Rick Cote

PURPOSE: To evaluate our long-term experience with patients treated uniformly with radical cystectomy and pelvic lymph node dissection for invasive bladder cancer and to describe the association of the primary bladder tumor stage and regional lymph node status with clinical outcomes. PATIENTS AND METHODS: All patients undergoing radical cystectomy with bilateral pelvic iliac lymphadenectomy, with the intent to cure, for transitional-cell carcinoma of the bladder between July 1971 and December 1997, with or without adjuvant radiation or chemotherapy, were evaluated. The clinical course, pathologic characteristics, and long-term clinical outcomes were evaluated in this group of patients. RESULTS: A total of 1,054 patients (843 men [80%] and 211 women) with a median age of 66 years (range, 22 to 93 years) were uniformly treated. Median follow-up was 10.2 years (range, 0 to 28 years). There were 27 (2.5%) perioperative deaths, with a total of 292 (28%) early complications. Overall recurrence-free survival at 5 and 10 years for the entire cohort was 68% and 66%, respectively. The 5- and 10-year recurrence-free survival for patients with organ-confined, lymph node-negative tumors was 92% and 86% for P0 disease, 91% and 89% for Pis, 79% and 74% for Pa, and 83% and 78% for P1 tumors, respectively. Patients with muscle invasive (P2 and P3a), lymph node-negative tumors had 89% and 87% and 78% and 76% 5- and 10-year recurrence-free survival, respectively. Patients with nonorgan-confined (P3b, P4), lymph node-negative tumors demonstrated a significantly higher probability of recurrence compared with those with organ-confined bladder cancers (P <.001). The 5- and 10-year recurrence-free survival for P3b tumors was 62% and 61%, and for P4 tumors was 50% and 45%, respectively. A total of 246 patients (24%) had lymph node tumor involvement. The 5- and 10-year recurrence-free survival for these patients was 35%, and 34%, respectively, which was significantly lower than for patients without lymph node involvement (P <.001). Patients could also be stratified by the number of lymph nodes involved and by the extent of the primary bladder tumor (p stage). Patients with fewer than five positive lymph nodes, and whose p stage was organ-confined had significantly improved survival rates. Bladder cancer recurred in 311 patients (30%). The median time to recurrence among those patients in whom the cancer recurred was 12 months (range, 0.04 to 11.1 years). In 234 patients (22%) there was a distant recurrence, and in 77 patients (7%) there was a local (pelvic) recurrence. CONCLUSION: These data from a large group of patients support the aggressive surgical management of invasive bladder cancer. Excellent long-term survival can be achieved with a low incidence of pelvic recurrence.

Noninvasive transitional cell carcinomas of the bladder can have two distinct morphologies suggesting they contain different genetic alterations. Papillary transitional cell carcinomas (T(a) tumors) are often multifocal and only occasionally progress, whereas flat tumors (carcinomas in situ, CIS), frequently progress to invasive disease. We examined 216 bladder tumors of various stages and histopathologies for two genetic alterations previously described to be of importance in bladder tumorigenesis. Loss of heterozygosity of chromosome 9 was observed in 24 of 70 (34%) T(a) tumors but was present in only 3 of 24 (12%) CIS and dysplasia lesions (P = 0.04). In contrast, only 1 of 36 (3%) T(a) tumors contained a p53 gene mutation compared to 15 of 23 (65%) CIS and dysplasias (P < 0.001), a frequency comparable to that observed in muscle invasive tumors (25 of 49; 51%). The presence of p53 mutations in CIS and dysplasia could explain their propensities to progress since these mutations are known to destabilize the genome. Analysis of several tumor pairs involving a CIS and an invasive cancer provided evidence that the chromosome 9 alteration may in some cases be involved in the progression of CIS to more invasive tumors, in addition to its role in the initiation of T(a) tumors. However, the CIS and secondary tumor were found to contain different genetic alterations in some patients suggesting divergent progression pathways. Bladder carcinogenesis may therefore proceed through two distinct genetic alteration pathways responsible for generating superficial tumors with differing morphologies and pathologies.

Generation of nanomechanical cantilever motion from biomolecular interactions can have wide applications, ranging from high-throughput biomolecular detection to bioactuation. Although it has been suggested that such motion is caused by changes in surface stress of a cantilever beam, the origin of the surface-stress change has so far not been elucidated. By using DNA hybridization experiments, we show that the origin of motion lies in the interplay between changes in configurational entropy and intermolecular energetics induced by specific biomolecular interactions. By controlling entropy change during DNA hybridization, the direction of cantilever motion can be manipulated. These thermodynamic principles were also used to explain the origin of motion generated from protein-ligand binding.

PURPOSE: This study was performed to evaluate the potential of specific mRNA markers to detect micrometastases by reverse-transcriptase polymerase chain reaction (RT-PCR) and Southern blot analysis of sentinel lymph nodes (SNs) and blood from patients with breast cancer. PATIENTS AND METHODS: We assessed the specificity of carcinoembryonic antigen (CEA), cytokeratin-19 (CK-19), CK-20, gastrointestinal tumor-associated antigen-733.2 (GA733.2), and mucin-1 (MUC-1) in the blood of healthy donors (n = 13) and lymph nodes from patients without cancer (n = 3) by RT-PCR assay. The sensitivity of the RT-PCR assay for the target mRNA markers was assessed in breast cancer cell lines (n = 4), primary breast tumors (n = 8), and the frozen sections of SNs (n = 22) from 22 patients with American Joint Committee on Cancer (AJCC) stages I to IIIA breast cancer. RESULTS: CK-20 was the only mRNA marker not detected in lymph nodes or blood from patients without cancer. Both the blood and lymph nodes from patients without cancer expressed CEA, CK-19, GA733.2, and MUC-1 mRNA. All four breast cancer cell lines and six of eight primary breast tumors expressed all five mRNA markers. Expression of mRNA by the RT-PCR assay in the frozen-section SNs (n = 12) without metastases by conventional histopathology ranged from 8% (CK-20) to 92% (GA733.2). Detection of RT-PCR cDNA products in frozen-section SNs was increased with Southern blot analysis compared with ethidium bromide gel electrophoresis (EtBr) for all mRNA markers except CK-19. CONCLUSION: CEA, CK-19, GA733.2, and MUC-1 show no diagnostic value as mRNA markers for the detection of micrometastases by the RT-PCR assay because they are expressed in the blood and lymph nodes of patients without cancer. Further studies are needed to assess the sensitivity of CK-20 to detect micrometastases by the RT-PCR assay in the blood and frozen-section SNs of patients with breast cancer.

Characterization of single-nucleotide polymorphisms is a major focus of current genomics research. We demonstrate the discrimination of DNA mismatches using an elegantly simple microcantilever-based optical deflection assay, without the need for external labeling. Gold-coated silicon AFM cantilevers were functionalized with thiolated 20- or 25-mer probe DNA oligonucleotides and exposed to target oligonucleotides of varying sequence in static and flow conditions. Hybridization of 10-mer complementary target oligonucleotides resulted in net positive deflection, while hybridization with targets containing one or two internal mismatches resulted in net negative deflection. Mismatched targets produced a stable and measurable signal when only a four-base pair stretch was complementary to the probe sequence. This technique is readily adaptable to a high-throughput array format and provides a distinct positive/negative signal for easy interpretation of oligonucleotide hybridization.