Definitive Radiotherapy for Squamous Cell Carcinoma of the Anal Canal

Outcomes after intensity-modulated compared with 3-dimensional conformal radiotherapy with chemotherapy for squamous cell carcinoma of the anal canal

Purpose

We report our institution's treatment techniques, disease outcomes, and complication rates after radiotherapy for the management of anal canal carcinoma with intensity-modulated radiotherapy (imrt) and concurrent chemotherapy relative to prior cases managed with 3-dimensional conformal radiotherapy (3D-crt).

Methods

In a retrospective review of the medical records of 21 patients diagnosed with biopsy-proven stage i (23%), stage ii (27%), or stage iii (50%) squamous-cell carcinoma of the anal canal treated with curative chemotherapy and imrt between July 2009 and December 2014, patient outcomes were determined. Results for patients treated with 3D-crt by the same group were previously reported. The median initial radiation dose to the pelvic and inguinal nodes at risk was 45 Gy (range: 36-50.4 Gy), and the median total dose, including local anal canal primary tumour boost, was 59.4 Gy (range: 41.4-61.2 Gy). Patients received those doses over a median of 32 fractions (range: 23-34 fractions). Chemotherapy consisted of 2 cycles of concurrent fluorouracil-cisplatin (45%) or fluorouracil-mitomycin C (55%).

Results

Median follow-up was 3.1 years (range: 0.38-6.4 years). The mean includes a patient who died of septic shock at 38 days. The 3-year rates of overall survival, metastasis-free survival, locoregional control, and colostomy-free survival were 95%, 100%, 100%, and 100% respectively. No patients underwent abdominoperitoneal resection after chemoradiotherapy or required diverting colostomy during or after treatment. Those outcomes compare favourably with the previously published series that used 3D-crt with or without brachytherapy in treating anal canal cancers. Of the 21 patients in the present series, 10 (48%) experienced acute grade 3, 4, or 5 toxicities related to treatment.

Conclusions

The recommended use of imrt with concurrent chemotherapy as an improvement over 3D-crt for management of anal canal carcinoma achieves a high probability of local control and colostomy-free survival without excessive risk for acute or late treatment-related toxicities.

So Now My Patient Has Squamous Cell Cancer: Diagnosis, Staging, and Treatment of Squamous Cell Carcinoma of the Anal Canal and Anal Margin

Squamous cell carcinomas of the anal canal and the anal margin are rare malignancies that are increasing in incidence. Patients with these tumors often experience delayed treatment due to delay in diagnosis or misdiagnosis of the condition. Distinguishing between anal canal and anal margin tumors has implications for staging and treatment. Chemoradiation therapy is the mainstay of treatment for anal canal squamous cell, with abdominoperineal resection reserved for salvage treatment in cases of persistent or recurrent disease. Early anal margin squamous cell carcinoma can be treated with wide local excision, but more advanced tumors require a combination of chemoradiation therapy and surgical excision.

Late gastrointestinal toxicity after radiotherapy for anal cancer: a systematic literature review

INTRODUCTION

There is a paucity of data on incidence and mechanisms of long-term gastrointestinal consequences after chemoradiotherapy for anal cancer. Most of the adverse effects reported were based on traditional external beam radiotherapy whilst only short-term follow-ups have been available for intensity-modulated radiotherapy, and there is lack of knowledge about consequences of dose-escalation radiotherapy.

METHOD

A systematic literature review.

RESULTS

Two thousand nine hundred and eighty-five titles (excluding duplicates) were identified through the search; 130 articles were included in this review. The overall incidence of late gastrointestinal toxicity was reported to be 7-64.5%, with Grade 3 and above (classified as severe) up to 33.3%. The most commonly reported late toxicities were fecal incontinence (up to 44%), diarrhea (up to 26.7%), and ulceration (up to 22.6%). Diarrhea, fecal incontinence and buttock pain were associated with lower scores in radiotherapy specific quality of life scales (QLQ-CR29, QLQ-C30, and QLQ-CR38) compared to healthy controls. Intensity-modulated radiation therapy appears to reduce late toxicity.

CONCLUSION

Late gastrointestinal toxicities are common with severe toxicity seen in one-third of the patients. These symptoms significantly impact on patients' quality of life. Prospective studies with control groups are needed to elucidate long-term toxicity.

Primary Management of Squamous Cell Carcinoma of the Anal Canal: A 30-year Community Hospital Experience

We reviewed outcomes of 41 patients treated with curative-intent radiotherapy for anal canal carcinoma at a community hospital between 1985 and 2015. Twenty-six (63%) presented with stage I or II disease while 15 (37%) had stage III. Thirty-seven received definitive chemoradiation and 4 radiotherapy alone. Thirteen (31.7%) received ≤59.4Gy. Thirty-two (78%) were treated with 3-dimensional conformal radiotherapy while 9 (22%) received intensity-modulated radiotherapy. At 5 years, local control, regional control, freedom from distant metastasis, cause-specific survival, and overall survival were 80%, 98%, 88%, 77%, and 51%. Of those who received >59.4Gy, local control and overall survival were not improved.