Biomedical subjects

Christopher L Amling

Publications and source records attributed to Christopher L Amling.

42 records · Page 3Linked to original sources

PubMed2003

Improved clinical staging system combining biopsy laterality and TNM stage for men with T1c and T2 prostate cancer: results from the SEARCH database.

PURPOSE: A number of studies have failed to show significant differences in outcome following radical prostatectomy between men with palpable, clinically localized prostate cancer (cT2) and those whose tumors are not palpable (cT1c). We determined whether we could improve the prognostic value of the TNM staging system in men with cT1c and cT2 cancers by including information on whether prostate needle biopsy was unilaterally or bilaterally positive. MATERIALS AND METHODS: A retrospective survey of 992 patients from the SEARCH (Shared Equal Access Regional Cancer Hospital) Database treated with radical prostatectomy at 4 equal access medical centers between 1988 and 2002 was done. TNM 1992 clinical stage was T1c in 421 patients, T2a in 287, T2b in 202 and T2c in 82. Multivariate analysis was used to examine whether biopsy laterality and clinical stage were significant predictors of surgical margin status, nonorgan confined disease, seminal vesicle invasion, and time to prostate specific antigen (PSA) recurrence following radical prostatectomy. RESULTS: Patients with clinical stages T2b and T2c cancers had similar rates of PSA recurrence, which were significantly higher than in patients with T1c and T2a disease, who also had similar rates of PSA recurrence. Bilateral positive biopsy further stratified patients with T1c and T2a disease (p = 0.01) but not those with T2b and T2c cancers (p = 0.207). Grouping these 1992 clinical stages with biopsy laterality resulted in a new clinical staging system, which was a significant predictor of PSA recurrence following radical prostatectomy (p <0.001). On multivariate analysis whether TNM clinical stage was evaluated as a categorical or continuous variable only PSA, biopsy Gleason score and the new clinical staging system (1992 TNM stage groupings combined with biopsy laterality) were significant independent predictors of time to biochemical recurrence following radical prostatectomy. CONCLUSIONS: Combining low (T1c and T2a) and high (T2b and T2c) risk 1992 clinical stages with biopsy laterality (unilateral versus bilateral positive) resulted in a new clinical staging system that was a stronger predictor of PSA recurrence following radical prostatectomy than the 1992 or 1997 TNM clinical staging system. If confirmed at other centers and in men who undergo with other treatment modalities, consideration should be given to revising the current TNM staging system to reflect these findings.

Biopsy, Needle↗

PubMed2002

Prospective comparison of computerized tomography and excretory urography in the initial evaluation of asymptomatic microhematuria.

PURPOSE: The ideal imaging study for evaluation of the upper urinary tract in patients with microhematuria has been debated. We prospectively compared the diagnostic yield of computerized tomography (CT) to excretory urography (IVP) in the initial evaluation of asymptomatic microhematuria. MATERIALS AND METHODS: Between December 1998 and June 2001, 115 patients presenting with asymptomatic microhematuria underwent CT and IVP before cystoscopy. Helical CT images with 5 mm. adrenal and kidney slices with and without contrast material were followed by delayed 5 mm. ureteral contrast images through the bladder base. Each CT and IVP was examined by a radiologist who was blinded to the result of the other imaging study. Diagnostic yields of the imaging techniques were compared using the test of 2 proportions and chi-square analysis. RESULTS: Radiographic abnormalities were noted on CT or IVP in 38 patients. Sensitivity was 100% for CT and 60.5% for IVP, and specificity 97.4% for CT and 90.9% for IVP. CT accuracy was 98.3% compared to IVP accuracy which was 80.9% (p <0.001). A total of 40 nonurological diagnoses were made by CT, including 3 abdominal aortic aneurysms and 1 iliac artery aneurysm. No additional diagnoses were made by IVP. Fewer additional radiographic studies were recommended after CT than after IVP. CONCLUSIONS: The use of CT in the initial evaluation of asymptomatic microhematuria results in better diagnostic yield. In addition, more nonurological diagnoses can be made and less additional radiography is needed to confirm a diagnosis.

Aortic Aneurysm, Abdominal↗

PubMed2002

Race as an outcome predictor after radical prostatectomy: results from the Shared Equal Access Regional Cancer Hospital (SEARCH) database.

OBJECTIVES: Whether race is an independent predictor of prostate-specific antigen (PSA) recurrence after RP is controversial. To compare racial differences in clinical and pathologic features and biochemical recurrence in men undergoing radical prostatectomy (RP), we used a newly established multicenter database of patients from four equal-access healthcare centers in California, the Shared Equal Access Regional Cancer Hospital (SEARCH) database. METHODS: A retrospective survey of 1547 patients treated with RP at four different equal-access medical centers in California between 1988 and 2001 was undertaken. Race was categorized as white (n = 1014), black (n = 338), or nonwhite-nonblack (n = 195). Patients were analyzed for racial differences in preoperative variables (age at surgery, clinical stage, PSA, and biopsy Gleason score) and surgical variables (pathologic stage, surgical Gleason score, incidence of seminal vesicle invasion, positive surgical margins, capsular penetration, and pelvic lymph node involvement). Patients were followed up for PSA recurrence. Multivariate analysis was used to determine whether race was an independent predictor of biochemical failure. RESULTS: Significant differences were found among the races in the preoperative factors of clinical stage, age, serum PSA, and biopsy Gleason score, although the absolute differences were small. No differences were found among the races in the pathologic features of the RP specimens, including Gleason score, pathologic stage, and incidence of positive surgical margins, capsular penetration, seminal vesicle invasion, or lymph node involvement. In both univariate and multivariate analyses, only serum PSA (P <0.001) and biopsy Gleason score (P <0.001) were significant independent predictors of time to biochemical recurrence. CONCLUSIONS: In a large multicenter cohort of patients from four equal-access medical care facilities in California, although racial differences were found in clinical stage, age, biopsy Gleason score, and serum PSA level at diagnosis, we found race was not an independent predictor of biochemical recurrence after RP. Race should not be used in models or nomograms predicting PSA failure after RP. The current study represents the largest series of black patients and the first large series of nonwhite-nonblack patients treated with RP reported to date. The Shared Equal Access Regional Cancer Hospital database is a valuable resource for studying patients treated with RP.

Adenocarcinoma↗

PubMed2002

Effect of race on biochemical disease-free outcome in patients with prostate cancer treated with definitive radiation therapy in an equal-access health care system: radiation oncology report of the Department of Defense Center for Prostate Disease Research.

PURPOSE: To report on the first collaboration of the Department of Defense Center for Prostate Disease Research concerned with the relationship between African American race and biochemical disease-free outcomes after definitive radiation therapy. MATERIALS AND METHODS: Information from the medical records of 1,806 patients (1,349 white, 343 African American, 42 of "other" races, and 72 of "unknown" races) treated with definitive radiation therapy between 1973 and 2000 was reviewed. Patients receiving adjuvant hormonal therapy or postoperative adjuvant or salvage radiation therapy were excluded. Biochemical failure was calculated in over 96% of cases by using ASTRO criteria; patients with fewer than three follow-up visits were considered to have biochemical failure with a prostate-specific antigen (PSA) value more than 10-fold the previous value or with any value greater than 50.0 ng/mL. Median radiation therapy doses were similar. The median follow-up was 58.4 months. Kaplan-Meier tests, Cox proportional hazards regression analysis, and log-rank tests were used for data analysis. RESULTS: There was no statistically significant difference in biochemical disease-free survival according to race when patients were stratified according to T stage. African American race conferred a negative prognosis for patients with lesions of Gleason biopsy score 7 (P =.004) but not for patients with lesions of Gleason score 2-4 (P =.14), 5-6 (P =.79), or 8-10 (P =.86). Similarly, African American race conferred a negative prognosis in patients with PSA values of 20.1-50.0 ng/mL (P =.01) at presentation but not in patients with PSA values less than or equal to 4.0 ng/mL (P =.84), 4.1-10.0 ng/mL (P =.71), 10.1-20.0 ng/mL (P =.75), or above 50.0 ng/mL (P =.15) at presentation. At multivariate analysis, race was not a statistically significant predictor of outcome. CONCLUSION: In the equal-access health care system of the Department of Defense, African American race is not associated with a consistently negative prognosis in patients treated with definitive radiation therapy for prostate cancer. Race appears to confer a negative prognosis only in patients with advanced disease at presentation.

Adult↗

PubMedDate not supplied

The association between obesity and the progression of prostate and renal cell carcinoma.

Obesity has been linked to the incidence and mortality of several malignancies, including prostate and renal cancer. Increased body mass appears to have a more consistent association with prostate cancer mortality than incidence and recent studies suggest that it may be related to higher recurrence rates after radical prostatectomy. Obesity has an even stronger association with the development and progression of renal cancer, particularly in women. Since obesity is one of few modifiable risk factors that may impact the clinical course of these cancers, lifestyle and dietary changes to limit obesity should be recommended.

Carcinoma, Renal Cell↗

PubMedDate not supplied

Transureteral saline perfusion to obtain renal hypothermia: potential application in laparoscopic partial nephrectomy.

BACKGROUND: Partial nephrectomy for resection of renal tumors often requires renal artery clamping and external renal cooling using ice-slush. Laparoscopic surgery precludes traditional ice-slush cooling. To facilitate renal cooling during laparoscopic partial nephrectomy, we investigated a method of intrarenal cooling by retrograde transureteral iced saline perfusion. METHODS: Open laparotomy was performed in 6 pigs. After atraumatic renal artery clamping, one kidney was cooled externally by using standard ice-slush; the other was cooled transureterally. For transureteral cooling, the ureter was cannulated with a double lumen 12 Fr catheter. Chilled saline (4 degrees C) irrigation was flushed through the catheter into the renal pelvis (16.7 mL/min) and allowed to drain via the second lumen of the catheter. Using a 30-gauge hypodermic thermometer, kidney temperatures were measured at 5-minute intervals for 30 minutes at 3 locations and 2 depths (0.5 cm and 1.5 cm). The animals were euthanized, and the kidneys were harvested for histologic examination. RESULTS: Renal cooling was achieved with both external and transureteral cooling. However, lower (5.0 versus 26.1 degrees C, P<0.001) parenchymal temperatures were achieved more rapidly with external renal cooling. During transureteral cooling, medullary (1.5 cm) temperatures were lower than cortical (0.5 cm) temperatures were; this difference did not reach statistical significance. CONCLUSIONS: Although renal hypothermia can be achieved by transureteral iced saline infusion, external cooling by using ice-slush appears to be more efficient in the porcine model. With refinement of the technique, intrarenal cooling via a transureteral approach may allow more effective cooling of the renal medulla, and limit warm ischemia during laparoscopic partial nephrectomy.

Animals↗