The Role of Laparoscopy in Diffuse Large B-Cell Lymphoma with High 18F-Fluorodeoxyglucose Uptake Lymph Node in the Retroperitoneum After Chemotherapy.

BACKGROUND In the management of diffuse large B-cell lymphoma (DLBCL), PET/CT imaging is routinely utilized after completion of 6-8 cycles of chemotherapy to assess therapeutic response. Lymph nodes displaying elevated 18F-Fluorodeoxyglucose (FDG) uptake on these scans frequently necessitate pathological verification or escalation of treatment intensity. While core-needle biopsy (CNB) is a widely used minimally invasive technique for lymph node sampling in superficial anatomical sites, its diagnostic yield for retroperitoneal lymph nodes remains suboptimal due to technical constraints, necessitating reliable diagnostic alternatives. Presently, standardized diagnostic algorithms are lacking for such metabolically active retroperitoneal lesions. CASE REPORT We prospectively evaluated 5 consecutive DLBCL patients with histologically confirmed diagnoses who completed 6-8 cycles of first-line immunochemotherapy. End-of-treatment PET/CT demonstrated metabolically active retroperitoneal lymph nodes (Deauville score 4-5) in all participants, meeting the criteria for equivocal treatment response. After excluding surgical contraindications, diagnostic laparoscopic retroperitoneal lymph node excision was performed under general anesthesia. The procedure successfully retrieved adequate tissue specimens from all targeted lesions, without intraoperative complications. Systematic histopathological evaluation incorporating immunohistochemical staining protocols was subsequently conducted on all specimens, revealing benign changes in 4 cases and residual lymphoma in 1 case. The resultant pathological profiles provided critical diagnostic clarity, directly informing subsequent therapeutic decision-making for each patient. CONCLUSIONS Laparoscopic lymph node excision constitutes a technically feasible and diagnostically robust approach for DLBCL patients with post-chemotherapy retroperitoneal FDG-avid lesions. This technique offers superior tissue acquisition capability compared to percutaneous biopsies, delivering essential pathological evidence to guide risk-adapted management strategies when conventional diagnostic modalities prove inconclusive.