Robert Houston Thompson

Mayo Clinic - Rochester, Rochester, Minnesota, United States

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Publications (5)14.75 Total impact

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    ABSTRACT: Objective: To evaluate outcomes of percutaneous ablation of small renal tumors in the elderly population. Patients and Methods: Utilizing our tumor ablation database, we searched for percutaneous ablation procedures for clinical T1a renal masses in octogenarians and nonagenarians between June 2001 and May 2012. Altogether 105 tumors from 99 procedures among 95 patients (mean age 84.0 ± 3.0 years, range 80-92) were identified. Oncologic outcomes and major complications were evaluated. Assessment also included patient hospital stays and renal functional outcomes. Results: Technical success was achieved in 60/61 (98.4%) tumors treated with cryoablation and 43/44 (97.7%) after radiofrequency ablation (RFA). Of 87 renal tumors with at least 3 months imaging follow up, 2 (5.4%) tumors progressed at 1.2 and 2.2 years following RFA. None recurred following cryoablation. Estimated progression-free survival rates at 1, 3, and 5 years following ablation were 99%, 97%, and 97%, respectively. Thirty-four patients died at a mean of 3.7 years following ablation (median 3.7; range 0.4-9.6). Estimated overall survival rates were 98%, 83%, and 61%, respectively. Among 33 patients with sporadic, biopsy-proven renal cell carcinoma, estimated cancer-specific survival rates were 100%, 100%, and 86%, respectively. Five (8.6%) major complications developed after renal cryoablation with no (0%) major complication after RFA. Mean decrease in serum creatinine within one week following ablation was 0.1 mg/dL. Mean hospitalization was 1.2 days. Conclusion: Percutaneous thermal ablation is safe and effective in the active management of clinical T1a renal masses in elderly patients. These results should help urologists appropriately assess expected outcomes when counseling octogenarian and nonagenarian patients.
    Journal of endourology / Endourological Society 11/2014; · 1.75 Impact Factor
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    ABSTRACT: Objectives The neutrophil-lymphocyte ratio (NLR) is an indicator of the systemic inflammatory response. An increased pretreatment NLR has been associated with adverse outcomes in other malignancies, but its role in localized (M0) clear cell renal cell carcinoma (ccRCC) remains unclear. As such, we evaluated the ability of preoperative NLR to predict oncologic outcomes in patients with M0 ccRCC undergoing radical nephrectomy (RN). Methods and materials From 1995 to 2008, 952 patients underwent RN for M0 ccRCC. Of these, 827 (87%) had pretreatment NLR collected within 90 days before RN. Metastasis-free, cancer-specific, and overall survival was estimated using the Kaplan-Meier method and compared using the log-rank test. Multivariate models were used to analyze the association of NLR with clinicopathologic outcomes. Results At a median follow-up of 9.3 years, 302, 233, and 436 patients had distant metastasis, death from ccRCC, and all-cause mortality, respectively. Higher NLR was associated with larger tumor size, higher nuclear grade, histologic tumor necrosis, and sarcomatoid differentiation (all, P<0.001). A NLR≥4.0 was significantly associated with worse 5-year cancer-specific (66% vs. 85%) and overall survival (66% vs. 85%). Finally, after controlling for clinicopathologic features, NLR remained independently associated with risks of death from ccRCC and all-cause mortality (hazard ratio for 1-unit increase: 1.02, P< 0.01). Conclusions Our results suggest that NLR is independently associated with increased risks of cancer-specific and all-cause mortality among patients with M0 ccRCC undergoing RN. Accordingly, NLR, an easily obtained marker of biologically aggressive ccRCC, may be useful in preoperative patient risk stratification.
    Urologic Oncology: Seminars and Original Investigations. 01/2014;
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    ABSTRACT: Grading of renal cell carcinoma (RCC) has prognostic significance, and there is recent consensus by the International Society of Urological Pathology (ISUP) that for clear cell and papillary RCC, grading should primarily be based on nucleolar prominence. Microscopic tumor necrosis also predicts outcome independent of tumor grading. This study was undertaken to assess whether the incorporation of microscopic tumor necrosis into the ISUP grading system provides survival information superior to ISUP grading alone. Data on 3017 patients treated surgically for clear cell RCC, 556 for papillary RCC, and 180 for chromophobe RCC were retrieved from the Mayo Clinic Registry. Median follow-up periods were 8.9, 9.7, and 8.5 years, respectively. Four proposed grades were defined: grade 1: ISUP grade 1+ISUP grade 2 without necrosis; grade 2: ISUP grade 2 with necrosis+ISUP grade 3 without necrosis; grade 3: ISUP grade 3 with necrosis+ISUP grade 4 without necrosis; grade 4: ISUP grade 4 with necrosis or sarcomatoid/rhabdoid tumors. There was a significant difference in survival between each of the grades for clear cell RCC, and the concordance index was superior to that of ISUP grading. The proposed grading system also outperformed the ISUP grading system when cases were stratified according to the TNM stage. Similar results were not obtained for papillary RCC or chromophobe RCC. We conclude that grading for clear cell RCC should be based on nucleolar prominence and necrosis, that ISUP grading should be used for papillary RCC, and that chromophobe RCC should not be graded.
    The American journal of surgical pathology 01/2013; · 4.06 Impact Factor
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    ABSTRACT: It has been reported that Fuhrman grading is not appropriate for chromophobe renal cell carcinoma (RCC). The objective of this study was to determine whether nucleolar grading and the recently described chromophobe RCC grading system by Paner and colleagues provide prognostic information. Pathologic features of 185 patients with chromophobe RCC treated surgically between 1970 and 2006 were reviewed, including nucleolar grade, chromophobe RCC grade, the 2010 TNM groupings, sarcomatoid differentiation, and coagulative tumor necrosis. Cancer-specific (CS) survival was estimated using the Kaplan-Meier method, and associations with CS survival were evaluated using Cox proportional hazard regression models. Twenty-three patients died from RCC at a mean of 3.0 years after surgery (median 1.3; range 0 to 16) with estimated CS rates (95% confidence interval) of 89% (84 to 94), 86% (81 to 92), and 85% (78 to 91) at 5, 10, and 15 years after surgery. Univariate associations with CS survival included the 2010 TNM stage groupings, sarcomatoid differentiation, coagulative tumor necrosis, chromophobe RCC grade, and nucleolar grade (all P<0.001). These last 4 features remained significantly associated with CS survival after adjusting for the 2010 TNM stage groupings. When the analysis was restricted to the 155 patients with nonsarcomatoid TNM stage groupings I and II chromophobe RCC, only stage grouping (I vs. II) was significantly associated with CS survival (P=0.03). Although the chromophobe RCC grading system described by Paner and colleagues and nucleolar grade are associated with CS survival in chromophobe RCC, they add no additional prognostic information once TNM stage and sarcomatoid differentiation are assessed.
    The American journal of surgical pathology 02/2012; 36(6):851-6. · 4.06 Impact Factor
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    ABSTRACT: Prior studies suggest that the renal sinus permits early tumor spread in otherwise localized renal cell carcinoma (RCC) tumors. We hypothesized that renal sinus fat invasion may be unrecognized in pT1 patients who subsequently die from RCC. Between 1985 and 2002, we identified 577 patients who underwent radical nephrectomy for localized pT1 clear cell RCC as reviewed by a single urologic pathologist (J.C.C.). Among these patients, 49 died from RCC including 33 who had their original nephrectomy specimen stored in formalin. These specimens were then resectioned with thin cuts of the renal sinus and reviewed by the same pathologist. For comparison, 33 patients who did not die from RCC (controls) also had their original nephrectomy specimen resectioned. Among the 33 patients who died from seemingly localized RCC, 14 (42%) had previously unrecognized renal sinus fat invasion compared with 2 (6%) of the controls (P<0.001). In addition, 19 (58%) patients who died from RCC had renal sinus small vein (microscopic venous) invasion, a pathologic feature not currently incorporated into the TNM staging system for RCC. This feature was present in 7 (21%) of the controls (P=0.003). In total, 22 (67%) patients who died from RCC had unrecognized renal sinus fat or small vein invasion compared with 7 (21%) of the controls (P<0.001). We conclude that renal sinus fat invasion is an important adverse pathologic feature that is clearly underreported in the literature. Appropriate assessment of nephrectomy specimens should include proper sampling of the renal sinus even for seemingly localized tumors.
    American Journal of Surgical Pathology 07/2007; 31(7):1089-93. · 4.87 Impact Factor