Primary follicular thyroid carcinoma metastasis to the kidney and widespread dissemination: A case report

Abstract

Distant metastases are more common in follicular thyroid carcinoma (FC) than in papillary thyroid carcinoma. However, FC metastasis to the kidney with eggshell calcification, as observed in the present case, is rare. The current report presents a case of a 67-year-old woman exhibiting a solitary tumor in the mid pole of the left kidney. Radical nephrectomy was performed, as the tumor was diagnosed as a primary renal carcinoma using contrast-enhanced computed tomography. Once the tumor was confirmed to be FC, total thyroidectomy was performed. Following administration of an oral therapeutic dose of 100 mCi 131I, functional imaging demonstrated the presence of multifocal metastases in the chest and abdomen. Euthyrox® was prescribed orally to aid normal thyroid function. Follow-up 6 months later using radionuclide imaging demonstrated the disappearance of the multifocal metastases in the chest and abdomen. The distant metastasis of FC may represent the initial symptom of the primary lesion, which was neglected. Ultrasound is an effective method to examine nodules located on the thyroid.

The Benefit of Primary Tumor Surgical Resection in Distant Metastatic Carcinomas of the Thyroid

“…Follicular thyroid carcinoma is the second most common histology; between 6% and 20% of diagnosed cases are reported to lead to distant metastasis (DM) 17–20 . Unique to the follicular variant is its propensity for hematological dissemination 21 . Medullary and anaplastic thyroid cancers, though rare, are associated with higher rates of DM and therefore worse outcomes and survival 22–24 …”

Thyroid follicular renal cell carcinoma excluding thyroid metastases: A case report

“…Thyroid cancer often metastasises to the bone, lung, and liver and rarely to the kidney. There are <30 reported cases of renal metastasis of thyroid cancer origin, and the expression of TTF-1 and TG is both positive and strongly positive[ 16 , 17 ]. The specimens from our patient were repeatedly examined by the Pathology Department in our hospital, and both TTF-1 and TG continued to be absent.…”

Metastatic thyroid carcinoma mimicking as a primary neoplasia of the kidney: A case report

“…In contrast to high incidence of PTC, distant metastases of this thyroid histotype are rarely seen and generally presented as a single case report (14,15); however, follicular carcinomas usually represent a neoplastic aggressive entity able to metastasize more frequently compared with papillary carcinoma by haematogeneous spread to distant sites, such as lung, bone, but seldom skin and kidney (1,(3)(4)(5)13,14). Commonly, in unusual renal localization, thyroid metastases results as multiple/or bilateral nodules, probably related to the presence of venous vascular structures between the thyroid and kidney (6,7).…”

“…The aggressive behavior of PTC has been mainly revealed by the hematogenous occurrence of distant metastases in ~20-25% of cases, with more frequent localizations to the lungs and bones (1,2), while other unusual sites are represented by skin and skull base (3)(4)(5). In addition, the renal metastatic involvement from PTC represents a very rare event, accounting for <5% of cases (6,7); in fact, only 18 cases have been reported in the English literature, although an additional 30 cases have been reported in the Japanese literature (8)(9)(10)(11)(12)(13)(14). The main PTC able to determine vascular invasion and metastasize to the kidney is represented by differentiated follicular carcinoma, followed by Hurthle cell as well as poorly differentiated carcinomas, since papillary carcinoma usually presents a lymphatic metastatic spread (2,8,10).…”

“…The main PTC able to determine vascular invasion and metastasize to the kidney is represented by differentiated follicular carcinoma, followed by Hurthle cell as well as poorly differentiated carcinomas, since papillary carcinoma usually presents a lymphatic metastatic spread (2,8,10). Unfortunately, distant metastases may appear as the initial symptom of PTC with the thyroid function remaining unaltered (13)(14)(15)(16); hence, it is not surprising that metastases occurring in unusual sites may be misdiagnosed as primary cancer until the post-surgical pathological analysis has been carried out revealing the metastatic nature from PTC. In light of these conditions, an interesting case report is presented herein with a case of a large single renal metastasis from thyroid follicular carcinoma with some poorly differentiated associated foci.…”