Paul L. Baron

Quantitative real-time RT-PCR detection of breast cancer micrometastasis using a multigene marker panel

Real‐time RT‐PCR is a relatively new technology that uses an online fluorescence detection system to determine gene expression levels. It has the potential to significantly improve detection of breast cancer metastasis by virtue of its exquisite sensitivity, high throughput capacity and quantitative readout system. To assess the utility of this technology in breast cancer staging, we determined the relative expression levels of 12 cancer‐associated genes (mam, PIP, mamB, CEA, CK19, VEGF, erbB2, muc1, c‐myc, p97, vim and Ki67) in 51 negative‐control normal lymph nodes and in 17 histopathology‐positive ALNs. We then performed a receiver operating characteristic (ROC) curve analysis to determine the sensitivity and specificity levels of each gene. Areas under the ROC curve indicated that the most accurate diagnostic markers were mam (99.6%), PIP (93.3%), CK19 (91.0%), mamB (87.9%), muc1 (81.5%) and CEA (79.4.0%). mam was overexpressed in 16 of 17 lymph nodes known to contain metastatic breast cancer at levels ranging from 22‐ to 2.8 × 105‐fold above normal mean expression, whereas PIP was overexpressed from 30‐ to 2.2 × 106‐fold above normal in 13 lymph nodes. Real‐time RT‐PCR analysis of pathology‐negative LN from breast cancer patients revealed evidence of overexpression of PIP (6 nodes), mam (3 nodes) and CEA (1 node) in 8 of 21 nodes (38%). Our results provide evidence that mam, PIP, CK19, mamB, muc1 and CEA can be applied as a panel for detection of metastatic and occult micrometastatic disease.

Immediate vs. salvage resection after local treatment for early rectal cancer

PURPOSE: There is an increasing awareness of local procedures to treat early stage rectal cancer. Abdominoperineal resection (APR) or low anterior resection (LAR) has been recommended if adverse pathologic findings are encountered in the local excision specimen. No data compare the impact on survival of “immediate” resection for adverse featuresvs. “salvage” resection for clinical recurrence. METHODS: We reviewed retrospectively 155 patients who underwent initial curative treatment of invasive rectal cancer by excision (91), snare-cautery (44), and fulguration (20). RESULTS: Twenty-one patients underwent APR/LAR immediately after initial local treatment, whereas another 21 patients underwent salvage APR/LAR for local recurrence. The disease-free survival after APR/LAR was 94.1 percent for the immediate group and 55.5 percent for the delayed group (P<0.05). CONCLUSION: This decreased survival observed after delayed resection supports the recommendation for immediate APR/LAR when adverse pathologic features are present in the excision specimen.

A pilot study evaluating the efficacy of a fully acetylated poly-N-acetyl glucosamine membrane formulation as a topical hemostatic agent ☆ ☆☆

BACKGROUND Topical hemostatic agents are frequently needed for control of intraoperative bleeding. Currently available topical products each have potential drawbacks, making a more effective topical hemostatic agent desirable. This study was performed to evaluate the effectiveness of a particular formulation of a newly available polysaccharide polymer, poly-N-acetyl glucosamine (p-GlcNAc), as a topical hemostatic agent for use in the operating room. Swine splenic incision and splenic capsular stripping hemorrhage models were initially used, with a subsequent pilot human study then performed. METHODS For the swine splenic incision model, anesthetized immature female Yorkshire white swine had a 3 x 8 mm incision created on the spleen. One of 3 agents (p-GlcNAc membrane, oxidized cellulose, or absorbable collagen) was sequentially applied to individual wounds and digitally compressed for 20 seconds. The wound was observed without pressure for 2 minutes. Up to 8 wounds per animal were created in 7 animals. For the swine splenic capsular stripping model a 2 x 2 cm area of capsular stripping on the surface of the spleen to a depth of 3 mm was created. Either p-GlcNAc membrane or oxidized cellulose was applied and digitally compressed for 60 seconds, followed by observation without pressure for 2 minutes. Six wounds per animal were created in 2 animals. If bleeding persisted in either model, a new cycle of compression was applied. These steps were repeated until hemostasis was achieved. No change in hemodynamics or coagulation factors was observed in either model. Subsequently, 10 consecutive patients undergoing elective small-bowel surgery were enrolled on pilot study. A 5 x 3 x 3 mm cruciate incision was created midway between the mesenteric and antimesenteric borders of the small bowel. Either p-GlcNAc membrane formulation or oxidized cellulose was applied (the sequence alternated per patient) with a 400-mg weight used for even, direct pressure. A second cruciate incision was then created on the contralateral side of the bowel to evaluate the second material. The number of applications required for hemostasis was assessed. Hemodynamics, small-bowel pathologic condition, and hematologic parameters were evaluated. RESULTS The p-GlcNAc membrane required fewer cycles of compression in the swine splenic incision model to achieve hemostasis than either absorbable collagen or oxidized cellulose (1.25 vs 2.58 and 3.41, respectively; P < .01) and caused more effective immediate cessation of bleeding (79% for p-GlcNAc vs 17% for both absorbable collagen and oxidized cellulose). With the more traumatic splenic capsular stripping model, p-GlcNAc required fewer cycles of compression to achieve hemostasis than oxidized cellulose (average, 2.5 versus 6.8 respectively; P < .01) and was able to achieve hemostasis with greater efficacy (50%) in 2 applications than did oxidized cellulose (0%; P < .01). When used in the human pilot study, p-GlcNAc membranes required fewer cycles of compression than oxidized cellulose (2.5 vs 5.4, respectively; P < .002), was able to stop bleeding with greater efficacy in 1 cycle of compression (50% vs 0%, respectively; P < .01), and ultimately accomplished hemostasis in 80% of the cases as opposed to 20%. CONCLUSIONS On the basis of its greater hemostatic efficacy as compared with collagen or oxidized cellulose-based products, p-GlcNAc holds promise as an effective topical hemostatic agent and deserves further evaluation.

Melanoma thickness and histology predict sentinel lymph node status

BACKGROUND It remains unclear which patients with melanoma will benefit most from lymphatic mapping and sentinel lymphadenectomy. The purpose of this study is to determine whether primary melanoma histopathologic features could be applied to predict sentinel node status. METHODS One hundred twelve patients underwent sentinel node biopsy between May 1995 and August 1999. Reported histologic features were assessed for predictive value by univariate and multivariate logistic regression. RESULTS The sentinel node was located successfully in 105 of the 112 patients (94%). Twenty-one of these 105 patients (20%) had sentinel nodes that were positive for metastatic disease. Multivariate analyses revealed that tumor thickness greater than 1.5 mm (P = 0.01), ulceration (P <0.01), and lymphovascular invasion (P = 0.05) predicted the presence of micrometastases. CONCLUSIONS The presence of unfavorable histopathology such as ulceration and lymphovascular invasion may identify a group of patients with thin melanomas who would benefit from sentinel lymphadenectomy.

Detection of occult breast cancer micrometastases in axillary lymph nodes using a multimarker reverse transcriptase-polymerase chain reaction panel ☆

BACKGROUND Axillary lymph node status in breast cancer patients remains the single most important predictor of outcomes. Current methods of histopathologic analysis may be inadequate because 30% of node-negative patients recur. The purpose of this study was to test the hypothesis that a multigene reverse transcriptase-polymerase chain reaction (RT-PCR) panel provides a more sensitive method to detect axillary lymph node metastases than routine pathologic examination. STUDY DESIGN Sixty-one consecutive breast cancer patients were evaluated, with nine normal control patients. Nodes > 1 cm were bisected for histopathologic and RT-PCR analysis. Nodal tissue was homogenized, and total RNA was converted into cDNA with reverse transcriptase. Reverse transcriptase-polymerase chain reaction analysis was performed with primers specific for keratin-19, c-myc, prolactin inducible protein (PIP), and beta-actin using ethidium bromide gel electrophoresis. Reverse transcriptase-polymerase chain reaction positive/ pathology negative axillary lymph nodes were reevaluated using step sectioning and immunohistochemical staining. RESULTS Thirty-seven patients had pathologically negative axillary lymph nodes, of which 15 (40%) were positive by RT-PCR analysis. Two RT-PCR negative results (one probably from tissue processing error and the other secondary to sampling error) among the 24 histologically positive specimens were detected (8%). The number of patients in each pathologic stage was 26 patients in stage I; 18, stage IIA; 7, stage IIB; 7, stage IIIA; 3, stage IIIB; and 0 patients in stage IV. By RT-PCR staging, 8 of 26 patients went from stage I to IIA (30%), and 7 of 18 from stage IIA to IIB (39%). Of the RT-PCR positive individuals who were stage I by pathologic analysis, 100% were found to be c-myc positive, 0% keratin-19 positive, and 0% PIP positive; for stage IIIB patients these markers were 50%, 100%, and 100% respectively. Additionally, an increasing number of positive markers per specimen appeared to correlate with larger primary tumor size (p < 0.01) and decreased predicted 5-year survival (r = 0.950, p < 0.002). CONCLUSIONS Multimarker RT-PCR analysis appears to be a readily available and highly sensitive method for the detection of axillary lymph node micrometastases. Longterm followup of RT-PCR positive patients will be required to determine its clinical relevance. If validated as a predictor of disease recurrence, this method would provide a powerful complement to routine histopathologic analysis of axillary lymph nodes.

Differentiation of benign from malignant pancreatic masses by endoscopic ultrasound

AbstractBackground: It is often difficult to determine whether a mass in the pancreas is benign or malignant. The goal was to evaluate whether endoscopic ultrasound (EUS) can reliably establish whether a mass is benign or malignant. Methods: One hundred five patients with possible pancreatic tumors were referred for EUS. Those who were found to have a lesion suspicious for carcinoma and did not have a known malignancy also underwent EUS-guided FNA. Results: A mass suspicious for cancer was identified in 73 patients, whereas inflammatory changes or a normal pancreas was noted in 32 patients. Four of the latter 32 patients were subsequently found to have cancer. EUS-guided FNA was performed on 47 of the 73 patients with a suspicious mass and was read as cancer in 27 patients, atypia in 10 patients, and benign in 10 patients. All 10 patients with atypia were subsequently confirmed to have cancer, and 6 of the 10 patients with a benign FNA were proved to have a tumor at surgery. EUS could differentiate the lesion as malignant with a sensitivity of 95%, specificity 88%, positive predictive value 95%, and negative predictive value 88%. Conclusions: Radial array EUS is helpful in supporting or refuting a diagnosis of cancer in a patient with a pancreatic mass. Although EUS-guided FNA can confirm the diagnosis, a negative FNA should not preclude exploration when clinically indicated.

Factors influencing choice between mastectomy and lumpectomy for women in the Carolinas

The Carolinas have been documented to have a low rate of breast‐conserving surgery. The purpose of this study was to determine factors that influence womens choice between mastectomy and lumpectomy.

The effect of tamoxifen and cisplatin on the disease-free and overall survival of patients with high risk malignant melanoma

The adjuvant treatment of high-risk malignant melanoma remains problematic. Previously we reported moderate success in the treatment of metastatic disease using tamoxifen, cisplatin, dacarbazine and carmustine. Based upon data that suggested tamoxifen and cisplatin were the active agents in this regimen, we initiated a phase II trial of this combination in the adjuvant setting. We treated 153 patients with 4 cycles of tamoxifen (160 mg day–1, days 1–7) and cisplatin (100 mg m–2, day 2) for 28-day intervals. Patients received an anti-nausea regimen of dexamethasone with ondansetron or granisetron. During the first 2 years of follow-up, patients were evaluated every 2 months with a history, physical exam, laboratory work and computed tomography scans of the chest, abdomen and pelvis every 4 months. Thereafter, patients were evaluated every 3 months and radiographic studies were performed if necessary. Currently, with a median follow-up of 36 months, the disease-free survival (DFS) is 68.4% and overall survival (OS) is 84.5%. Kaplan–Meier analysis predicts a 5-year DFS of 62% with an OS of 79%. Relapses after 20 months have been rare. No effect of gender or number of positive lymph nodes was noted, however, stage of disease prior treatment was a factor. The major toxicity proved to be gastrointestinal in nature with nausea the most prevalent symptom. Minimal renal, haematologic and neurologic toxicity occurred. These preliminary results suggest that there is a positive impact of tamoxifen and cisplatin on both the DFS and OS of high-risk malignant melanoma patients. The 5-year projected DFS and OS compare favourably with those reported for the ECOG 1684 trial and warrant confirmation in a prospective randomized trial.

Magnetic resonance cholangiopancreatography: A novel approach to the evaluation of suspected pancreaticobiliary neoplasms

AbstractBackground: Magnetic resonance cholangiopancreatography (MRCP) is a new noninvasive diagnostic method for pancreaticobiliary (PB) imaging without endoscopy, sedation, or iodinated contrast. The purpose of this study was to evaluate the ability of MRCP to depict pancreatic and biliary ductal anatomy compared to that of endoscopic retrograde cholangiopancreatography (ERCP) and to evaluate the ability of MRCP to accurately diagnose PB neoplasms. Methods: Twenty patients had MRCP, and 17 also had ERCP. All studies were read prospectively by experienced reviewers blinded to other imaging data. Pathologic diagnosis was made in all patients. Results: Bile duct dilatation seen by ERCP in 14 of 17 patients was correctly identified by MRCP in all 14 patients, and normal ducts were correctly identified by MRCP in the other 3 patients. The pancreatic duct was visible on MRCP in the pancreatic head in 17 of 20 patients, the body in 17 of 20 patients, and the tail in 15 of 20 patients. At ERCP, pancreatic duct dilatation was present in 11 cases and was identified by MRCP in 10 of them. Eighteen of 20 patients had malignant PB neoplasms. MRCP indicated PB neoplasm in 19 patients. Seventeen of these 19 patients had histologically confirmed malignant neoplasms pathologically, whereas 2 had benign pathology (both chronic pancreatitis). Among the 17 patients who also had ERCP, MRCP and ERCP correctly agreed on a final diagnosis of malignant neoplasm in 14 cases. In the three cases in which MRCP and ERCP disagreed on a final diagnosis, MRCP was correct in one and incorrect in two. Conclusions: MRCP can accurately and noninvasively delineate PB ductal anatomy and diagnose PB neoplasms comparably to ERCP. MRCP is an interesting new noninvasive method for evaluating patients with suspected PB neoplasms.

Local staging of anal and distal colorectal tumors with the magnetic resonance endoscope

BACKGROUND We prospectively assessed the feasibility and accuracy of endoscopic magnetic resonance (EMR) scanning in the local staging of anal and colorectal cancer as compared to endosonography. METHODS Fifteen patients with biopsy-proven anal (n = 2), rectal (n = 11), and distal colonic (n = 2) cancer underwent endosonography followed by EMR imaging. Scans were acquired using the magnetic resonance receiver coil incorporated into the tip of the non-ferromagnetic endoscope. Blinded to endosonography results, two radiologists interpreted the EMR images using the TNM system. Staging results were compared to endosonography in all patients and to histopathology in the 13 colorectal cases. RESULTS EMR imaging, well tolerated in all patients, correlated with endosonography in 10 of 15 and 12 of 15 cases for T- and N-staging, respectively. In the 13 colorectal patients with available histopathology, accuracy of EMR and of endosonography in T-staging was 77% and 85%, respectively; N-staging accuracy was 62% for both. CONCLUSIONS For anal and distal colorectal neoplasms, EMR imaging is feasible and provides local staging comparable to endosonography.