The role of hematological parameters in predicting the response to radical chemoradiotherapy in patients with anal squamous cell cancer

Abstract

Background: Historically, the treatment of choice for anal carcinoma (AC) had been abdominoperineal resection (APR), but radical radiotherapy with concurrent 5-fluorouracil plus mitomycin C chemotherapy (CRT) was later established as standard therapy, although with  a failure rate of 20–30%. The aim of this study was to evaluate the outcomes after radical CRT, prognostic and predictive factors and patterns of failure.

Patients and methods: This study included 47 patients treated with radical CRT for patohistologicaly confirmed anal squamous cell carcinoma. Analyzed haematological parameters included: neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and haemoglobin level. Tumor response was assessed at 24 weeks from CRT completion. Follow-up was performed every 3 months during the first two years, and every 6 months thereafter.

Results: A complete clinical response (CR) was detected in 30 patients (63.8%). Patients who did not achieve a 6-months CR and those who had a CR after 6 months but then relapsed were referred to surgical treatment. With combined CRT and surgical salvage treatment CR rate was 80.9%. Patients with CR after 6 months had significantly increased DFS, PFS, and OS. The final logistic regression model included pretreatment haemoglobin level and treatment break period. A significant effect on the 6-month response was confirmed for PLR (p = 0.03).

Conclusions: Important prognostic factors associated with CR were baseline haemoglobin level and period of treatment interruptions. Potential haematological prognostic factors could be PLR and NLR, which can be routinely determined by low-cost and minimally invasive methods.