Current therapeutic strategies for anal squamous cell carcinoma in Japan

In Western countries, chemoradiotherapy (CRT) is well established as the standard therapy for stages II/III anal squamous cell carcinoma (ASCC). In Japan, the therapeutic modalities for and outcomes of this disease have not been clarified because ASCC is quite rare. The Colorectal Cancer Study Group of the Japan Clinical Oncology Group (JCOG-CCSG) conducted a survey to determine the current therapeutic strategies for ASCC in Japan.

In July 2006, a questionnaire was sent to 49 institutions affiliated with the JCOG-CCSG to gather information on numbers of cases, therapeutic modalities, and outcomes. The target subjects were patients with stages II/III ASCC, diagnosed from January 2000 to December 2004, who were 20-80 years of age with normal major organ function and no severe complications.

Replies were received from 40 institutions. A total of 59 patients satisfied the subject criteria. Detailed information was obtained for 55 subjects; 25 (45%) had stage II ASCC and 30 (55%) had stage III ASCC. CRT was performed in 25 patients (45%); surgery in 17 (31%); surgery combined with radiotherapy (RT), chemotherapy, or CRT in 8 (15%); and RT in 5 (9%). Complete response rate in CRT was 80% (20/25). The 3-year progression-free survival rates for all subjects and for CRT-only subjects were 67% and 77%, respectively.

From 2000 to 2004, only 59 patients with ASCC were identified in the JCOG-CCSG survey and about half of them underwent CRT.