Papillary thyroid carcinoma with aggressive fused follicular and solid growth pattern: A unique histological subtype with high-grade malignancy?
Pathol Int
; 73(5): 207-211, 2023 May.
Article
em En
| MEDLINE
| ID: mdl-37042564
ABSTRACT
Papillary thyroid carcinoma (PTC) is usually indolent; however, some rare subtypes of PTCs, such as columnar cell and hobnail subtypes, carry poor prognosis as an intermediate malignancy between differentiated carcinoma and anaplastic carcinoma. We present the case of a 56-year-old Japanese woman having PTC with aggressive behavior showing characteristic histological features of a predominantly fused follicular and focally solid (FFS) pattern. The fused follicular pattern is cribriform-like without intermingled vessels. This PTC with FFS pattern included frequent mitotic figures, necrosis, lymphovascular invasion, and metastases with high clinical stage. The tumor cells were broadly positive for antibodies to TTF-1, PAX8, and bcl-2, and negative for cyclin D1. Ki-67 labeling index was approximately 10%, and there was occasional positivity of p53. Targeted next generation sequencing analysis only detected a NRAS mutation (Q61K); there was no mutation and no translocation of other genes including BRAF and RET/PTC. To our knowledge, this is first report that PTC shows aggressive FFS growth pattern. The tumor is possibly included in the new category of differentiated high-grade thyroid carcinoma in the World Health Organization 2022 classification, or in a novel subtype of PTC owing to its characteristic histological feature and intermediate malignancy between differentiated carcinoma and anaplastic carcinoma.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Contexto em Saúde:
2_ODS3
Base de dados:
MEDLINE
Assunto principal:
Neoplasias da Glândula Tireoide
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Carcinoma
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Carcinoma Papilar
/
Adenocarcinoma
Tipo de estudo:
Prognostic_studies
Limite:
Female
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Humans
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Middle aged
Idioma:
En
Revista:
Pathol Int
Ano de publicação:
2023
Tipo de documento:
Article