Cancer Research, Statistics, and Treatment (Jan 2023)

Outcomes of squamous cell carcinoma of the anal canal: A retrospective observational study from a regional cancer institute in South India

  • M N Arunkumar,
  • Alexander John,
  • Selvaluxmy Ganesharajah,
  • Venkatraman Radhakrishnan

DOI
https://doi.org/10.4103/crst.crst_281_22
Journal volume & issue
Vol. 6, no. 1
pp. 37 – 43

Abstract

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Background: Squamous cell carcinoma of the anal canal is a rare malignancy accounting for 2% of all gastrointestinal malignancies. Indian data regarding the outcomes of anal canal carcinoma and the factors influencing them are sparse. Objective: The study aimed to assess the survival and prognostic factors affecting the outcomes of patients with squamous cell carcinoma of the anal canal. Materials and Methods: This was a retrospective observational study of patients with squamous cell carcinoma of the anal canal, treated at the Cancer Institute, Chennai, India, from January 2000 to December 2015. Data were captured from the electronic medical records of the hospital-based cancer registry of the Cancer Institute. Progression-free survival and overall survival (OS) were calculated with the use of the Statistical Package for the Social Sciences software. Results: We included 86 patients in this study. There were 66 (77%) patients treated with concurrent chemoradiation, and the remaining 20 (23%) received radiation alone. The median follow-up was 61 months (range, 2-190). The 5-year OS in the patients who were treated with chemoradiation was 60.4%, compared to 44.4% in those who received radiation alone (Hazard ratio [HR], 1.79; 95% confidence interval [CI], 0.96-3.31; P = 0.059). On univariate analysis, the factors associated with reduced survival were increased tumor size (P = 0.001), higher stage (P = 0.004), and radiation interruption (P = 0.001). On multivariate analysis, tumor size (HR, 2.23; 95% CI, 1.12-4.44; P = 0.022) and radiation interruption (HR, 2.20-95% CI, 1.21-4.02; P = 0.009) remained significant factors in decreasing OS. Conclusion: In addition to the well-established prognostic factors such as tumor stage and grade, treatment factors like radiation treatment interruptions play an essential role in predicting the outcomes of squamous cell carcinoma of the anal canal.

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