Purpose
There is a potential benefit with concurrent statin use and neoadjuvant therapy for rectal cancer. The impact of statins on pathologic response following short-course neoadjuvant radiation has yet to be studied. This study aimed to elucidate the impact statin use on tumor response to short-course neoadjuvant radiation.
Methods
This retrospective cohort study included patients receiving short-course neoadjuvant radiation and subsequently undergoing oncologic resection for stage II/III rectal adenocarcinoma from 2014–2020. Exclusion criteria included recurrent disease, total neoadjuvant therapy (TNT), and oncologic resection less than six weeks after neoadjuvant therapy. The primary outcome was pathologic complete response (pCR). Secondary outcomes included graded pathologic response and incidence of radiation-associated toxicity. Univariable logistic regressions and stepwise multivariable logistic regressions were performed.
Results
Seventy-nine patients (mean age: 68.6 ± 11.2 years, 39.2% female) met inclusion criteria. Prior to neoadjuvant therapy, median T-stage was 3 (range: 1–4), median N-stage was 1 (range: 0–2), and mean tumor distance from the anal verge was 6.3cm (± 2.9). Thirty-five patients (44.3%) were using statins. Overall, 7.6% experienced pCR and 29.1% had no treatment response on pathology. Radiation-associated toxicity was 43.0%. Statin use was not associated with pCR (OR 2.71, 95%CI 0.47–15.7, p = 0.27), however on stepwise multivariable logistic regression, statin use was associated with decreased prevalence of no response (OR 0.08, 95%CI 0.01–0.43, p = 0.003).
Conclusions
Statins may offer a synergistic effect when given concurrently with short-course neoadjuvant radiation for rectal cancer. Further prospective study evaluating the use of statins in conjunction with neoadjuvant therapy is warranted.