Abstract 4205: Profiling symptom burden of RAS and BRAF mutations in patients with colorectal cancer: Results from the ColoCare Study
Authors: Rouhani Gazelle , Bloomer Amanda M. , Gomez Maria F. , Trujillo Gillian K. , Conant Devon N. , Felder Seth I. , Ulrich Cornelia M. , Li Christopher I. , Figueiredo Jane C. , Toriola Adetunji T. , Gigic Biljana , Schneider Martin , Shibata David , Siegel Erin M. 
Published: April 2023

Background: Colorectal cancer (CRC) is a complex and heterogeneous disease characterized by distinct molecular features such as RAS and BRAF mutations. Assessing these molecular aberrations provides clinical guidance for selecting and predicting response with therapeutic modalities. Few reports have suggested that patient symptom burden at diagnosis differs across molecular subtypes of CRC. However, the association of RAS and BRAF mutations and symptom burden post-diagnosis in CRC patients has yet to be examined in a prospective cohort.

Methods: We assessed CRC patients, stage I-IV, enrolled in the Moffitt ColoCare Study site with clinical molecular testing results and who completed a six-month questionnaire. Tumor mutation (MT) status (RAS/BRAF/Wildtype (WT)) was abstracted from the medical record. The MD Anderson Symptom Inventory (MDASI) was used to assess the severity of 13 cancer-related symptoms on a 1-to-10 scale. Mean scores in mutation subgroups were compared with one-way ANOVA. Linear regression analysis evaluated the association between symptom burden and mutation status. Multivariable regression models were adjusted for age, sex, stage at diagnosis, treatment, and microsatellite instability (MSI).

Results: Among the 158 patients, the mean age at diagnosis was 60.9 ± 11.58 years. The prevalence of RAS and BRAF mutations was 30.4% (N=48) and 6.3% (N=10), respectively. Statistically significant mean differences between the mutation subgroups were distress (p=0.005), difficulty remembering (p=0.015), lack of appetite (p=0.042), and sadness (p=0.007). Patients with a BRAF-MT reported significantly more distress (p=0.001), difficulty remembering (p=0.029), and sadness (p=0.002) at six months compared to RAS-MT or RAS/BRAF-WT. Patients with a RAS-MT reported an increased lack of appetite (p=0.038) compared to BRAF-MT or RAS/BRAF-WT. Patients with a BRAF-MT reported higher severity of symptoms interfering with the enjoyment of life (p&lt;0.001), work (p=0.005), and mood (p&lt;0.001) compared to RAS-MT or RAS/BRAF-WT. In an adjusted multivariable model, patients with BRAF-MT tumors reported significantly greater distress compared with RAS/BRAF-WT patients [β = 3.18 per unit increase in severity, 95% CI (1.30 - 5.07), p=0.001)]. Overall symptom burden was associated with greater interference with daily activities for BRAF-MT patients when compared to RAS/BRAF-WT patients [β = 2.95, 95% CI (1.42 - 4.48), p&lt;0.001)].

Conclusions: Tumors with BRAF-MT are molecularly classified into the serrated pathway, which has distinct clinical characteristics and risk factor profile. In this study, patients with tumors harboring BRAF-MT reported a higher symptom burden six months post-diagnosis than those with RAS-MT or RAS/BRAF-WT tumors. While the prevalence of BRAF-MT was low in this population, these findings warrant further investigation in a larger cohort.

Citation Format: Gazelle Rouhani, Amanda M. Bloomer, Maria F. Gomez, Gillian K. Trujillo, Devon N. Conant, Seth I. Felder, Cornelia M. Ulrich, Christopher I. Li, Jane C. Figueiredo, Adetunji T. Toriola, Biljana Gigic, Martin Schneider, David Shibata, Erin M. Siegel. Profiling symptom burden of RAS and BRAF mutations in patients with colorectal cancer: Results from the ColoCare Study. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4205.