Non-functioning parathyroid carcinoma: a case report

Nobuyasu Suganuma,Satoru Shimizu,Yasushi Rino,Izumi Kojima,Kae Kawachi,Hiroyuki Iwasaki,Akio Miyake,Takashi Yamanaka,Hirotaka Nakayama,Yohei Miyagi,Soji Toda,Haruhiko Yamazaki,Katsuhiko Masudo,Tatsuya Yoshida,Kenichi Ohashi,Munetaka Masuda

doi:10.1186/s40792-017-0357-4

Abstract

BackgroundNon-functioning parathyroid carcinoma is a rare disease that is difficult to distinguish from other diseases based on the lack of hyperparathyroidism. This is a report of non-functioning parathyroid carcinoma diagnosed by reverse transcription polymerase chain reaction (RT-PCR) targeting parathyroid hormone (PTH) messenger RNA.Case PresentationThe patient is a 67-year-old male who visited our hospital for the chief complaint of hoarseness. A 5-cm mass was observed in the right lobe of the thyroid gland, and poorly differentiated thyroid carcinoma was suspected according to the fine-needle biopsy results. The laboratory data for thyroid functions, thyroglobulin, anti-thyroglobulin antibodies, calcium, phosphorus, and intact-PTH were all within the normal range. Right recurrent nerve paralysis was observed preoperatively. The patient was diagnosed with poorly differentiated thyroid carcinoma, and total thyroidectomy and central node dissection with partial resection of the right recurrent nerve and esophageal muscle were performed. The pathological findings revealed atypical cells containing clear cells in solid and alveolar structures with broad fibrosis. Mitosis, focal coagulative necrosis, and vascular and capsular invasions were observed. A slightly positive PTH immunohistochemical stain was noted, whereas the RT-PCR results were positive. We finally diagnosed this tumor as non-functioning PTC. No distant metastasis occurred, and the patient is still alive.ConclusionsThis is a report of a patient with non-functioning parathyroid carcinoma, which is clinically very rare. We diagnosed this tumor as non-functioning parathyroid carcinoma using RT-PCR for PTH mRNA.

Highlights

Non-functioning parathyroid carcinoma is a rare disease that is difficult to distinguish from other diseases based on the lack of hyperparathyroidism
This is a report of a patient with non-functioning parathyroid carcinoma, which is clinically very rare
We diagnosed this tumor as non-functioning parathyroid carcinoma using reverse transcription polymerase chain reaction (RT-PCR) for parathyroid hormone (PTH) messenger RNA (mRNA)

Summary

Background

Parathyroid carcinoma (PTC) is a rare type of endocrine tumor that accounts for less than 5% of all cases of primary hyperparathyroidism. The tumor involved a right recurrent nerve and invaded the sternothyroid muscle on the ventral side and the muscular layer of esophagus and the membranous wall of trachea on the dorsal side. Some parts of the right recurrent nerve, the muscular layer of the esophagus, and the membranous wall of tracheal were resected with the tumor via thyroidectomy along with lymph nodes of the central compartment. The tumor was a solid gray white mass of 42 × 37 × 28 mm with an irregular surface invading the sternothyroid muscle, right recurrent nerve, the muscular layer of esophagus, and the membranous wall of trachea. PTH mRNA expression was observed, and we diagnosed this tumor as non-functioning PTC (Fig. 6). No distal metastasis has occurred, and the patient is still alive

Findings

Discussion

Conclusions