Metastatic carcinoma to the thyroid gland from renal cell carcinoma: role of ultrasonography in preoperative diagnosis

Characterization of thyroid metastasis from clear cell renal cell carcinoma on ultrasonography: a report of three cases and literature review

Introduction

Thyroid metastasis from clear cell renal cell carcinoma (ccRCC) is relatively rare, so ultrasound doctors lack experience with the disease, which can easily lead to misdiagnosis. We describe three cases of thyroid metastasis from ccRCC detected 12, 8, and 7 years after nephrectomy.

Case presentation

The first patient, a 78-year-old woman, was admitted to our institution for hoarseness and progressive dyspnea. Ultrasonography revealed bilateral thyroid nodules and abnormal cervical lymph nodes. Fine-needle aspiration biopsy (FNAB) and core needle biopsy (CNB) of the thyroid was nondiagnostic. The other two patients, a 54-year-old man and a 65-year-old man, were admitted to our institution for a goiter pressing on the trachea. In each case, ultrasonography revealed a partially cystic nodule of the left lobe of the thyroid gland. Histological examination of three patients after thyroidectomy showed thyroid metastasis from ccRCC.

Discussion/Conclusion

For patients with a history of ccRCC, long-term follow-up and routine thyroid ultrasonography should be performed. If a new thyroid nodule is found during the examination, metastases should be highly suspected. FNAB should be performed, even if benign ultrasound features seem to be in evidence. If the diagnosis of FNAB is incorrect and inconclusive, CNB should be performed.

A Case of Metastatic Renal Cell Carcinoma to Thyroid Gland Mimicking as Anaplastic Thyroid Carcinoma

Metastatic cancers to the thyroid gland are rare, while the kidney is the most common primary site for metastatic cancers, occupying 42%. Metastatic renal cell carcinoma (RCC) to the thyroid gland usually has no specific symptoms or signs, and no characteristic imaging findings. And metastatic RCC takes a long time to occur after curative treatment. Since RCC rarely metastasizes only to the thyroid gland without the metastasis of other organs, it is difficult to distinguish it from thyroid nodules or cancers with a relatively high prevalence. Unlike metastases from the breast or lung, metastatic RCC to the thyroid gland is difficult to diagnose by a fine needle aspiration biopsy, which is usually confirmed by immunohistochemical analysis after surgery. Therefore, it is difficult to establish a treatment strategy before surgery. Recently, we experienced a rare case of metastatic RCC to the thyroid gland mimicking as anaplastic thyroid carcinoma because of its aggressive clinical course.

Solitary Intrathyroid Metastasis Occurring 23 Years after Resection of Renal Cell Carcinoma

A case of solitary intrathyroid metastasis is described in a 60-year-old male patient. He had a history of renal cell carcinoma classified as T1b resected 23 years earlier. A mass was palpable in the right thyroid lobe. Ultrasound showed a hypoechoic polylobular nodule with intense vascularisation in the right lobe. Fine needle aspiration cytology was normal, but thyroidectomy was performed due to mass enlargement, the ultrasound pattern, and the oncological history. Histological examination revealed the presence of an intrathyroid metastasis of renal cell carcinoma. The bone scan and thoracoabdominal CT scan were normal. Postoperative care was uneventful.

A Rare Case of Metastasis of Renal Clear Cell Carcinoma to the Thyroid Gland, Presenting as a Goiter Nodule, Three Years After Nephrectomy

Thyroid gland metastatic tumors are rare in clinical practice. Clear cell RCC is one of common metastatic tumors to thyroid. We here reported a case of incidentally found clear cell renal carcinoma metastasis to the thyroid gland 3 years after nephrectomy, in the thyroidectomy procedure performed for the patient due to the thyroid enlargement caused by multinodular goiter. A 65-year-old Iranian man with a history of multinodular goiter referred to our surgery clinic for thyroidectomy because of compressive effects on the trachea. Patient had a history of nephrectomy due to clear cell RCC 3 years ago. After thyroidectomy, gross and histological examination of thyroid revealed clear cell renal carcinoma metastasis to the thyroid gland in the setting of a multinodular goiter. The diagnosis was confirmed by immunohistochemistry staining. Patients with multinodular goiter are more prone to present with metastasis to thyroid gland if they have a history of malignancy, especially renal cell carcinoma.

Characteristics of clear cell renal cell carcinoma metastases to the thyroid gland: A systematic review

BACKGROUND

Thyroid gland is an uncommon site for metastases from clear cell renal cell carcinoma (CCRCC) and literature is scarce. Due to the variable and often long lag time before development of metastases in patients with CCRCC, thyroid nodules may be misdiagnosed initially as benign. This systematic review aims at a better understanding of the nature of these metastases.

METHODS

A bibliographic search was performed using PubMed (1990-2019), key words being “renal cell carcinoma, thyroid, kidney cancer, clear cell.” 147 cases were analyzed. The patient’s characteristics assessed were: age, sex, stage, size of metastases, lag time, diagnostic modality, initial symptoms, treatment and outcome in last documented follow up. Binary logistic regression, Spearman’s rho and ANOVA were used to identify differences between the existing variables.

RESULTS

The mean age (± SD) was 64 ± (10) years in males and 64 (± 11) in females. The mean lag time to diagnosis of thyroid metastases was 8.7 (± 6.3) years. Gender distribution of the patients was 46.3% male, 52.4% female. There was a weak correlation between lag time and size of metastases, not statistically significant. Size of metastases was significantly higher in symptomatic patients (6.06 ± 3.51 cm) compared to those with painless mass (4.6 ± 0.29 cm) and asymptomatic ones (3.93 ± 1.99 cm) (P = 0.03). Fine Needle Aspiration was diagnostic in 29.4% of cases, 47.1% were non diagnostic. Most patients (80.3%) underwent thyroid surgery. At 1 year follow up, 55.6% of patients operated were alive versus 35.3% who did not have surgery, though this was not statistically significant (P = 0.1).

CONCLUSION

A larger size of thyroid metastasis was more likely to present with symptomatology. A high index of suspicion is warranted when evaluating thyroid nodules in CCRCC patients. There was no significant difference in outcome between patients who underwent surgery and those who did not. With the wider use of immune check-point inhibitors and tyrosine kinase inhibitors in metastatic CCRCC, surgery may eventually be reserved only for palliative purposes.

A Multimodal and Pathological Analysis of a Renal Cell Carcinoma Metastasis to the Thyroid Gland 11 Years Post Nephrectomy

Thyroid lesions have a comprehensive differential diagnosis which include benign and malignant entities, such as metastases. However, metastases only account for a small percentage of thyroid lesions with renal cell carcinoma as the most common. Metastases to the thyroid pose a diagnostic dilemma as symptoms may not manifest for up to decades after removal of the renal cell carcinoma. Due to the nonspecific appearance on computed tomography and ultrasound, distinguishing metastases from primary thyroid malignancies is of the utmost importance for timely patient management. Our case demonstrates the importance of considering RCC metastases to the thyroid even years after nephrectomy to mitigate potential delays in diagnosis. We present the case of a 66-year-old male with a past medical history of renal cell carcinoma status post nephrectomy 11 years prior who demonstrated incidental thyroid abnormalities on positron emission tomography/computed tomography and ultrasound later confirmed as a metastasis of renal cell carcinoma.

Didactic surgical experience of thyroid metastasis from renal cell carcinoma: A case report

BACKGROUND

The optimal therapeutic strategy in treating thyroid metastasis from renal cell carcinoma (RCC) has not been clearly established. Here we describe a case of didactic surgical experience of the disease which caused massive intraoperative bleeding.

CASE SUMMARY

A 59-year-old male patient presented with a thyroid left lobe soft mass detected by chest computed tomography scans prior to the surgical treatment of RCC of the left kidney. The thyroid mass was initially considered to be benign, then he underwent left radical nephrectomy. One year after the nephrectomy, stereotactic radiosurgery was performed for brain metastasis. During follow-up, the thyroid nodule gradually grew, and the patient manifested swallowing discomfort. Under a clinical diagnosis of thyroid follicular neoplasm, left hemithyroidectomy was performed. Although hemithyroidectomy is usually a safe and straightforward procedure, massive bleeding from markedly developed tumor vessels made the operation very difficult. The thyroid tumor was finally diagnosed as metastasis from clear cell RCC.

CONCLUSION

For proper timing of the surgery, a clinician should take into consideration the possibility of thyroid metastasis of RCC when a thyroid lesion is found in patients with RCC or in patients with a previous history of RCC. We recommend that thyroid metastasis of RCC should be resected as early as possible even if a patient has other metastatic sites.

A Rare Case of Metastasis to the Thyroid Gland from Renal Clear Cell Carcinoma 11 Years after Nephrectomy and Concurrent Primary Esophageal Carcinoma

Renal cell carcinoma is known to cause metastasis to unusual sites, which can be both synchronous or metachronous. Thyroid gland is a rare site for metastasis, but when it occurs, renal cell carcinoma is the most common primary neoplasm. We report the case of a 81-year-old female patient who had a significant medical history of right clear cell renal carcinoma with adrenal metastasis. She underwent right radical nephrectomy and adrenalectomy followed by radiofrequency ablation of left adrenal metastasis and systemic chemotherapy with sunitinib. Eleven years later, she presented with dysphagia and was found to have distal esophageal adenocarcinoma. On imaging, there was incidental detection of a left renal mass lesion and a right thyroid nodule, which on histopathology and immunohistochemistry were confirmed to be clear cell carcinoma of renal origin.

Calcifications in Thyroid Tumors on Ultrasonography: Calcification Types and Relationship with Histopathological Type

PURPOSE

The purpose of the study is to clarify the prevalence of calcifications within thyroid tumors on ultrasonography as well as the relationship between the calcification and histopathological types.

MATERIALS AND METHODS

Calcifications were classified into 6 (or 8) types according to their shape, size, and region. The prevalence of calcifications and types were investigated in new outpatients and patients who underwent thyroid surgery.

RESULTS

Among 2,902 nodules in 2,678 new outpatients, 747 nodules (26%) had calcifications. The types showed a wide distribution. Among 941 patients with papillary carcinoma (PC), 725 patients (77%) had calcifications, and the types showed a wide distribution. 18 patients with the diffuse sclerosing variant of PC only showed punctate microcalcifications in the parenchyma (100%), 32 patients with the cyst-forming type of PC mostly fragmentary and massive types (100%), and 161 metastatic lymph nodes from PC mostly punctate microcalcifications and fragmentary types (48%). Among 337 patients with follicular carcinoma, 79 patients (23%) had calcifications, and the types were mostly fragmentary, massive, and egg-shell types. Among 41 patients with undifferentiated carcinoma, 33 patients (80%) presented with calcifications, which were mostly the massive and egg-shell types. Among 137 patients with medullary carcinoma, 99 patients (72%) had calcification, and the types showed a wide distribution. None of 173 patients with primary thyroid lymphoma had calcifications (0%).

CONCLUSION

Calcifications on ultrasonography can be one of the characteristic findings and a full understanding of the prevalence of calcifications and types will markedly contribute to the ultrasonic diagnosis of thyroid tumors.

Chromophobe renal cell carcinoma-like thyroid carcinoma: A novel clinicopathologic entity possibly associated with tuberous sclerosis complex

We report three cases of chromophobe renal cell carcinoma-like thyroid carcinoma as a novel clinicopathologic entity possibly associated with tuberous sclerosis complex. A 15-year-old female, a 19-year-old male, and a 21-year-old male presented with primary thyroid carcinoma. Two of the patients had associated tuberous sclerosis complex. Macroscopically, the carcinomas showed invasive growth. Histologically, the carcinoma cells showed a trabecular pattern with thin vascular stroma, and were characterized by abundant eosinophilic cytoplasm with perinuclear clearing, a prominent cell border, a wrinkled nuclear membrane, and binucleation, which are all features of chromophobe renal cell carcinoma. Immunohistochemically, the carcinoma cells were positive for thyroglobulin, TTF1, and PAX8, and negative for CD10, calcitonin, and carcinoembryonic antigen. Vascular invasion was visible in all cases, but distant metastasis was not detected during follow-up. The original pathological diagnoses of the three cases were widely invasive follicular thyroid carcinoma, poorly differentiated thyroid carcinoma, and oxyphilic variant of papillary thyroid carcinoma. Thus, the cases were similar to chromophobe renal cell carcinoma associated with tuberous sclerosis complex as they were characterized by histologic findings consistent with chromophobe renal cell carcinoma, occurrence in an adolescent or young adult, and favorable prognosis regardless of the presence of vascular invasion and an infiltrating growth pattern resembling poorly differentiated carcinoma. The etiopathogenesis also seemed to suggest the presence of the tuberous sclerosis complex genetic abnormality.

Metastasis of Renal Clear Cell Carcinoma to Thyroid Gland Mimicking Adenomatous Goiter

Background

Renal cell carcinoma is an interesting tumor due to its unpredictable behavior. Common metastatic sites of renal cell carcinoma are the lungs, lymph nodes, bones and liver. Concurrent thyroid metastasis of clear cell carcinoma is uncommon but it can appear as a rapidly growing cervical, painless nodular mass.

Case Report

We report a case of a 56-year-old male patient with clear cell renal carcinoma confirmed on a histopathological examination. The patient noticed a rapidly growing mass in the thyroid region when receiving medical anticancer therapy. Because of that, gray-scale thyroid ultrasonography and a fine-needle aspiration biopsy were performed. The histopathological examinationof the biopsy specimen revealed a lesion composed of malignant epithelial cells compatible with metastasis of renal carcinoma.

Conclusions

In patients with with a history of RCC, both past and present, a thyroid mass, especially co-existing with an adenomatous goiter, should prompt a work-up for thyroid metastasis.

Diffuse thyroid metastases and bilateral internal jugular vein tumor thrombus from renal cell cancer

Renal cell cancer rarely metastasizes to the thyroid gland, and it has been reported to present as a solitary mass. We present a case of diffuse thyroid cancer metastases from renal cell cancer. Bilateral internal jugular vein tumor thrombi were also present. To the best of our knowledge, this is the first description of diffuse thyroid metastases from renal cell cancer in the English literature. Renal cell cancer metastases should be considered in the differential of thyroid imaging abnormalities arising in the setting of known renal cell carcinoma, particularly late in the course of disease. This is frequently associated with internal jugular vein thrombi, which should be evaluated with an abnormal thyroid. Thyroglobulin levels are usually normal in such patients.

Metastatic renal cell carcinoma in the thyroid gland: ultrasonographic features and the diagnostic role of core needle biopsy

PURPOSE

The aims of this study were to present the ultrasonographic (US) features of metastatic renal cell carcinoma (RCC) in the thyroid gland and to evaluate the diagnostic utility of fineneedle aspiration (FNA) and core needle biopsy (CNB).

METHODS

Eight patients with nine metastatic RCC nodules in the thyroid glands who were treated from January 2002 to March 2015 in a single tertiary hospital were consecutively selected and retrospectively reviewed. US features and clinical history were obtained from the institution's medical database. FNA was performed nine times on eight nodules and CNB was performed six times on six nodules. The diagnostic utility of FNA and CNB was evaluated.

RESULTS

All nine nodules showed mass formation without diffuse thyroid involvement. On ultrasonography, metastatic RCC nodules were solid (100%), hypoechoic (100%), and ovalshaped nodules with a well-defined smooth margin (88.9%) and increased vascularity (100%, with 55% showing extensive vascularity). No calcifications were noted in any nodules. Lymph node metastasis and direct extension to nearby structures beyond the thyroid gland were not found. One FNA (11%) was able to confirm metastatic RCC, whereas all six CNBs confirmed metastatic RCC.

CONCLUSION

Metastatic RCC appears as oval-shaped hypoechoic solid nodules with well-defined smooth margins, no calcifications, and increased vascularity on ultrasonography. Characteristic US features along with a previous history of RCC should raise clinical suspicion, and CNB should be performed to make an accurate diagnosis.

Metastasis of renal cell carcinoma to the parathyroid gland 16 years after radical nephrectomy: A case report

Renal cell carcinoma (RCC) has a high metastatic potential, and most commonly metastasizes via the bloodstream, although lymphatic metastases also occur. RCC is well-known for its propensity to metastasize to unusual sites, and late metastasis, even after a number of years, is common. The occurrence of RCC metastasis to the head and neck region is uncommon, and occurs primarily in the thyroid gland and in patients with widespread dissemination. Involvement of the parathyroid gland in metastatic carcinoma is extremely rare. In the present report, a case of metastasis confined to the parathyroid gland is described, likely with intrathyroidal localization, arising from a RCC that occurred 16 years after nephrectomy. A 66-year-old man was referred to the Department of Surgery of the University Hospital of Pisa (Pisa, Italy) with a preoperative fine-needle aspiration diagnosis of a follicular lesion in the context of nodular goiter of the thyroid gland. The previous medical history of the patient included a right nephrectomy for the treatment of clear cell RCC in February 1997. No other distant metastases were identified as of the latest follow-up in March 2014. At the time of thyroid surgery, the thyroid and parathyroid function tests were normal. The gross appearance of the surgical specimen was a multinodular goiter with a solid nodule measuring 33 mm on the left lobe of the thyroid gland. Microscopic examination revealed a completely encapsulated lesion consisting of clear cells arranged in a solid pattern and intermixed with fragments of parathyroid tissue. Following immunohistochemical examination, the clear cell lesion was negative for thyroid transcription factor-1 and thyroglobulin and strongly positive for epithelial membrane antigen, cluster of differentiation 10 and vimentin. To the best of our knowledge, this is the second case of metastasis to the parathyroid gland from a RCC reported in the literature.

THYROID METASTASIS FROM CLEAR CELL CARCINOMA OF THE KIDNEY 16 YEARS AFTER NEPHRECTOMY

The thyroid gland is one of the most vascularized organs in the body. However, metastatic disease to the thyroid gland is rare. When it does occur kidney is the most common primary tumor site, followed by melanoma, lung, breast, esophagus, uterus and colon carcinoma. We describe the case of an isolated thyroid metastasis from clear cell renal carcinoma occurring 16 years after nephrectomy. An 82 years-old woman presented for the recent growth of a right thyroid nodule, diagnosed 3 years before, when a fine needle aspiration biopsy found a benign cytology suggesting a well-differentiated follicular thyroid adenoma. Her medical history included type 2 diabetes mellitus, atrial fibrillation and a right nephrectomy for a clear cell renal carcinoma done 16 years before. The patient has lost weight but she was otherwise asymptomatic. The right lobe goiter was painless, firm, and mobile with deglutition, without signs of local compression or latero-cervical lymphadenopathy. Thyroid ultrasonography revealed an enlarged (9.9 cm) macronodular right lobe, with multiple cystic areas, with normal left lobe and a thrombus in the right internal jugular vein. Thyroid function tests were normal. The patient was suspected of thyroid carcinoma and underwent a near total thyroidectomy. Histopathological examination revealed a metastasis of clear cell renal carcinoma in the right thyroid gland lobe (8.5/5/5 cm). Further imaging showed no primary tumor or other metastases. Metastatic renal carcinoma to the thyroid should be considered in any patient presenting with a thyroid mass and a medical history of operated renal cell carcinoma, since it can occur up to 25 years after nephrectomy.