Radiation Therapy for Anal Squamous Cell Carcinoma: A Retrospective Multicenter Study

Area of Science:

• Oncology
• Radiation Oncology
• Clinical Medicine

Background:

• Anal squamous cell carcinoma presents a significant clinical challenge.
• Radiotherapy (RT) is a primary treatment modality for anal cancer, often combined with chemotherapy.

Purpose of the Study:

• To evaluate treatment outcomes, failure patterns, and prognostic factors in anal cancer patients undergoing definitive radiotherapy.
• To assess the efficacy and safety of RT with concurrent chemotherapy for anal cancer.

Main Methods:

• A retrospective analysis of 83 anal squamous cell carcinoma patients treated with definitive RT between 2000 and 2015.
• Median RT dose of 55 Gy, with 91.6% receiving concurrent chemotherapy (5-fluorouracil plus mitomycin C).

Main Results:

• An overall complete remission rate of 89.2% was observed.
• Five-year survival rates: overall 85.0%, progression-free survival (PFS) 70.4%, locoregional PFS 78.2%, and distant metastasis-free survival 82.6%.
• Eventual treatment response was the sole prognostic factor for overall and PFS. Age, eventual treatment response, initial response, lymph node status, and RT technique influenced survival outcomes.

Conclusions:

• Definitive radiotherapy, particularly with concurrent chemotherapy, demonstrates acceptable treatment outcomes for anal cancer.
• The treatment regimen is associated with safe toxicity profiles.
• Identifying prognostic factors like treatment response is crucial for optimizing patient management.