Diagnosis, clinicopathologic features, treatment, and prognosis of small cell carcinoma of the uterine cervix; Kansai Clinical Oncology Group/Intergroup study in Japan.

Objectives: This is a multicenter, collaborative study to accumulate cases of small cell carcinoma of the uterine cervix (SmCC), to clarify its clinical and clinicopathologic features and prognosis, and to obtain findings to establish future individualized treatment.

Methods: At medical centers participating in the Kansai Clinical Oncology Group/Intergroup, patients diagnosed with SmCC between 1997 and 2007 were enrolled. Clinicopathologic features and prognosis were retrospectively evaluated in patients with SmCC diagnosed at a central pathologic review.

Results: A total of 71 patients were registered at 25 medical centers in Japan. Of these, 52 patients (73%) were diagnosed with SmCC based on a pathological review. These 52 patients diagnosed with SmCC were analyzed. The median follow-up period was 57 months. The 4-year progression-free survival (PFS) was: IB1, 59%; IB2, 68%; IIB, 13%; and IIIB, 17%. The 4-year overall survival (OS) was: IB1, 63%; IB2, 67%; IIB, 30%; IIIB, 29%; and IVB, 25%. For postoperative adjuvant therapy, postoperative chemotherapy (a platinum drug in all cases) was compared to non-chemotherapy. The 4-year PFS was 65% and 14%, and the 4-year OS was 65% and 29%. PFS was significantly better (p=0.002), and the OS tended to be better (p=0.073) in the group with postoperative chemotherapy.

Conclusion: Even in patients with early stage SmCC, the prognosis is poor. However, in early stage patients, by adding postoperative chemotherapy, the prognosis may improve. Currently, various treatment protocols are used at each medical center, but in the future, a standardized treatment protocol for SmCC will hopefully be established.