Analysis of Biopsy Modalities and Timeline for the Workup of Undiagnosed Lesions: Mayo Clinic Experience.

Abstract

Objective: Incidental lesions identified clinically or on imaging are diagnostically challenging. The workup for these lesions is not well established. We investigated diagnostic modalities used at our institutions for undiagnosed lesions and the timeline from intake to biopsy and resultant diagnoses.

Methods: We retrospectively analyzed data from all 3 Mayo Clinic sites (Arizona, Florida, and Minnesota) between November 1, 2018 and July 31, 2022. We evaluated the frequency of the biopsy technique used (if any) and how often the resultant diagnosis was malignant, benign, or inconclusive. The turnaround time from intake to biopsy and final diagnosis also was evaluated.

Results: Of 93 patients with an undiagnosed lesion, 54 (58%) underwent biopsy; most patients underwent a single biopsy (n = 42, 77%), and 12 (23%) had two or more biopsies. Unbiopsied patients were diagnosed as having benign lesions according to imaging or had follow-up imaging. Of the 54 patients biopsied, 38 (70%) biopsies were obtained via fine-needle aspiration. Biopsy results were malignant for 34 patients (63%), benign for 14 (26%), and inconclusive for six (11%). Most patients were seen within 9 days of their initial contact (69/93, 74%), underwent biopsy within 20 days of seeing the physician (40/54, 74%), and had a final diagnosis within 30 days of the initial visit (72/93, 77%).

Conclusions: Our findings can help clinicians dispel the misconception that most undiagnosed lesions are malignant. Our findings also may help clinicians determine the appropriate workup for undiagnosed lesions. Further research is recommended to guide clinicians on the best sampling methodologies to obtain the highest yield of tissue for analysis. Dedicated patient workflows can help expedite diagnosis.