Background: Nutritional status is a recognized determinant of treatment tolerance and clinical outcomes in oncology. This study aimed to assess body composition using computed tomography (CT) and to evaluate its association with progression-free survival (PFS) and overall survival (OS) in patients with locally advanced rectal cancer (LARC) undergoing curative multimodal therapy. Methods: A total of 216 patients with LARC who underwent neoadjuvant chemoradiotherapy (CRT) were retrospectively assessed. Two radiochemotherapy protocols were used: long-course chemoradiotherapy (lcCRT) (radiation therapy administered daily at doses of 1.8 or 2.0 Gy, for a total dose of 50.4–55.8 Gy) with concurrent chemotherapy: either 5-FU with leucovorin or capecitabine and total neoadjuvant chemoradiotherapy (tnCRT)—short-course radiotherapy (5 × 5 Gy) followed by sequential chemotherapy with CAPOX or FOLFOX. Surgery was performed 6.5 weeks after completing CRT. Radiotherapy was delivered using linear accelerators based on the Intensity-Modulated Radiation Therapy technique. CT scans were used to assess nutritional status. Survival analyses were performed. Data on food consumption frequency were collected using the Dietary Habits and Nutrition Beliefs Questionnaire (KomPAN^®). Non-Healthy-Diet-Index-14 (nHDI-14) was calculated. Results: Median observation time was 58 months (range 4–118 months). VATI level and OS (HR: 0.4618 95% CI: 0.2194–0.9719, p = 0.0419), as well as SATI and OS (HR: 0.4707 95% CI: 0.2286–0.9693, p = 0.0409) were significantly associated. This association was not significant for PFS (VATI: HR: 0.7084 95% CI: 0.4055–1.2376, p = 0.2259; SATI: HR: 0.6864 95% CI: 0.3932–1.1981, p = 0.1855). SMI and PMI values were not significantly related either PFS (SMI-HR: 0.6728, 95% CI: 0.4031–1.1231, p = 0.1295; PMI-HR: 0.7385, 95% CI: 0.4628–1.1785, p = 0.2036) or OS (SMI-HR: 0.9128, 95% CI: 0.4703–1.7720, p = 0.7876; PMI-HR: 0.6592 95% CI: 0.3684–1.1794, p = 0.1603). No significant association was found between sarcopenia development and PFS (HR: 1.2733 CI: 0.7589–2.1363; p = 0.3602) or OS (HR: 1.1207; CI: 0.5681–2.2107; p = 0.7424). Significant differences between men and women in alcohol intake and nHDI-14 were observed. Conclusions: Low visceral and subcutaneous adipose tissue index were significantly associated with worse OS in patients with LARC undergoing multimodal treatment. The nHDI-14 was negatively correlated with the duration of observation and patients’ age.

Anti-EGFR antibodies combined with chemotherapy doublets are a cornerstone of the upfront treatment of colorectal cancer. RAS and BRAF mutations are established negative predictive factors for such therapy. The primary tumour located in the proximal colon has recently emerged as another negative predictive factor. We have conducted a retrospective multicentre study to collect data on real-world population characteristics, practice patterns, and outcomes in patients with metastatic colorectal cancer treated in a first-line setting with either cetuximab or panitumumab in combination with either FOLFOX or FOLFIRI chemotherapy. The presented analysis focuses on the impact of the primary tumour location. 126 of 842 patients analysed (15.0%) had proximal primary. It was associated with a lower BMI at diagnosis, mucinous histology, and peritoneal metastases. It was also associated with inferior treatment outcomes in terms of response ratio: 59.4% vs. 74.22% (odds ratio [OR] 0.51, 95% CI 0.33–0.78, p = 0.010), and median depth of response: −36.7% vs. −50.0% (p = 0.038). There was only a borderline non-significant trend for inferior PFS in patients with proximal tumours. OS data was incomplete. The presented analysis confirms the negative impact of tumour sidedness on the efficacy of an upfront anti-EGFR-chemotherapy combination and provides valuable data on real-world population characteristics.