Radiation Oncology Journal · 2 authors, 2 centres
This summary was generated by AI from a single paper. It has not been reviewed by a clinician and is not clinical advice. Verify against the source before acting on it.
This retrospective study of 50 patients with esophageal squamous cell carcinoma found that a low baseline BMI (<18.5 kg/m²) was associated with worse progression-free survival and overall survival following radiotherapy. Underweight patients more frequently had advanced T-stage disease and experienced more treatment interruptions. The findings suggest clinicians should closely monitor BMI in esophageal SCC patients undergoing curative radiotherapy.
**Background:** Weight loss and low body mass index (BMI) have been associated with poor prognosis in various cancers, particularly gastrointestinal malignancies. Previous studies have shown conflicting results regarding the relationship between BMI and outcomes in esophageal cancer. This study aimed to evaluate whether baseline BMI is associated with treatment outcomes in patients with esophageal squamous cell carcinoma (SCC) receiving curative radiotherapy (RT), and to assess relationships between BMI and clinical factors such as T stage, N stage, and comorbidities.
**Methods:** The authors retrospectively analyzed data from 50 patients with esophageal SCC who underwent curative RT as first-line treatment at Inje University Busan Paik Hospital from December 2009 to January 2022. All patients were pathologically diagnosed with SCC and had no distant metastases. Patients receiving less than 40 Gy cumulative RT dose were excluded. BMI was calculated from medical records and categorized as underweight (<18.5 kg/m²), normal weight (18.5–24.9 kg/m²), or overweight (>25 kg/m²). Most patients (96%) received concurrent chemoradiotherapy, primarily with 5-fluorouracil and cisplatin. The primary outcome was progression-free survival (PFS); secondary outcomes were overall survival (OS) and locoregional PFS (LRPFS). Statistical methods included chi-squared tests, Fisher exact tests, Kaplan–Meier survival analysis, log-rank tests, and Cox regression proportional hazards models.
**Key Results:** The median follow-up was 9 months (range 1.5–85.7 months). Patient characteristics: median age 68 years (range 46–83); T stage distribution: T1 (7 patients, 14%), T2 (18, 36%), T3 (19, 38%), T4 (6, 12%); 30 patients (60%) had nodal metastases at diagnosis. Based on BMI, 7 patients (14%) were underweight, 27 (54%) normal weight, and 16 (32%) overweight. Six patients (12%) had type 2 diabetes. The 3-year PFS and OS rates were 26.3% and 69.2%, respectively. The 3-year LRPFS rate was 36.6%. During follow-up, 29 patients experienced disease progression; 21 (42%) had locoregional failure and 11 (22%) had distant failure. Univariate analysis showed that being underweight was significantly associated with worse PFS (p = 0.011) and worse OS (p = 0.004). Positive N stage was also associated with worse PFS (p = 0.017). Total radiation dose <50 Gy was associated with worse OS (p = 0.001). Being underweight was significantly associated with impaired LRPFS (p = 0.004). Low BMI was more common in patients with advanced T stage (T3/T4): 7 out of 43 patients with T3/T4 disease were underweight (p = 0.010). Treatment interruption (total RT period >50 days) occurred more frequently in underweight patients (4/7 vs. 7/43, p = 0.034). However, in multivariate analysis, being underweight was not an independent prognostic factor for PFS or OS. N stage was an independent prognostic factor for PFS, and total radiation dose was an independent prognostic factor for OS.
**Clinical Implications:** This study confirms that low pre-treatment BMI is associated with poorer survival outcomes in esophageal SCC patients undergoing curative RT, though it was not an independent prognostic factor, possibly due to the small sample size. The association between low BMI and advanced T stage suggests that tumor burden may contribute to weight loss. The higher rate of treatment interruptions in underweight patients highlights the need for nutritional support during RT. The authors recommend that clinicians pay special attention to underweight patients and consider early nutritional interventions, including possible stent insertion or feeding gastrostomy, though further studies are needed to determine whether such interventions improve outcomes. Study limitations include the small sample size, single-center retrospective design, lack of continuous weight monitoring, and the inability to demonstrate BMI as an independent prognostic factor in multivariate analysis.