Transrectal biplane ultrasound-guided transperineal biopsy for rectal and peri-rectal lesions: an 18-year retrospective analysis.

Background: Accurate diagnosis of rectal and perirectal lesions remains challenging, particularly for submucosal, necrotic, or anatomically complex masses where conventional endoscopic forceps biopsy (EFB) often yields insufficient tissue. Transrectal biplane ultrasound-guided transperineal biopsy (TRUSTPB) offers a potential alternative, but its diagnostic performance and safety in this setting require systematic evaluation. Methods: We conducted an 18-year retrospective study of 99 patients with rectal or perirectal lesions who underwent TRUSTPB at Zhejiang Cancer Hospital between 2006 and 2020. Technical success, diagnostic accuracy, sensitivity, and complication rates were assessed using final pathological diagnoses and long-term follow-up data. Diagnostic outcomes of TRUSTPB were compared with those of EFB. Associations between clinical variables (e.g., needle type, lesion size) and diagnostic yield were analyzed using Chi-squared tests and binary logistic regression. Results: TRUSTPB achieved a technical success rate of 96.0% (95/99). It demonstrated high diagnostic accuracy (91.9%) and sensitivity (95.1%) for malignancy, with no false-positive cases. In contrast, EFB showed significantly lower detection rates, especially in submucosal or necrotic lesions. Core needle biopsy was associated with higher diagnostic yield than fine-needle aspiration (P<0.05), particularly for lesions >25 mm. All four failed biopsies involved small or complex lesions sampled with fine needles, yielding only acellular or necrotic material. No major complications occurred. Conclusions: TRUSTPB is a safe, real-time, and highly accurate technique for diagnosing rectal and perirectal lesions, outperforming conventional EFB in challenging cases. It represents a preferred approach for lesions inaccessible or nondiagnostic by standard colonoscopy.