Impact of treatment volume on outcomes for patients with penile cancer at relatively low-volume centers in Japan.

OBJECTIVES

To investigate whether there are differences in treatment approaches, including complications according to the volume of treatment experience for penile cancer, and whether such differences affect patient prognosis.

METHODS

We retrospectively analyzed 196 patients with penile cancer treated at 12 university hospitals and affiliated institutions (total of 32 institutions) in the Kyushu-Okinawa region from 2009 to 2020. Cancer-specific survival (CSS) was compared between patients treated at lower-volume centers (defined as institutions with fewer than five cases during the study period) and higher-volume centers (five or more cases). The underlying factors contributing to differences in CSS were also analyzed.

RESULTS

Groups treated at lower-volume and higher-volume centers comprised 39 and 157 patients, respectively. No significant differences were observed in patient backgrounds. However, among patients with clinical stage 3 disease, CSS was significantly worse in the lower-volume center group. In that subgroup, significantly fewer patients underwent lymph node dissection. There were no notable differences in other treatments or complications between the two groups.

CONCLUSION

A disparity in CSS was observed specifically in patients with clinical stage 3 disease. The lower rate of lymph node dissection in lower-volume centers appears to be a contributing factor to the inferior prognosis in this group. No other differences were found in treatment or complication rates, suggesting that lower-volume centers can deliver care that is comparable to that in higher-volume centers, apart from lymph node dissection.