nasopharyngeal low-grade papillary adenocarcinoma

Definition: Thyroid-like low-grade nasopharyngeal papillary adenocarcinoma (TL-LGNPPA) is an extremely rare neoplasm characterized by morphological analogy to papillary thyroid carcinoma and abnormal expression of thyroid transcription factor-1 (TTF-1).

Histologically, the tumor consists of papillary growth of cuboidal or columnar epithelium. Tubular architecture and a spindle cell component were also observed focally. Some tumor cells exhibited intra-nuclear cytoplasmic inclusions.

Immunohistochemically, the neoplastic cells are positive for pancytokeratin (AE1/AE3), CK7, CK19, TTF-1, vimentin and HBME1, but negative for thyroglobulin, Pax8 and CK5/6.

Open references

 Low-grade papillary adenocarcinoma of nasopharynx with expression of thyroid transcription factor-1: Case report and review of literature.
Rajeswari B, Sukumaran Nair RK, Parukuttyamma K, Mathews A.
Indian J Pathol Microbiol. 2016 Oct-Dec;59(4):518-520. doi : 10.4103/0377-4929.191809
PMID: 27721286 Free

 Clinicopathological Features of Low-Grade Thyroid-like Nasopharyngeal Papillary Adenocarcinoma.
Li M, Wei J, Yao X, Wang C.
Cancer Res Treat. 2017 Jan;49(1):213-218. doi : 10.4143/crt.2016.195
PMID: 27384157 Free

Paywall References

 Thyroid-like low-grade nasopharyngeal papillary adenocarcinoma: Case report and literature review. Oishi N, Kondo T, Nakazawa T, Mochizuki K, Kasai K, Inoue T, Yamamoto T, Watanabe H, Hatsushika K, Masuyama K, Katoh R. Pathol Res Pract. 2014 May 9. pii: S0344-0338(14)00130-7. doi : 10.1016/j.prp.2014.04.02 PMID: 24893893

 Thyroid-like low-grade nasopharyngeal papillary adenocarcinoma: report of two cases. Ohe C, Sakaida N, Tadokoro C, Fukui H, Asako M, Tomoda K, Uemura Y.
Pathol Int. 2010 Feb;60(2):107-11. doi : 10.1111/j.1440-1827.2009.02480.x
PMID: 20398195