectal cancer. In addition to refining the technical aspects of this procedure, these studies have investigated the use of other tracers and operative techniques, while determining the indications, limitations, and pitfalls of SLN mapping in patients with colorectal cancers. This chapter reviews the rationale for performing SLN mapping for the accurate staging of colon and rectal cancers, and provides a brief review of the historical background of the development of the procedure. Landmark publications, which have contributed to the current status of the technique, are discussed. We will focus on the technical details of the procedure, and on the pathological evaluation of the specimen and the SLNs. The various tracers and techniques of SLN mapping in colon and rectal cancer will be discussed. We have performed SLN mapping in more than 240 consecutive patients over the past 7 years. The success rates for identifying at least one SLN for colon and rectal cancer were 100% and 90.6%, respectively. The accuracy rates were 95.8% and 100%, respectively. In terms of upstaging, 32.3% of colon cancer patients with nodal metastases and 16.7% of rectal patients with nodal metastases were upstaged by the detection of micrometastases found in the SLNs only. Finally, we will also discuss the current role as well as the future research directions for SLN mapping in colon and rectal cancer.

Unusual Presentation of Large-Cell Poorly Differentiated Neuroendocrine Carcinoma of the Epiglottis

A 57-year-old postmenopausal white female with a 50-pack-year smoking history presented with intermittent episodes of generalized body aches, headaches, and increasing fatigue over a 4-month period. Her past medical history included hypertension, coronary artery bypass grafting, and hypothyroidism. Her mother had been diagnosed with a rare variety of multiple myeloma. Six months before this presentation, the patient was diagnosed with invasive, poorly differentiated carcinoma of the epiglottis. At that time, neck lymph nodes were not clinically involved and the staging work-up was negative for metastatic disease. She underwent surgical resection of the 1.5-cm carcinoma with clear margins; no elective neck dissection was performed. Because of the poorly differentiated nature of the carcinoma, the patient was offered adjuvant radiation therapy, but she declined it. Two months later, she noticed increasing fatigue and generalized body aches. At that time, her primary care physician noted anterior cervical lymphadenopathy and thyromegaly. Excisional biopsy of a right

Sentinel Lymph Node Mapping in Colorectal Cancer

Sentinel lymph node (SLN) mapping has been widely applied in the staging of solid neoplasms including colon and rectal cancer. Since the first reported feasibility study in 1997, there have been numerous publications validating SLN mapping as a highly accurate and powerful upstaging technique for colon and rectal cancer. In addition to refining the technical aspects of this procedure, these studies have investigated the use of other tracers and operative techniques, while determining the indications, limitations, and pitfalls of SLN mapping in patients with colorectal cancers.

The prognostic value of additional malignant lesions detected by magnetic resonance imaging versus mammography.

BACKGROUND Nodal positivity is correlated with a poorer prognosis in breast cancer. A study was composed to compare nodal positivity in patients with single versus multiple lesions found on magnetic resonance imaging (MRI) and mammogram (MMG). METHODS A retrospective study of breast cancer patients undergoing MRI and MMG was performed. Nodal positivity was compared in patients with additional invasive lesions found on MRI versus single invasive lesions found on MRI and MMG. RESULTS A total of 425 patients were included. The overall nodal positivity was 23.8%. Patients with single versus multiple malignant lesions had nodal positivity of 20.9% vs 31.1% (P = .04). MRI detected multiple lesions in 120 patients, 80 of which were not detected by MMG (18.8%). Comparing single lesions with additional malignant lesions detected by MRI only, nodal positivity increased from 20.9% to 51.6% (P = .0002). CONCLUSIONS Patients with additional invasive lesions on MRI had significantly higher nodal positivity than single invasive lesions. Hence, addition of MRI in early-stage breast cancer may have prognostic value because of detection of potential node-positive patients.