Intermixed medullary and papillary thyroid cancer in a patient with renal cell carcinoma

Abstract

Summary We report a rare case of concurrent medullary thyroid cancer (MTC) and papillary thyroid cancer (PTC) with intermixed disease in several of the lymph node (LN) metastases in a patient who was subsequently diagnosed with clear cell renal cell carcinoma (RCC). A 56 year old female presented with dysphagia and was found to have a left thyroid nodule and left superior cervical LN with suspicious sonographic features. Fine needle aspiration biopsy (FNAB) demonstrated PTC in the left thyroid nodule and MTC in the left cervical LN. Histopathology demonstrated multifocal PTC with 3/21 LNs positive for metastatic PTC. One LN in the left lateral neck dissection exhibited features of both MTC and PTC within the same node. In the right lobe, a 0.3 cm focus of MTC with extra-thyroidal extension was noted. Given persistent calcitonin elevation, a follow-up ultrasound displayed an abnormal left level 4 LN. FNAB showed features of both PTC and MTC on the cytopathology itself. The patient underwent repeat central and left radical neck dissection with 3/6 LNs positive for PTC in the central neck and 2/6 LNs positive for intermixed PTC and MTC in the left neck. There was no evidence of distant metastases on computed tomography and whole body scintigraphy, however a 1.9 x 2.5 cm enhancing mass within the right inter-polar kidney was discovered. This lesion was highly suspicious for RCC. Surgical pathology revealed a 2.5 cm clear cell RCC, Fuhrman grade 2/4, with negative surgical margins. She continues to be observed with stable imaging of her triple malignancies. Learning points: Mixed medullary-papillary thyroid neoplasm is characterized by the presence of morphological and immunohistochemical features of both medullary and papillary thyroid cancers within the same lesion. Simultaneous occurrence of these carcinomas has been previously reported, but a mixed disease within the same lymph node is an infrequent phenomenon. Prognosis of mixed medullary-papillary thyroid carcinomas is determined by the medullary component. Therefore, when PTC and MTC occur concurrently, the priority should be given to the management of MTC, which involves total thyroidectomy and central lymph node dissection. Patients with thyroid cancer, predominantly PTC, have shown higher than expected rates of RCC. To our knowledge, this is the first report describing the combination of MTC, PTC, and RCC in a single patient.

Thyroid and renal cancers: A bidirectional association

“…With regards to histology, the papillary phenotype of TC was found in all patients. Sporadic cases of follicular carcinoma (29) and medullary (32) thyroid carcinoma have also been identified; however, both of them were also associated with a papillary thyroid carcinoma. On the contrary, with regards to renal carcinoma, a greater variety was observed concerning histology.…”

Synchronous papillary-medullary thyroid microcarcinoma: a case report

“…Diagnosis is most often made by morphological examination, standard immunohistochemistry studies, and molecular detection based on the biopsy sample. Other diagnostic hints indicating this disease include elevated laboratory values of thyroglobulin, calcitonin, and carcinoembryonic antigen ( 4 , 5 , 9 , 10 , 14 , 17 , 31 ).…”

“…The medullary component is the main prognostic factor in cases of synchronous papillary-medullary thyroid malignancy, and the extent of surgical resection depends on the stage of the tumor ( 4 , 5 , 7 , 10 , 32 ). Although radioactive iodine ablation and thyroid-stimulating hormone (TSH) suppression is not useful in treatment of lone medullary thyroid carcinoma due to lack of accumulation of radioiodine in parafollicular C-cells, it may be useful for the treatment of the co-occurring papillary carcinoma ( 1 , 33 ).…”

Mixed medullary—papillary thyroid carcinoma with mixed lymph node metastases: A case report

“…3 The cell origin, histopathologic features, and prognosis of these tumors are different, and it is very rare to come across the simultaneous occurrence of these tumors. [4][5][6][7][8][9][10] Indeed, both type of carcinoma can occur in the same patient as a collision tumor, or as a mixed medullary-follicular thyroid carcinoma (MMFTC) (a real mixed tumor, with the immunoreactivity and morphological features of both types of carcinoma). 11 We present a case report of this rare association and provide a short review of the literature of this rare condition.…”

“…In contrast, MTC is an uncommon malignant epithelial neoplasm (5%‐10% of all thyroid cancers 2 ), which originates from the parafollicular C cell and is traditionally assumed to evolve from the ultimobranchial body of the neural crest 3 . The cell origin, histopathologic features, and prognosis of these tumors are different, and it is very rare to come across the simultaneous occurrence of these tumors 4‐10 . Indeed, both type of carcinoma can occur in the same patient as a collision tumor, or as a mixed medullary‐follicular thyroid carcinoma (MMFTC) (a real mixed tumor, with the immunoreactivity and morphological features of both types of carcinoma) 11 …”