Subcutaneous fat necrosis of the newborn is a rare, transient panniculitis of full-term infants. Diagnosis is usually made clinically; however, a biopsy is sometimes required. Fine-needle aspiration biopsy (FNAB) offers an alternative to biopsy. The cytology shows a spectrum of changes ranging from clumped lobules of fat with opaque cytoplasm to necrotic aspirates with dispersed fat cells with opaque cytoplasm, foamy macrophages, multinucleated giant cells, lymphocytes, and neutrophils. Radially orientated, refractile, needle-shaped crystals are visible in the cytoplasm of the fat cells and loose lying in the necrotic background. FNAB offers an alternative to biopsy with good results.

Fine-needle aspiration biopsy (FNAB) has been widely accepted as a reliable diagnostic modality in the general pediatric population, but its role in pediatric oncology still remains elusive. With new treatment protocols subscribing to preoperative chemotherapy, the need for a quick, minimally invasive, and accurate diagnostic procedure has arisen. This study assesses the feasibility of FNAB in childhood malignancies to render a specific diagnosis on which treatment can be initiated. An 11-year retrospective study was done on FNABs in patients 19 years and under referred for clinically malignant mass lesions. Cases were confirmed with histology, immunocytochemistry, flow cytometry, or clinical follow-up. Of the 357 patients referred for FNABs, 36 patients were lost to follow-up and 31 FNABS were inadequate. A total of 290 cases were included in the study, of which 68 (23%) cases were benign and 222 (77%) were malignant. The most frequently occurring tumors were nephroblastoma (68), non-Hodgkin's lymphoma (39), rhabdomyosarcoma (22), Hodgkin's lymphoma (22), and neuroblastoma (22). The sensitivity of the procedure for neoplasia was 96.6%, the specificity 97.0%, positive predictive value 99.0%, and negative predictive value 90.1%, with a diagnostic accuracy of 96.7%. The ability of FNAB to enable a specific diagnosis to be made, that is correct and accurate subtyping of the tumor on which chemotherapy or radiotherapy could be commenced was 75.7%. This study shows that FNAB can be used with confidence to confirm malignancy in children. With clinicoradiological correlation and the aid of ancillary techniques, FNAB allows a rapid and accurate preoperative diagnosis for definitive therapy commencement in most cases.

<b><i>Objective:</i></b> This study aims to determine the diagnostic utility of the International Academy of Cytology (IAC) Yokohama System for reporting breast cytopathology in lesions of the male breast. <b><i>Study Design:</i></b> Fine-needle aspiration biopsy (FNAB) reports between 2015 and 2019 were retrospectively recategorized according to the 5-tiered IAC Yokohama Reporting System. Our database yielded a total of 1,532 FNAB reports from breast lesions, obtained from 1,350 male patients. The risk of malignancy (ROM) and diagnostic performance of FNAB were determined using follow-up histopathological diagnosis and/or clinical follow-up, where available, for each category. <b><i>Results:</i></b> The category distribution were as follows: inadequate, 40%; benign, 57%; atypical, 0.6%; suspicious for malignancy, 0.7%; and malignant, 1.6%. The ROM in each category was nondiagnostic, 11%; benign, 3%; atypical, 28%; suspicious for malignancy, 56%; and malignant, 100%. The sensitivity, specificity, positive predictive value, and negative predictive value were recorded as 63, 100, 100, and 84.6% respectively, when only malignant cases were considered as positive tests. <b><i>Conclusion:</i></b> This study validates the IAC Yokohama System for reporting male breast cytopathology. In accordance with the aim of the Yokohama System to establish best practice guidelines for reporting breast cytopathology, this comprehensive scheme facilitates comparisons between local and international institutions. The ROM acts as an internal audit for quality assurance within one’s own laboratory and provides guidance for clinical management. It highlights inefficiencies such as high inadequacy rates for category 1 and also features strengths with impressive specificity for categories 4 and 5.