Core Needle Biopsies in Patients With Lymphoproliferative Malignancies: An Observational Single-Center Cohort Study.

In the diagnostic evaluation of suspected lymphoma, both core needle biopsy (CNB) and surgical excisional biopsy (SEB) are routinely employed for tissue sampling. While SEB remains the gold standard, CNB is a less invasive and more cost-effective alternative. However, concerns persist regarding its diagnostic yield. This study aimed to assess the diagnostic performance of CNB in comparison to SEB in routine clinical practice. We included 179 patients with newly diagnosed lymphoma referred to Zealand University Hospital in 2023, of whom 84 underwent CNB based on PET/CT findings. A definitive lymphoma diagnosis was established in 74% of CNB cases, compared to 98% with SEB, underscoring a lower diagnostic yield of CNB. The diagnostic accuracy of CNB varied by biopsy location, lymphoma subtype, and the volume of tissue obtained. Inconclusive diagnoses were more frequent in indolent lymphoma subtypes, biopsies yielding a limited number of tissue cylinders, and samples taken from the axillary and inguinal regions or extranodal sites. Grade 3-4 complications were observed in 1% of CNBs and in 5% of SEBs. Although CNB was a safe procedure, further refinement of biopsy techniques and improved patient selection are needed to enhance its diagnostic accuracy and clinical utility.