2169 - Small Cell Lung Cancer Patients with Supraclavicular or Cervical Lymph Node Metastasis should be Treated with Limited-Stage Treatment Regimen

Y. Wang¹, J. Xie¹, P. Wu¹, R. Gao¹, X. Li², L. Jiang¹, X. WANG¹, Z. Huang³, J. Yu¹, and X. Meng¹; ¹Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China, ²Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China, ³Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China

Purpose/Objective(s): Historically, the treatment options for small cell lung cancer (SCLC) patients with supraclavicular (SCLN) and/or cervical lymph node (CLN) metastasis have been a topic of controversy. The purpose of this study is to discuss the treatment regimen in this population. Materials/

Methods: Between January 2016 to December 2021, SCLC patients with SCLN and/or CLN metastasis across two tertiary medical centers were enrolled. Propensity score matching (PSM) with a 2:1 ratio was performed. The primary endpoints were progression-free survival (PFS) and overall survival (OS).
Results: A total of 209 SCLC patients with SCLN and/or CLN metastasis were enrolled. After PSM, 156 patients were included, with 104 receiving radiotherapy (RT) and 52 receiving non-RT. Patients who received RT achieved longer median PFS (mPFS) (11.1 months vs. 5.7 months; HR 0.39, p < 0.001) and median OS (mOS) (27.0 months vs. 14.1 months, HR 0.35, p < 0.001) compared to those without RT after matching. Patients who received RT before 4 cycles of chemotherapy had better mPFS (11.6 months vs. 9.6 months, HR 1.59, p = 0.039) than those who received RT after 4 cycles. The predominant grade = 3 adverse events observed was leukopenia (affecting 51 [49.0%] of 104 patients in the RT group vs. 12 [23.1%] of 52 in the non-RT group). Grade =3 pneumonitis and oesophagitis were reported in 4.8% and 8.7% of patients, respectively.
Conclusion: RT could enhance survival for SCLC patients with SCLN and/or CLN metastasis, while maintaining a manageable safety profile. Individualized earlier implementation of RT based on the specifics of the lesion will prolong survival. These patients could be managed as limited-stage SCLC (LS-SCLC) rather than extensive-stage SCLC (ES-SCLC) with advancements in RT.