Biomedical subjects

Samir Taneja

Publications and source records attributed to Samir Taneja.

7 recordsLinked to original sources

PubMed2004

Altered N-myc downstream-regulated gene 1 protein expression in African-American compared with caucasian prostate cancer patients.

PURPOSE: The protein encoded by N-myc downstream-regulated gene 1 (NDRG1) is a recently discovered protein whose transcription is induced by androgens and hypoxia. We hypothesized that NDRG1 expression patterns might reveal a biological basis for the disparity of clinical outcome of prostate cancer patients with different ethnic backgrounds. EXPERIMENTAL DESIGN: Patients who underwent radical prostatectomy between 1990 and 2000 at Veterans Administration Medical Center of New York were examined. We studied 223 cases, including 157 African Americans and 66 Caucasians (T2, n = 144; >/=T3, n = 79; Gleason <7, n = 122; >/=7, n = 101). Three patterns of NDRG1 expression were identified in prostate cancer: (a) intense, predominately membranous staining similar to benign prostatic epithelium; (b) intense, nucleocytoplasmic localization; and (c) low or undetectable expression. We then examined the correlations between patients' clinicopathological parameters and different NDRG1 expression patterns. RESULTS: In this study of patients with equal access to care, African-American ethnic origin was an independent predictor of prostate-specific antigen recurrence (P < 0.05). We also observed a significant correlation between different patterns of NDRG1 expression and ethnic origin. Pattern 2 was less frequent in African Americans (21% versus 38%), whereas the reverse was observed for pattern 3 (60% in African Americans versus 44% in Caucasians; P = 0.03). This association remained significant after controlling for both grade and stage simultaneously (P = 0.02). CONCLUSIONS: Our data suggest that different NDRG1 expression patterns reflect differences in the response of prostatic epithelium to hypoxia and androgens in African-American compared with Caucasian patients. Further studies are needed to determine the contribution of NDRG1 to the disparity in clinical outcome observed between the two groups.

Black or African American↗

PubMed2004

Malignant epithelioid angiosarcoma of the external iliac vein presenting as venous thrombosis.

A case is reported of a 28-year-old female who initially presented with a right iliac deep venous thrombosis of unclear etiology. A stenosis in the iliac vein was seen, but no intrinsic or extrinsic mass was noted on multiple imaging studies. The patient presented 2 years later with right hydronephrosis, and at that time a right pelvic mass was discovered. Resection was performed with concomitant reconstruction of the right iliac arterial system, and pathology revealed a malignant epithelioid angiosarcoma.

Adult↗

PubMed2004

Impact of fusion of indium-111 capromab pendetide volume data sets with those from MRI or CT in patients with recurrent prostate cancer.

OBJECTIVE: Our goal was to evaluate the impact of image fusion on the interpretation of indium-111 Prosta-Scint SPECT scans. MATERIALS AND METHODS: Sixty-seven consecutive patients referred for rising prostate-specific antigen (PSA) levels after initial therapy for primary prostate cancer underwent SPECT 96 hr after infusion of (111)In Prosta-Scint, with simultaneous technetium-99m blood pool imaging. Volume data sets from the SPECT scans were then fused with those from CT and MR images of the pelvis using a 3D landmark-based warping program. The SPECT scans were initially interpreted without benefit of MRI or CT fusion. The fused Prosta-Scint MRI-CT volumes were reevaluated by a nuclear radiologist and an MRI radiologist. Independent reviews before and after fusion were available in these patients. Validation of results after fusion was performed through correlation with PSA changes after radiation therapy. RESULTS: Six patients with sites that could not be evaluated and three without their original Prosta-Scint scanning reports were excluded; thus, 58 patients were studied clinically. Seventy-four of 161 prefusion-positive sites were found to be negative after fusion. These 74 sites subsequently were identified primarily as showing bowel, vessel, or marrow uptake after fusion. In two patients, nodal disease was identified although the review before perfusion indicated none. Twenty-five patients previously thought to have nodal disease appeared to have only local disease after fusion. After local radiation therapy, PSA levels decreased in 12 of 25 patients, increased in five, and were unavailable in eight. CONCLUSION: Although Prosta-Scint SPECT alone can help in the proper management of recurrent prostate cancer, fusion with MRI-CT of the pelvis can improve the specificity of the examination.

Aged↗

PubMed2003

Hand-assisted laparoscopy for large renal specimens: a multi-institutional study.

OBJECTIVES: To present our experience with hand-assisted laparoscopy (HAL) for larger renal specimens. One of the theoretical benefits of HAL is the ability to manage large renal specimens, which we defined as tumors greater than 7 cm, and tumors in obese patients. METHODS: Between March 1998 and October 2000, 106 HAL radical nephrectomies were performed for enhancing renal masses, for which 95 patients had complete preoperative, intraoperative, and postoperative data. Of the 95 patients, 32 underwent HAL for large tumors (7 cm or greater) and 41 had a body mass index of 31 or greater. The demographic and outcome data of these two groups were compared with 63 patients who underwent HAL for tumors less than 7 cm and 54 patients with a body mass index of less than 31. RESULTS: When comparing cohorts by tumor size, the only statistically significant differences were in convalescence and specimen weight. Patients with lesions 7 cm or greater required 21 days to recover compared with 18 days for patients with lesions less than 7 cm. Obese patients had statistically significantly higher American Society of Anesthesiologists classifications, longer operative times (214 versus 176 minutes), and longer convalescences (21 versus 17.5 days) compared with nonobese patients. The estimated blood loss and conversion rate was not different between the groups. Furthermore, no difference was noted between the groups in the incidence of positive margins, local recurrence, or metastatic recurrence at a mean follow-up of 12.2 months. CONCLUSIONS: HAL provides a safe, reproducible, and minimally invasive technique to remove large renal tumors and renal tumors in the obese.

Blood Loss, Surgical↗

PubMed2003

Use of fibrin glue and gelfoam to repair collecting system injuries in a porcine model: implications for the technique of laparoscopic partial nephrectomy.

BACKGROUND AND PURPOSE: One of the challenges of laparoscopic partial nephrectomies is the repair of a collecting system injury. We hypothesized that fibrin glue plus Gelfoam could be sufficient to repair such injuries. MATERIALS AND METHODS: Four pigs (eight kidneys) underwent collecting system injuries of various lengths (3, 5, and 10 mm) (N = 8 each) during partial nephrectomy. Gelfoam soaked in the fibrin glue was applied to seal the collecting system and parenchymal defects. After 1 hour of passive filling, the renal pelvis was distended at supraphysiologic pressure to the point of leakage. Each repair site was examined for urinary extravasation during the physiologic and active phases of filling. RESULTS: Hemostasis was achieved, and all collecting system injuries, regardless of size, were free of urinary leakage at physiologic pressures. Moreover, all defects maintained a seal at supraphysiologic pressures of at least 50 cm H(2)O. CONCLUSION: The combined use of fibrin glue and Gelfoam is an effective means to obtain hemostasis and seal collecting system injuries up to 10 mm at physiologic pressures and up to 50 cm H(2)O in the acute setting. Our hope is that this technique can facilitate both laparoscopic and open partial nephrectomies. New technologies will be employed in an attempt to obtain better seating of the sealant plug in the future. Survival studies are in progress.

Animals↗

PubMed2003

A phase I study of paclitaxel, estramustine phosphate and vinorelbine (Pacl-E-Vin) in advanced malignancies: triple tubulin targeting.

Anti-tubulin couplets have activity in hormone-resistant prostate cancer. This study was designed to define the dose-limiting toxicity (DLT) and recommended phase II dose (RPTD) of the unique triplet combination of paclitaxel, estramustine phosphate (EMP) and vinorelbine (Pacl-E-Vin). Patients with advanced malignancies who had failed standard therapy, ECOG performance status (PS 0-2) and adequate organ function were included. Dose of EMP was fixed at 300 mg/m2/dose p.o. t.i.d. on days 1-3 and 8-10. Vinorelbine dose was 20 mg/m2/day i.v. on days 3 and 10. Paclitaxel was dose escalated from 40 to 50 mg/m /day i.v. on days 3 and 10. Cycles were repeated every 3 weeks. Twelve adults (median age 72) were entered on this study. Primary tumors included prostate (n=7), cervix (n=2), melanoma (n=1), colon (1) and lung with synchronous prostate cancer (n=1). Nine patients had received no prior chemotherapy, one had received a prior regimen and two had received two or more prior regimens. Of four evaluable patients at dose level 1, one patient had grade 3 neutropenia leading to the day 10 dose being withheld. Of five evaluable patients at dose level 2, there was one DLT (febrile neutropenia) and two grade 3 neutropenias leading to the day 10 dose being withheld. One patient had a lower extremity deep vein thrombosis. Other side effects were mild and reversible. Nine patients were evaluable for efficacy: three with prostate cancer had a greater than 50% prostate-specific antigen (PSA) response, and a patient with synchronous prostate and lung cancer had a greater than 50% PSA response. We conclude that the DLT of Pacl-E-Vin is neutropenia. RPTD is vinorelbine 20 mg/m2, paclitaxel 40 mg/m2, both administered on days 3 and 10, and EMP 900 mg/m2/day on days 1-3 and 8-10, q3w. Dose omission at day 10 followed by 20% dose reduction of paclitaxel and vinorelbine is recommended in the event of grade 3 neutropenia. Activity in hormone-refractory prostate cancer is promising and warrants phase II evaluation.

Adult↗

PubMed2003

Altered expression of p27 and Skp2 proteins in prostate cancer of African-American patients.

PURPOSE: The purpose is to investigate the clinical relevance of altered patterns of p27 and Skp2 expression in African-American patients with localized prostate cancer. The abundance of p27, an inhibitor of cell proliferation, is controlled by Skp2-dependent proteolysis. EXPERIMENTAL DESIGN: A well-characterized cohort of 162 African-Americans who underwent radical prostatectomy at the Veterans Affairs Medical Center of New York between 1990 and 2000 was studied. We analyzed p27 and Skp2 expression by immunohistochemistry. Altered expression of p27 (defined as <40% tumor cells expressing the protein) and Skp2 (defined as > or ==" BORDER="0">20% tumor cells expressing the protein) were correlated with clinicopathological parameters and time to prostate-specific antigen (PSA) recurrence. RESULTS: Altered expression of p27 and Skp2 was observed in 112 of 162 (69.1%) and 93 of 162 (57.4%) cases, respectively. Inverse patterns of Skp2 and p27 protein expression were seen in 87 of 162 (53.7%) cases. A marginally significant association was found between Skp2 overexpression and extracapsular extension (P = 0.065). Moreover, patients with Skp2 overexpression had a 2.77 years decreased median time to PSA recurrence compared with patients with low Skp2 expression; however, the difference was not statistically significant. In multivariate analysis, only tumor grade and stage independently predicted PSA recurrence in this cohort. CONCLUSIONS: Our data suggest a role for Skp2 overexpression in prostate cancer pathogenesis that might not be exclusively related to p27 degradation. More studies are needed to determine the mechanistic role of Skp2 in prostate cancer.

Black or African American↗