Pathology Page
Metastatic Renal Cell Carcinoma Presenting as a Thyroid Mass A 55-year-old male presented to general surgery with symptoms of hyperthyroidism and a palpable thyroid nodule. In the preceding 5 months he noticed muscle weakness, tremors, weight loss and occasional palpitations. Ultrasound of the thyroid revealed a 4.4 cm nodule and fine needle aspiration was consistent with lymphocytic thyroiditis. Following discussion of treatment options he underwent thyroidectomy. Gross examination showed a single, encapsulated, tan-yellow nodule with focal hemorrhage. Microscopic examination revealed metastatic clear cell renal cell carcinoma (RCC) and a Hurthle cell neoplasm (fig. 1). RCC immunohistochemical (IHC) stain highlighted metastatic clear cell RCC (fig. 2). TTF-1 and thyroglobulin were positive in the Hurthle cell neoplasm. Computerized tomography of the chest, abdomen and pelvis revealed an 8 cm left renal mass, nephrometry score 9p, with no other evidence of disease. The patient was referred to urology. After discussion of treatment options he underwent
uncomplicated cytoreductive left laparoscopic radical nephrectomy and para-aortic lymph node dissection. The patient was discharged home on postoperative day 2 and will return for medical oncology evaluation for possible initiation of targeted therapy. Pathological examination of the radical nephrectomy specimen revealed Fuhrman grade III/IV clear cell RCC with all lymph nodes negative (AJCC TNM stage pT2a/N0/M1). Solid organ tumor metastasis to the thyroid gland is rare and accounts for fewer than 1% of diagnoses after thyroidectomy.1 Primary tumor sites to metastasize to the thyroid gland include kidney, lung, breast and skin with RCC representing the most common primary (33%).2 Thyroid metastasis of RCC more often presents in metachronous fashion.3 In a review of 150 cases of metastatic RCC to the thyroid from 1960 to 2008 the mean time between nephrectomy and thyroid metastasis was 7.5 years with 11 of the 150 cases (7%) occurring synchronously.1
Figure 1. Thyroid with Hurthle cell neoplasm surrounded by adipose tissue (left) and metastatic clear cell RCC (right).
Figure 2. RCC IHC stain highlights metastatic clear cell RCC (right) but is negative in Hurthle cell neoplasm (left).
0022-5347/15/1932-0677/0 THE JOURNAL OF UROLOGY® © 2015 by AMERICAN UROLOGICAL ASSOCIATION EDUCATION
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RESEARCH, INC.
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PATHOLOGY PAGE
The differential diagnosis of clear cell lesions found on pathological examination of the thyroid includes clear cell RCC and primary thyroid neoplasms with clear cell features. In patients with a history of RCC and nephrectomy a high level of suspicion should be maintained and a full metastatic evaluation should be done. Even in the absence of a previous cancer history consideration of metastatic RCC is important as the diagnosis will alter clinical management. Features favoring the diagnosis of metastatic RCC include multiple, well circumscribed nodules, infiltration of the thyroid capsule, clear (as opposed to granular) cytoplasm, hemorrhage and prominent vascular stroma with a sinusoidal pattern. A panel of IHC stains positive in RCC, including RCC, CD10 and Ksp-cadherin, may confirm the diagnosis.1,3 While PAX8 is a frequently used marker for metastatic RCC, it stains RCC and the thyroid, and is not useful in this scenario. In the era of targeted therapies for metastatic RCC patients must be carefully evaluated before nephrectomy.4 With good preoperative performance status and only 1 preoperative risk factor (symptomatic metastasis) our patient is likely to benefit from cytoreductive nephrectomy. Additionally,
retrospective studies demonstrated a survival benefit in patients with metastatic RCC who undergo complete metastasectomy.5 Eric H. Kim, Aaron M. Potretzke and R. Sherburne Figenshau Division of Urology Department of Surgery and
Carmen M. Perrino Department of Pathology and Immunology Washington University School of Medicine St. Louis, Missouri 1. Duggal NM and Horattas MC: Metastatic renal cell carcinoma to the thyroid gland. Endocr Pract 2008; 14: 1040. 2. Nakhjavani MK, Gharib H, Goellner JR et al: Metastasis to the thyroid gland. Cancer 1997; 79: 574. 3. Heffess CS, Wenig BM and Thompson LD: Metastatic renal cell carcinoma to the thyroid gland. Cancer 2002; 95: 1869. 4. Culp SH, Tannir NM, Abel EJ et al: Can we better select patients with metastatic renal cell carcinoma for cytoreductive nephrectomy? Cancer 2010; 116: 3378. 5. Alt AL, Boorjian SA, Lohse CM et al: Survival after complete surgical resection of multiple metastases from renal cell carcinoma. Cancer 2011; 117: 2873.
Metastatic Renal Cell Carcinoma Presenting as a Thyroid Mass A 55-year-old male presented to general surgery with symptoms of hyperthyroidism and a palpable thyroid nodule. In the preceding 5 months he noticed muscle weakness, tremors, weight loss and occasional palpitations. Ultrasound of the thyroid revealed a 4.4 cm nodule and fine needle aspiration was consistent with lymphocytic thyroiditis. Following discussion of treatment options he underwent thyroidectomy. Gross examination showed a single, encapsulated, tan-yellow nodule with focal hemorrhage. Microscopic examination revealed metastatic clear cell renal cell carcinoma (RCC) and a Hurthle cell neoplasm (fig. 1). RCC immunohistochemical (IHC) stain highlighted metastatic clear cell RCC (fig. 2). TTF-1 and thyroglobulin were positive in the Hurthle cell neoplasm. Computerized tomography of the chest, abdomen and pelvis revealed an 8 cm left renal mass, nephrometry score 9p, with no other evidence of disease. The patient was referred to urology. After discussion of treatment options he underwent
uncomplicated cytoreductive left laparoscopic radical nephrectomy and para-aortic lymph node dissection. The patient was discharged home on postoperative day 2 and will return for medical oncology evaluation for possible initiation of targeted therapy. Pathological examination of the radical nephrectomy specimen revealed Fuhrman grade III/IV clear cell RCC with all lymph nodes negative (AJCC TNM stage pT2a/N0/M1). Solid organ tumor metastasis to the thyroid gland is rare and accounts for fewer than 1% of diagnoses after thyroidectomy.1 Primary tumor sites to metastasize to the thyroid gland include kidney, lung, breast and skin with RCC representing the most common primary (33%).2 Thyroid metastasis of RCC more often presents in metachronous fashion.3 In a review of 150 cases of metastatic RCC to the thyroid from 1960 to 2008 the mean time between nephrectomy and thyroid metastasis was 7.5 years with 11 of the 150 cases (7%) occurring synchronously.1
Figure 1. Thyroid with Hurthle cell neoplasm surrounded by adipose tissue (left) and metastatic clear cell RCC (right).
Figure 2. RCC IHC stain highlights metastatic clear cell RCC (right) but is negative in Hurthle cell neoplasm (left).
0022-5347/15/1932-0677/0 THE JOURNAL OF UROLOGY® © 2015 by AMERICAN UROLOGICAL ASSOCIATION EDUCATION
AND
RESEARCH, INC.
http://dx.doi.org/10.1016/j.juro.2014.11.012 Vol. 193, 677-678, February 2015 Printed in U.S.A.
www.jurology.com
j
677
678
PATHOLOGY PAGE
The differential diagnosis of clear cell lesions found on pathological examination of the thyroid includes clear cell RCC and primary thyroid neoplasms with clear cell features. In patients with a history of RCC and nephrectomy a high level of suspicion should be maintained and a full metastatic evaluation should be done. Even in the absence of a previous cancer history consideration of metastatic RCC is important as the diagnosis will alter clinical management. Features favoring the diagnosis of metastatic RCC include multiple, well circumscribed nodules, infiltration of the thyroid capsule, clear (as opposed to granular) cytoplasm, hemorrhage and prominent vascular stroma with a sinusoidal pattern. A panel of IHC stains positive in RCC, including RCC, CD10 and Ksp-cadherin, may confirm the diagnosis.1,3 While PAX8 is a frequently used marker for metastatic RCC, it stains RCC and the thyroid, and is not useful in this scenario. In the era of targeted therapies for metastatic RCC patients must be carefully evaluated before nephrectomy.4 With good preoperative performance status and only 1 preoperative risk factor (symptomatic metastasis) our patient is likely to benefit from cytoreductive nephrectomy. Additionally,
retrospective studies demonstrated a survival benefit in patients with metastatic RCC who undergo complete metastasectomy.5 Eric H. Kim, Aaron M. Potretzke and R. Sherburne Figenshau Division of Urology Department of Surgery and
Carmen M. Perrino Department of Pathology and Immunology Washington University School of Medicine St. Louis, Missouri 1. Duggal NM and Horattas MC: Metastatic renal cell carcinoma to the thyroid gland. Endocr Pract 2008; 14: 1040. 2. Nakhjavani MK, Gharib H, Goellner JR et al: Metastasis to the thyroid gland. Cancer 1997; 79: 574. 3. Heffess CS, Wenig BM and Thompson LD: Metastatic renal cell carcinoma to the thyroid gland. Cancer 2002; 95: 1869. 4. Culp SH, Tannir NM, Abel EJ et al: Can we better select patients with metastatic renal cell carcinoma for cytoreductive nephrectomy? Cancer 2010; 116: 3378. 5. Alt AL, Boorjian SA, Lohse CM et al: Survival after complete surgical resection of multiple metastases from renal cell carcinoma. Cancer 2011; 117: 2873.
