Diagnostic FNA biopsies of palpable lesions without ultrasound guidance: a single-center study and narrative review of the literature

Abstract

Introduction

Recent studies suggest that ultrasound-guided fine-needle aspiration biopsy (iFNAb) enhances diagnostic accuracy for palpable lesions. This study evaluates the efficacy of palpation-guided FNAb (pFNAb) performed at Unidade Local de Saúde de Coimbra, Portugal, compares findings to existing literature, and identifies lesions that could benefit from ultrasound guidance.

Materials and methods

A retrospective review of 278 pFNAb cases from 2021 to 2023 was conducted, collecting data on lesion characteristics, procedural details, and operator expertise. Diagnostic accuracy was determined through concordance with histopathology, flow cytometry, or clinical follow-up. Statistical analyses included Fisher’s exact test, chi-square tests, and logistic regression. A Preferred Reporting Items for Systematic reviews and Meta-Analyses-guided literature review was also performed to contextualize findings.

Results

Diagnostic accuracy was achieved in 84% of pFNAb cases. Lesions less than 1 cm exhibited significantly lower diagnostic rates compared to larger lesions. Diagnostic accuracy improved with additional needle passes, reaching 87% with 3 attempts. Anatomical location significantly influenced outcomes, with scalp lesions having the lowest diagnostic rate (33%) compared to skin and soft tissue lesions (85.7%). Literature review findings corroborated the data, emphasizing the superior accuracy of iFNAb for smaller or anatomically challenging lesions.

Conclusions

pFNAb is effective for diagnosing most palpable lesions and provides a standard of care in settings without imaging resources. However, iFNAb is recommended for specific cases, such as small or scalp lesions, to enhance diagnostic accuracy. Tailoring biopsy approaches based on lesion characteristics can improve outcomes, reduce repeat procedures, and enhance patient care.