Nutrition's checkpoint inhibition: The impact of nutrition on immunotherapy outcomes

Objectives: To determine if nutritional status effects response to immunotherapy in women with gynecologic malignancies.

Methods: A retrospective chart review was conducted on gynecologic cancer patients who received immunotherapy at a single institution between 2015 and 2022. Immunotherapy included checkpoint inhibitors and tumor vaccines. The prognostic nutritional index (PNI) was calculated from serum albumin levels and total lymphocyte count. PNI values were determined at the beginning of treatment for each patient and assessed for their association with immunotherapy response. Disease control response (DCR) as an outcome of immunotherapy was defined as complete response, partial response, or stable disease.

Results: One hundred and ninety-eight patients received immunotherapy (IT) between 2015 and 2022. The gynecological cancers treated were uterine (38%), cervix (32%), ovarian (25%), and vulvar or vaginal (4%) cancers. The mean PNI for responders was higher than the non-responder group (p < 0.05). The AUC value for PNI as a predictor of response was 49. A PNI value of 49 was 43% sensitive and 85% specific for predicting a DCR. In Cox proportional hazards analysis, after adjusting for ECOG score and the number of prior chemotherapy lines, severe malnutrition was associated with progression-free survival (PFS) (HR = 1.85, p = 0.08) and overall survival (OS) (HR = 3.82, p < 0.001). Patients with PNI < 49 were at a higher risk of IT failure (HR = 2.24, p = 0.0001) and subsequent death (HR = 2.84, p = 9 × 10^-5).

Conclusions: PNI can be a prognostic marker to predict response rates of patients with gynecologic cancers treated with immunotherapy. Additional studies needed to understand the mechanistic role of malnutrition in immunotherapy response.