Systematic Review and Meta-Analysis-Is there a Benefit in Using Neoadjuvant Systemic Chemotherapy for Locally Advanced Penile Squamous Cell Carcinoma?

Purpose: Neoadjuvant chemotherapy is a recommended treatment for patients with penile cancer with bulky inguinal lymphadenopathy or unresectable primary tumors, although there is no evidence of its benefit from randomized trials.

Materials and methods: We conducted a systematic search in Embase® and MEDLINE® for studies reporting on patients who received preoperative neoadjuvant chemotherapy for locally advanced penile squamous cell carcinoma. Objective response rate, pathological complete response, grade 3 or greater toxicity and overall mortality were evaluated in terms of neoadjuvant chemotherapy type, which was dichotomized as nontaxane-platinum and taxane-platinum regimens.

Results: Overall 10 studies met the inclusion criteria, enrolling a total of 182 patients, with 66 (36.3%) and 116 (63.7%) treated with nontaxane-platinum and taxane-platinum regimens, respectively. The pooled results demonstrated an objective response rate of 53% (95% CI 42-64), pathological complete response rate of 16%, grade 3 or greater toxicity rate of 40% (95% CI 19-64) and overall mortality of 55% (95% CI 40-70) in patients treated with neoadjuvant chemotherapy. Stratified subanalysis revealed an objective response rate of 55% and 49%, a pathological complete response of 9% and 20%, a toxicity rate of 26% and 49%, and an overall mortality of 54% and 58% for nontaxane-platinum vs taxane-platinum regimens, respectively.

Conclusions: The pooled findings in this study suggest that approximately 50% of the patients with bulky regional lymph node metastases from penile cancer respond to platinum based neoadjuvant chemotherapy and approximately 16% of patients achieve a pathological complete response. Nontaxane based regimens appear to be better tolerated than taxane regimens based on reported grade 3 or greater adverse events (26% vs 49%). Ultimately the robustness of these observations should be interpreted with an awareness of the inherent limitations of deriving data from a collection of small, heterogeneous series.