Preoperative predictors of malignancy and unfavorable pathology for clinical T1a tumors treated with partial nephrectomy: A multi-institutional analysis

Abstract

Purpose To determine preoperative predictors associated with RCC and unfavorable pathology in small renal masses treated with partial nephrectomy (PN). Materials and Methods PN records from 5 centers were retrospectively queried for patients with a clinically localized, single tumor < 4 cm on imaging (cT1a). Between 2007 and 2013, 1009 patients met inclusion criteria. Unfavorable pathology was defined as any grade III or IV RCC or tumors upstaged to pathologic T3a disease. Logistic regression models were used to determine preoperative characteristics associated with RCC and with unfavorable pathology. Results A total of 771 (76.4%) patients were found to have RCC and 198 (19.6%) had unfavorable pathology. On multivariate, bootstrap-adjusted logistic regression analysis, factors associated with presence of malignancy were imaging tumor size > 3 cm (OR 1.46, p = 0.040), male sex (OR 1.88, p < 0.0001) and nephrometry score > 8 (OR 1.64, p = 0.005). These same factors were independently associated with risk of unfavorable pathology: size > 3 cm (OR 1.46, p=0.021), male sex (OR 2.35, p < 0.0001) and nephrometry score > 8 (OR 1.49, p =0.015). The c statistic was 0.62 for the predicting malignancy and 0.63 for unfavorable pathology. Conclusions In this multi-institutional cohort, male sex, imaging tumor size >3 cm, and nephrometry score >8 were predictors of RCC and adverse pathology following PN. These factors may assist in risk stratification and selective renal mass biopsy prior to decision making. Further studies are necessary to validate these findings.

Increased use of partial nephrectomy to treat high‐risk disease

“…Recent research has shown that higher tumour complexity (nephrometry score ≥8) is an independent predictor of unfavourable RCC pathology, i.e. high‐grade or pT3 disease . Therefore, it is possible that increased PN use for higher complexity tumours, as reported in the literature, has contributed to this trend .…”

Five-year Analysis of a Multi-institutional Prospective Clinical Trial of Delayed Intervention and Surveillance for Small Renal Masses: The DISSRM Registry

“…The only finding that would push such a patient to intervention is PRB identification of high-grade or sarcomatoid RCC, which is not reliably detected, will likely exhibit a rapid GR and trigger subsequent intervention, and may not impact OS. We do recommend PRB for two distinct groups of patients: (1) those with intermediate risk of competing illness and progression of disease, for whom more information may help in making a decision regarding PI or AS; and (2) those with a high likelihood of benign disease (young women with tumors 3 cm) [22][23][24]. It E U R O P E A N U R O L O G Y X X X ( 2 0 1 5 ) X X X -X X X should be recognized that PRB may provide important tissue and identify benign lesions for a clearer understanding of oncologic outcomes in the AS cohort.…”

Partial vs Radical Nephrectomy for T1-T2 Renal Masses in the Elderly: Comparison of Complications, Renal Function, and Oncologic Outcomes

“…Our center is increasingly integrating clinical data, 22 with renal mass biopsy 23 and nuclear imaging data, 24 to better determine which patients may be spared from surgical resection. However, for many patients in this 12-year series, these methods were unavailable or infrequently used at the time of their diagnosis.…”