Thyroid-like low-grade nasopharyngeal papillary adenocarcinoma shows TTF-1 expression and Ki-67 less than 10% in reported cases

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Frontiers in Medicine Published June 2, 2026 Medically reviewed June 2, 2026 DOI ↗ By Dr. Julia Lee, PhD · Oncology, Genomics & Drug Development

Key Takeaway

Consider comprehensive histological, immunohistochemical, and imaging assessment for accurate diagnosis of TL-LGNPPA.

This case report with literature review focuses on thyroid-like low-grade nasopharyngeal papillary adenocarcinoma (TL-LGNPPA). The authors describe the typical histological features, which include papillary and ductal structures with a fibrovascular axis present in the interstitium. Nuclear features may occasionally show focal nuclear grooves, and a moderate degree of atypia is observed.

Immunohistochemical analysis reveals that all tumors expressed TTF-1 and CK, while TG was mostly negative. The Ki-67 proliferation index was generally less than 10% in most cases. These findings help distinguish this rare entity from other nasopharyngeal tumors.

The authors note that an accurate diagnosis requires a comprehensive consideration of histological morphological assessment, immunohistochemical analysis, and imaging examination. Specific sample size, setting, and follow-up duration were not reported. Safety data and adverse events were not reported. The practice relevance lies in the need for integrated diagnostic approaches to confirm this specific pathology.

Study Details

Study typeMeta analysis

EvidenceLevel 1

PublishedJun 2026

View Original Abstract ↓

ObjectiveThis paper aims to systematically investigate the clinical and pathological characteristics of TL-LGNPPA and its differential diagnosis, with the objective of enhancing our understanding of this tumor and facilitating the development of more precise treatment strategies.MethodsA systematic review and meta-analysis of the clinical and pathological features, as well as differential diagnosis, of a case of TL-LGNPPA were conducted, and a comprehensive literature review was conducted by analyzing relevant articles published on PubMed.ResultsThe histological features of TL-LGNPPA are typically characterized by typical papillary and ductal structures, with fibrovascular axis present in the interstitium. Focal nuclear grooves may occasionally be seen, with moderate degree of atypia. Immunohistochemical analysis showed that all tumors expressed TTF-1 and CK, but TG was mostly negative, and the Ki-67 proliferation index was generally less than 10% in most cases.ConclusionsTL-LGNPPA is a rare nasopharyngeal tumor with histological features similar to papillary thyroid carcinoma. An accurate diagnosis requires a comprehensive consideration of histological morphological assessment, immunohistochemical analysis and imaging examination.