Chemoradiotherapy in squamous cell carcinoma of the anal canal: a single institution experience

Clinical outcomes and prognostic factors of concurrent chemoradiotherapy for anal squamous cell carcinoma in Japan

BACKGROUND

Concurrent chemoradiotherapy (CCRT) is the standard treatment for locoregional anal squamous cell carcinoma (ASCC) in western countries. However, there have been few reports on the clinical outcomes of CCRT in Japan. This study aimed to evaluate the clinical outcomes of CCRT, prognostic factors, and the clinical impact of programmed cell death-ligand 1 (PD-L1) expression of ASCC in Japan.

METHODS

Patients with locoregional ASCC were enrolled between 2007 and 2017. All patients received CCRT consisting of ≥ 45 Gy of radiation, 5-fluorouracil, and mitomycin C. Disease-free survival (DFS), overall survival (OS), and adverse events (AEs) were estimated. Expression of p16 and PD-L1 were assessed by immunohistochemical staining (IHC).

RESULTS

This study included 36 patients, of whom 30 (83.3%) were female. Among the participants, 32 (88.9%) achieved complete clinical remission, while six (16.7%) experienced recurrence. The five-year DFS and five-year OS were 72.2% and 84.7%, respectively. Grades ≥ 3 serious AEs included neutropenia in 10 (27.7%) and perianal dermatitis in eight (22.2%). In a univariate analysis, male sex, lymph node metastasis, and large tumor size were significantly associated with worse outcome. In a multivariate analysis, tumor size was an independent factor associated with short DFS. Of the 30 patients whose biopsy specimens were available for IHC, 29 (96.7%) were positive for p16, and 13 (43.3%) were positive for PD-L1. However, PD-L1 expression did not show any clinical impact.

CONCLUSIONS

The comparative etiology, clinical outcomes, and prognostic factors of CCRT observed in Japanese patients with locoregional ASCC were consistent with western data.

Evaluation of survival outcomes and prognostic factors of carcinoma anal canal at a tertiary cancer center

CONTEXT

Concurrent chemoradiotherapy is considered a standard of care for patients with carcinoma anal canal. Being an unusual malignancy, there is limited Indian data regarding survival outcomes and prognostic factors.

AIM

To evaluate survival outcomes and associated prognostic factors in patients with carcinoma anal canal treated with radical intent.

METHODS AND MATERIAL

Patients with squamous cell carcinoma of the anal canal, treated with radical intent between 2015 and 2019 were included in the study. Data regarding the baseline characteristics of the patients and treatment outcomes were collected and analyzed. Survival rates were estimated using Kaplan-Meier method. To determine survival difference between the groups, log-rank test was used. Multivariate analyses were performed with Cox proportional hazard models and P value < 0.05 was considered significant.

RESULTS

Forty-two patients were identified after applying suitable eligibility criteria. The median age was 55 years (range: 26-80 years).The median follow-up duration was 23.5 months (range: 1.9-51.9 months). The 3-year overall survival (OS), disease-free survival (DFS), and locoregional (LRC) were 78.5%, 53.1%, and 66.4%, respectively. On multivariate analysis, inferior DFS was significantly affected by lack of concurrent chemotherapy (CT) (hazard ratio [HR], 11.50; 95% confidence interval [CI], 1.92-68.78; P = 0.007) and radiotherapy (RT) dose of 45 Gy or less (HR, 35.96; 95% CI, 6.32-204.56; P = 0.000).

CONCLUSION

For patients of carcinoma anal canal, concurrent CT and RT dose are independent prognostic factors influencing DFS.

Concomitant chemoradiotherapy with Cisplatin plus 5-Fluorouracil for anal squamous cell carcinoma

OBJECTIVE

The objective of this study was to evaluate the results of combined chemoradiotherapy using 5-fluorouracil and cisplatin with radiation in treatment of anal squamous cell carcinoma in terms of local control, survival, and toxicity.

PATIENTS AND METHODS

This study included 32 patients with histologically confirmed locally advanced anal squamous cell carcinoma (T1-4 with any N). They received chemotherapy consisted of 5-fluorouracil 1000 mg/m(2)/day on the first 5 and last 5 days of RT, cisplatin 75 mg/m(2) on days 2 and 30. External beam RT consisted of 45Gy/f/25 sessions/5 sessions per week. A boost of 9Gy/5 sessions was given to those who developed complete or partial response.

RESULTS

Median age was 55 years with female to male ratio 2.2:1. Fifty-six percent of them had ECOGPS of 1; moderately differentiated pathology was the most common one (53 %). Thirteen patients (40.6 %) presented with N0 and 56 % presented with T2. None of the patients died of acute complications and none developed grade 4 toxicity. Non-hematological complications were more common than hematological ones. Dermatitis was the most common toxicity (59.3 %) than diarrhea and neurologic one (40.7 %). Anemia was the most frequent hematological adverse event (37.5 %). Complete response was reported in 81.2 %. After median follow-up of 25 months, local recurrence was observed in five patients (15.6 %) as the following: three in the anal canal and two in the inguinal lymph nodes. Three patients (9.4 %) developed distant metastasis (two in the liver and one in the lung), while one patient (3 %) had both local and distant metastases. Three-year overall survival rate (OS) was 81.3 %, while 3-year progression-free survival (PFS) rate was 72 %, and colostomy-free survival was 90 %.

CONCLUSION

Concomitant chemoradiotherapy of 5-fluorouracil and cisplatin with radiotherapy is a highly effective and well-tolerated treatment of anal cancer. But further studies with larger number of patients are needed to support the indication to treat anal cancer using this regimen.

Intensified intensity-modulated radiotherapy in anal cancer with prevalent HPV p16 positivity

AIM: To investigate the toxicity and response of intensity-modulated radiotherapy schedule intensified with a simultaneous integrated boost in anal canal cancer.

METHODS: From March 2009 to March 2014, we retrospectively analyzed 41 consecutive patients treated with intensity-modulated radiotherapy (IMRT) and concurrent chemotherapy for anal canal squamous cell carcinoma at our center. Radiotherapy was delivered via simultaneous integrated boost (SIB) technique by helical tomotherapy, and doses were adapted to two clinical target volumes according to the tumor-node-metastasis (TNM) stage: 50.6 Gy and 41.4 Gy in 23 fractions in T1N0, 52.8 Gy and 43.2 Gy in 24 fractions in T2N0, and 55 Gy and 45 Gy in 25 fractions in all patients with N positive and/or ≥ T3, respectively, to planning target volumes 1 and 2. The most common chemotherapy regimen was 5-fluorouracil and mitomycin-based. Human papilloma virus (HPV) p16 expression was performed by immunohistochemistry and evaluated in the majority of patients. Acute and late toxicity was scored according to CTCAe v 3.0 and RTOG scales.

RESULTS: The median follow-up was 30 mo (range: 12-71). Median age was 63 years (range 32-84). The stage of disease was: stage I in 2 patients, stage II in 13 patients, stage IIIA in 12 patients, and stage IIIB in 14 patients, respectively. Two patients were known to be HIV positive (4.9%). HPV p16 expression status was positive in 29/34 (85.3%) patients. The 4-year progression-free survival and overall survival in HPV-positive patients were 78% and 92%, respectively. Acute grade 3 skin and gastrointestinal toxicities were reported in 5% and 7.3% of patients, respectively; patients’ compliance to the treatment was good due to a low occurrence of severe acute toxicity, although treatment interruptions due to toxicity were required in 7.3% of patients. At 6 mo from end of treatment, 36/40 (90%) patients obtained complete response; during follow-up, 5 (13.8%) patients presented with disease progression (local or systemic).

CONCLUSION: In our experience, intensified SIB-IMRT with chemotherapy is very feasible in clinical practice, with excellent results in terms of overall survival and local control.

Efficacy and toxicity of chemoradiation in patients with anal cancer--a retrospective analysis

Background

Concurrent chemotherapy and radiation therapy is the preferred standard of care for patients with anal cancer. Several studies have suggested a benefit of intensity-modulated radiation therapy (IMRT) compared with 3D-conformal radiation (3D-CRT) regarding acute toxicity. This study evaluates outcome and toxicity of patients undergoing IMRT/Tomotherapy or 3D-CRT at our institution.

Methods

A cohort of 105 anal cancer patients was treated with chemoradiation or radiation alone (16.2%) between January 2000 and December 2011. 37 patients received 3D-CRT while 68 patients were treated with IMRT. Follow-up exams were performed every 3 to 6 months for a minimum of 3 years and then annually.

Results

Median follow-up was 41.4 months (2.8 – 158.4). Overall survival (OS), Progression-free survival (PFS) and local control (LC) at 3 years was 70.3%, 66.5%, 78.3% in the 3D-CRT group and 82.9%, 66.5%, 75.3% in the IMRT group without statistically significant difference. 3-year Colostomy-free survival (CFS) was 85.7% in the IMRT/Tomotherapy group and 91.8% in the 3D-CRT group (p = 0.48). No grade 4 toxicity was found in both groups. Severe (G2/3) acute skin toxicity (94.6% vs. 63.2%; p < 0.001) and acute gastrointestinal toxicity rate (67.6% vs. 47.1%; p = 0.03) was significantly higher with 3D-CRT compared to IMRT/Tomotherapy.

Conclusion

The use of IMRT can reduce acute severe side effects of the skin and gastrointestinal tract but did not demonstrate improved results regarding OS, PFS, LC and CFS.