The cases of anal squamous cell cancer (SCCA) are increasing over time. Even though chemoradiotherapy provides a chance to cure, some patients are known to develop recurrence or have a lack of complete response to the treatment procedure. This study assessed the value of inflammation-based indicators, including the modified Glasgow Prognostic Score and neutrophil:lymphocyte ratio, in patients with SCCA treated by CRT with the intention of cure. Medical records were reviewed, and clinical, pathological, and treatment characteristics were summarized. The mGPS and NLR were calculated from routine blood tests obtained before CRT.

In total, 118 patients underwent CRT  for anal squamous cell cancer between 2007-2018. As indicated by NLR >3 and mGPS >0, systemic inflammation was present in 41% and 39% of patients, respectively. Most patients had T2 or larger tumors without nodal involvement. An elevated mGPS was associated with a more advanced T-stage. On multivariate analysis, more advanced T-stage and a raised mGPS were independently related to incomplete CRT response. Just like it was measured by the mGPS, systemic inflammation was associated with an incomplete CRT response and is independent of the inferior survival rates in patients with SCCA. Hence, mGPS now offers a clinical marker of inferior outcome that identifies high-risk patients.