Metastatic renal cell carcinoma to the thyroid gland 24 years after the primary tumour

Abstract

Among the metastases to thyroid gland, metastases from renal cell carcinoma (RCC) are not rare and their frequent macroscopic looks are similar to primary thyroid tumours. We report an unusual case of thyroid metastases from renal carcinoma in a 72 -year-old man presented with a 1-year history of choking spells, stridor and dyspnoea. Patient underwent right nephrectomy for RCC, 24 years ago. In the present case, a right hemithyroidectomy was performed for a suspected anaplastic thyroid carcinoma. Histological examination showed a metastases of a clear cell renal carcinoma. Although the RCC showed an indolent biological behaviour, the late thyroid metastases have concurred with a poor prognosis and the patient died 5 months after surgery. The interest of this case lies in the long progression-free survival of the RCC preceded by the diagnosis of the thyroid nodule and the discrepancy between the clinical-radiological and the histological assessment.

Figure 2

Grossly, the right lobe of thyroid showed a white-grayish solid, partially encapsulated mass (inset). Histologically, thyroid tumour showed a prevalent solid pattern: clear cells were evident (H&E ×10).

Figure 1

(A) Cell cluster formed by atypical epithelial cells with pleomorphic nuclei and prominent nucleoli. The background contains numerous polymorphous nuclear neutrophils and red blood cells (Papanicolau ×10). (B) A monolayer of cells with clear cytoplasms and well-defined cell borders (Papanicolau ×20).

Figure 3

(A) A pseudopapillary architecture resembling a primary thyroid tumour was present (H&E ×10). (B) Presence of erythrocytes in the centre of pseudogland simulated renal cell carcinoma (H&E ×20). (C) Tumour cells were positive for CD10 1 (immunoperoxidase ×20). (D) Tumour cells showed no reactivity with TTF-1 (immunoperoxi8dase ×40).