The Use of Trimodality Treatment in Patients With Locally Advanced Oesophageal Squamous Cell Carcinoma: An Experience From a Large Cancer Centre in Pakistan.

Introduction Esophageal cancer is one of the most common cancers worldwide. Neoadjuvant chemoradiotherapy followed by surgery is the standard treatment for locally advanced squamous cell carcinoma (SCC). Pathological complete response (pCR) after surgery is associated with better outcomes in terms of overall survival and disease-free survival. We aim to determine the effectiveness of neoadjuvant chemoradiotherapy in patients with locally advanced SCC at our institute, the largest purpose-built cancer center in Pakistan. We also aim to identify various factors influencing pCR, such as chemotherapy regimen, total radiation dose, clinical stage at presentation, and gender. Materials and methods This is a retrospective review of all patients with esophageal SCC presented between January 2019 and 2021 to the institute for treatment. Patients received neoadjuvant chemoradiotherapy (nCRT) as per the CROSS trial protocol, followed by surgery. We assessed the pCR rate. Statistical analyses were performed using IBM SPSS Statistics for Windows, Version 22 (Released 2013; IBM Corp., Armonk, New York). pCR was studied alongside associated factors such as age, gender, stage of disease, chemotherapy regimen, and total dose of radiotherapy. A p-value of <0.05 was considered statistically significant. The chi-square test was used to compare categorical variables. Univariate and multivariate logistic regression was employed to evaluate factors affecting pCR. Results A total of 218 patients were included in the study. pCR was achieved in 64.2% of the patients. The female gender was associated with better outcomes, as 70.4% (n=81) of female patients achieved a complete pathological response, compared to 57.3% (n=59) of males, with a p-value of 0.03. On univariate analysis, the complete pathological response was 69.6% (n=94) in the age group of 45 years and below, whereas it was 55.4% (n=46) in the age group above 45 years, with a p-value of 0.024. Though statistically insignificant, outcomes were slightly better for those with node-negative disease, as 67.2% (n=41) achieved complete pathological response compared to those with node-positive disease at 63.1% (n=99). Univariate logistic regression analysis identified gender (p=0.044, OR=1.77, 95% CI: 1.016-3.108) and age group (p=0.034, OR=1.844, 95% CI: 1.046-3.252) as significantly associated with pCR. Female patients were 77% more likely to achieve pCR compared to male patients (OR=1.77, 95% CI: 1.016-3.108). Younger patients (≤45 years) were 84.4% more likely to achieve pCR compared to the older age group (OR=1.844, 95% CI: 1.046-3.252). However, these did not maintain significance in multivariate logistic regression analysis. Conclusion Our study indicated a high rate of pCR with nCRT in patients with esophageal SCC compared to other studies. The achievement of pCR was higher among females and younger patients, which was statistically significant on univariate logistic regression analysis. Our study also concluded that a higher dose of RT (50Gy/25#) is not superior to a lower dose (45Gy/25#) in terms of pCR achievement but was statistically insignificant. Similarly, CARBO/PAC was not superior to CIS/CAP in terms of pCR achievement and was also statistically insignificant.