Background: The objective of this study was to evaluate differences in various clinical endpoints in patients with reconstructive surgery by renal partial nephrectomy for tumors up to 4 cm compared to tumors larger than 4 cm.

Material and methods: A total of 170 partial renal resection patients that presented malignant tumors were included in the retrospective study. Data was analyzed retrospectively based on internal clinic files, as well as a questionnaire to enhance the follow-up clinical outcomes data obtained. The most important outcomes determined included post-operative renal function, intra- and post-operative complications, local recurrence rate and total survival time.

Results: The local recurrence rate was 6.1% for tumors up to 4 cm in size, compared to 14.9% for tumors that were larger than 4 cm. Compared to results for partial resection of T1a tumors, results for partial resection of tumors larger than 4 cm are worse in terms of post-operative renal function (p=0.007), as well as in terms of a total complications rate (p=0.048). It is important to note that there was not only a higher risk of post-operative bleeding that required transfusions (p=0.012), but also a higher risk of a hypertensive episode during the post-operative period reviewed (p=0.022). In addition, the total survival time for patients presenting tumors of up to 4 cm in size was significantly better (p=0.003).

Conclusion: The results of our retrospective study of 170 patients that underwent partial renal resection after the diagnosis of malignant tumors, is that partial renal resection presents an oncologicaly safe surgical solution with low local recurrence rates. Additionally, partial resection in case of tumors that are larger than 4 cm showed worse post-operative renal function, a higher complications rate and a worse survival rate.