Ex Situ Study of the Effectiveness of Enucleation In Patients with Renal Cell Carcinoma

Abstract

We wished to identify the efficacy of enucleation (excavation) in the treatment of renal cell carcinoma. Surgical specimens from 26 patients with polar or peripheral lesions, 50 per cent of which were found incidentally by computerized tomography scan, were considered amenable to this form of treatment and were studied by ex situ enucleation after standard radical nephrectomy. Eleven patients were determined to have unsuccessful enucleation after histopathological study demonstrated capsular invasion, vascular invasion, residual tumor in the bed or multicentric tumors. Preoperative computerized tomography assessment did not accurately predict success of enucleation. The presence of a fibrous pseudocapsule of compressed renal parenchyma, which might facilitate a dissection plane and successful enucleation, did not correlate with tumor size. Microscopic examination of pseudocapsular integrity frequently revealed areas of thinning, disruption and penetration by neoplasm. When parenchymal preservation is necessary in the treatment of renal cell carcinoma, as wide a margin of adjacent renal parenchyma as possible should be excised with the tumor. In this study enucleation alone was associated with a significant risk of incomplete excision and, therefore, potential for treatment failure. We do not recommend enucleation in the presence of a normal contralateral kidney.

Histopathologic Analysis of Peritumoral Pseudocapsule and Surgical Margin Status after Tumor Enucleation for Renal Cell Carcinoma

“…Then, from the early 1980s, concurrently with the renewed interest in conservative surgery, many reports evaluated PS and SM status either on an RN specimen or on the sole tumor, but after an ex vivo TE, to investigate the real need to remove a rim of healthy tissue around the tumor. These studies noted some degree of PS invasion with RCC, irrespective of tumor size and histologic subtype, with a higher rate in larger and less-differentiated tumors, and thus TE was not recommended because of the significant risk of incomplete excision, although none histologically analyzed the tumor removed during an in vivo TE [8][9][10]. Indeed, Rocca Rossetti et al noted a continuous PS in 80% of tumors of <7 cm in diameter; in larger tumors this fraction was only 23.5% [8].…”

“…Recently, other retrospective analyses confirmed that TE can be safely used for treating pT1a-pT1b RCC tumors, and it is not associated with any greater risk of local recurrence than is partial nephrectomy [20][21][22][23]. Therefore, the discrepancy between the optimal oncologic results of in vivo TE reported in several recent retrospective analyses [20][21][22][23] and the pathologic concerns of incomplete tumor excision based on data obtained by studies after an ex vivo TE or tumor sections of RN specimens remains an unsolved oncologic issue in conservative kidney surgery [8,[9][10][11].…”

“…The concern about local recurrence due to inadequate tumor excision and the reported risk of pseudocapsule (PS) invasion on the parenchymal side [7][8][9][10][11] led most surgeons to remove a minimal rim of normal-appearing parenchyma around the tumor, and at present this is considered to be the technique of choice in patients undergoing NSS [1,2]. Nevertheless, in recent years there have been several reports on the reduction of the thickness of the safety margins that should be excised with the tumor to avoid the risk of local recurrence.…”

170 Long-Term Results of Simple Enucleation for the Treatment of Small Renal Cell Carcinoma

“…Tumor enucleation has been shown to be effective in providing intermediate cancer-free intervals in patients with peripheral lesions (17,18). However, other authors reported increasing as compared with the partial nephrectomy incidence of local recurrences after simple enucleation (19,20). We think, this can be explained by the blunt finger enucleation technique instead of sharp dissection and improper patient selection.…”

Imperative Indications for Conservative Surgery for Renal Cell Carcinoma: 20 Years’ Experience

“…This evidence may depend on an incomplete tumor dissection or on a multifocal renal tumor. Rosenthal et al [15] and Blackley et al [16] showed that the pseudocapsule of the tumor is not a uniform and homogenous structure, but presents many breaks and neoplastic infiltrations (fig. 3); therefore, tumor dissection must be performed at the distance of 5 mm around the neoplasm ( fig.…”