ECE2018 Poster Presentations: Adrenal and Neuroendocrine Tumours Endocrine tumours and neoplasia (34 abstracts)
1Internal Medicine, Department of Clinical and Biological Sciences, University of Turin, Orbassano, Italy; 2Statistical Unit, Department of Clinical and Biological Sciences, University of Turin, Torino, Italy; 3Pathology Unit, Department of Oncology, University of Turin, Orbassano, Italy.
Background and objectives: The role of adjuvant mitotane therapy after radical surgery for adrenocortical carcinoma (ACC) is still debated. The aim of our study is to assess the effects of adjuvant mitotane on recurrence free survival (RFS) and overall survival (OS) in non-metastatic ACC patients and to evaluate prognostic factors in adjuvant setting.
Methods: Retrospective data were collected from 152 patients affected by ACC (stage I-III) referred to our center from 1988 to 2015. One hundred patients underwent adjuvant mitotane therapy (mitotane group), while 52 patients did not receive any treatment after surgery (control group). The following potential prognostic factors were investigated with univariate and multivariate analysis: age at diagnosis, endocrine activity of the tumor, ENSAT tumor stage, R status, Weiss score, mitotic count, Ki-67, plasma mitotane levels.
Results: Although the patients on mitotane had a worse prognostic profile (higher Weiss score, mitotic count and Ki-67), we observed a significant increase in RFS of the mitotane group (median 37 [4199] vs 21 months [4180], HR 2.79 [1.584.91], P<0.001), while OS was not significantly different between the two groups (median 58 [8199] vs 50 months [4231], HR 1.22 [0.612.42]). In multivariate analysis hormonal secretion, Weiss score, mitotic count and Ki-67 were negative prognostic factors for RFS. The same factors with tumor stage were associated with a shorter OS.
Conclusions: Adjuvant mitotane therapy was associated with prolonged RFS in ACC patients. An effect on OS was not apparent but a longer follow-up is likely needed to evaluate any treatment-related difference.