The impact of the non-invasive follicular thyroid neoplasm with papillary-like nuclear feature terminology in the routine diagnosis of thyroid tumours.

BACKGROUND: Due to the recent proposal of the non-invasive follicular thyroid neoplasm with papillary-like nuclear feature (NIFTP) category, the authors analyse the state of the art in the challenging diagnosis of follicular thyroid neoplasms in routine practice. METHODS AND RESULTS: A consecutive series of 200 histological diagnoses, with complete cytological correlation, was analysed following the introduction of the NIFTP definition. The study was conducted in a general hospital with a high prevalence of thyroid benign nodules that accounted for approximately 60% of surgically-treated nodules. The significant incidence of the new NIFTP category was 7%. Concurrently, a gradual decrease of the follicular variant of papillary thyroid carcinoma (fvPTC) was observed (3.5%). When evaluating the FNA biopsies within the NIFTP group, despite the systematic evaluation of nuclear crowding, enlargement, irregularities and clearing, the final cytological class was often indeterminate for malignancy (Thy3/III-IV, 71%). At histology, the application of the semiquantitative NIFTP score for the evaluation of the PTC-like nuclear features was able to discriminate benign lesions (score 0/1) from fvPTC (score 2/3). A certain degree of overlapping still persisted between NIFTP and fvPTC (score 2) or between NIFTP and benign lesions (score 1). CONCLUSIONS: In the routine evaluation of FNA biopsies, the presence of subtle and questionable PTC-like nuclear features still remains a controversial aspect of the diagnostic workflow. Given that the NIFTP category was introduced to stratify the low-risk group of thyroid tumours more precisely, pathologists should force themselves to apply the nuclear score rigorously and to classify cases assigned a score of 1 as benign proliferations.

Grading the neuroendocrine tumors of the lung: an evidence-based proposal.

Lung neuroendocrine tumors are catalogued in four categories by the World Health Organization (WHO 2004) classification. Its reproducibility and prognostic efficacy was disputed. The WHO 2010 classification of digestive neuroendocrine neoplasms is based on Ki67 proliferation assessment and proved prognostically effective. This study aims at comparing these two classifications and at defining a prognostic grading system for lung neuroendocrine tumors. The study included 399 patients who underwent surgery and with at least 1 year follow-up between 1989 and 2011. Data on 21 variables were collected, and performance of grading systems and their components was compared by Cox regression and multivariable analyses. All statistical tests were two-sided. At Cox analysis, WHO 2004 stratified patients into three major groups with statistically significant survival difference (typical carcinoid vs atypical carcinoid (AC), P=0.021; AC vs large-cell/small-cell lung neuroendocrine carcinomas, P<0.001). Optimal discrimination in three groups was observed by Ki67% (Ki67% cutoffs: G1 <4, G2 4-<25, G3 ≥25; G1 vs G2, P=0.021; and G2 vs G3, P≤0.001), mitotic count (G1 ≤2, G2 >2-47, G3 >47; G1 vs G2, P≤0.001; and G2 vs G3, P≤0.001), and presence of necrosis (G1 absent, G2 <10% of sample, G3 >10% of sample; G1 vs G2, P≤0.001; and G2 vs G3, P≤0.001) at uni and multivariable analyses. The combination of these three variables resulted in a simple and effective grading system. A three-tiers grading system based on Ki67 index, mitotic count, and necrosis with cutoffs specifically generated for lung neuroendocrine tumors is prognostically effective and accurate.

A rare case of multiple congenital epulis.

We report a case in a female newborn infant of multiple congenital epulis, i.e. granular cell tumor, that was undetected during regular pregnancy ultrasound monitoring. At birth the neoplasms appeared as two voluminous lesions protruding from the newborn's mouth. The greater of them (5.5 cm x4 cm x3 cm) was pedunculated and attached to the external superior gingiva, shifting the alae nasi and making it difficult to enter the coanae. The second mass was somewhat smaller (3 cm x4 cm x2.5 cm), pedunculated and attached to the external inferior gum. A third smaller mass was less evident, unpedunculated and attached to the rim of the lower gingiva. Histologically the lesions were characterized by large cells, which had abundant pale acidophilic granular cytoplasm. A round-oval nucleus was located centrally. The cell membranes were distinct. Neither mitosis nor necrosis was found. Staining for cytoplasmic granules was intensely periodic acid-Schiff (PAS) positive and diastase resistant. Immunohistochemical negativity for S100 protein, positivity for lysozyme and numerous phagolysosomes in the cytoplasm of neoplastic elements, observed on ultrastructural examination, supported the hypothesis that the congenital type of granular cell tumor cannot have a Schwannian origin like that of the adult type, but is probably a mesenchymal lesion which, for unknown cause, regresses by a degenerative process.