S P E C I A L I m a g e
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F E A T U R E
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A Bone Scan, No Mistake! Amelie Decock, Frank De Geeter, An De Vriese, Pascale Depaepe, and Annick Van den Bruel Division of Endocrinology, Department of Internal Medicine (A.D., A.V.d.B.), Department of Nuclear Medicine (F.D.G.), Division of Nephrology, Department of Internal Medicine (A.D.V.), and Department of Pathology (P.D.), General Hospital Sint-Jan, 8000 Bruges, Belgium
58-year-old man presented with severe myalgia, arthralgia, and weight loss. Clinical examination showed dehydration and a right-sided supraclavicular node. Laboratory tests revealed acute kidney injury (serum creatinine, 4.79 mg/dL [normal, 0.70 –1.20]; blood urea nitrogen, 178 mg/dL [normal, 10 –50]; hypercalcemia, 18 mg/dL [normal, 8.6 –10.2]; hyperphosphatemia, 5.1 mg/dL [normal, 2.7– 4.5]; and a calcium phosphate product of 91.8 mg2/dL2 [normal, ⬍40]). The alkaline phosphatase was 163 U/L (normal, 40 –129), and 25-hydroxyvitamin D was 16 ng/mL (normal, ⬎20). The PTH level was markedly elevated to 2337 pg/mL (normal, 15– 65). Bone scintigraphy did not reveal bone metastasis but showed enhanced tracer accumulation in the thyroid, lungs, myocardium, stomach, and kidneys, suggesting metastatic calcifications (Figure 1A). The extreme hypercalcemia, the PTH elevation, and the palpable right-sided supraclavicular node raised the suspicion of a parathyroid carcinoma. Neck ultrasound showed a hypoechogenic mass at the lower border of the right thyroidal lobe, which was confirmed by magnetic resonance imaging (Figure 1B). En bloc resection of the parathyroid tumor and the right thyroidal lobe with ipsilateral central neck dissection was performed. Histopathology confirmed parathyroid carcinoma (Figure 2). Two years later the patient remains without evidence of recurrence. Parathyroid carcinoma is a rare disease. The incidence in Belgium between 2004 and 2011 was 0.03/100 000 person years (1). Metastatic calcification may occur when the calcium phosphate product exceeds 60 mg2/dL2, which it rarely does in primary hyperparathyroidism, because of hy-
A
Figure 1. A, Bone scintigraphy with technetium-99m hydroxymethylene diphosphonate (Tc-99m HDP). Diffuse tracer uptake is present in the thyroid, lungs, myocardium, stomach, kidneys, and even in proximal limb muscles. Uptake in bone is low. B, Axial T2-weighted magnetic resonance imaging slice showing rounded tumor (indicated by P) lateral to the right thyroid lobe.
pophosphatemia. In case of associated renal impairment, however, phosphate retention results in hyperphosphatemia (2, 3). Calcification occurs preferentially in an alkaline environment, explaining why lungs,
Figure 2. Histopathology of the parathyroid tumor. A, Hematoxylin and eosin section with nests of parathyroid cells beyond the fibrous capsule (arrows), indicating capsular invasion. B, CD34 immunohistochemical staining identifying vascular spaces, some containing tumor cells in their lumen (arrows). This is proof of vascular invasion.
ISSN Print 0021-972X ISSN Online 1945-7197 Printed in U.S.A. Copyright © 2014 by the Endocrine Society Received July 12, 2014. Accepted September 22, 2014. First Published Online September 24, 2014
doi: 10.1210/jc.2014-2915
J Clin Endocrinol Metab, December 2014, 99(12):4447– 4448
jcem.endojournals.org
The Endocrine Society. Downloaded from press.endocrine.org by [${individualUser.displayName}] on 18 December 2014. at 12:32 For personal use only. No other uses without permission. . All rights reserved.
4447
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Decock et al
A Bone Scan, No Mistake!
kidneys, and stomach are frequently involved. In part, this may also reflect the optimal action of alkaline phosphatases, which generate free phosphate, at an alkaline pH (4). Diphosphonate tracer accumulation occurs because of chemoabsorption onto soft tissue microcalcifications.
Acknowledgments We gratefully acknowledge Kris Henau for calculating the incidence of parathyroid carcinoma in Belgium. Address all correspondence and requests for reprints to: Annick Van den Bruel, MD, Division of Endocrinology, Department of Internal Medicine, General Hospital Sint-Jan,
J Clin Endocrinol Metab, December 2014, 99(12):4447– 4448
Ruddershove 10, 8000 Brugge, Belgium. E-mail: annick. [email protected]. Disclosure Summary: The authors have nothing to disclose.
References 1. Cancer Incidence in Belgium, 2011. Belgian Cancer Registry. Brussels, Belgium; 2013. 2. Aso Y, Sato A, Tayama K. Parathyroid carcinoma with metastatic calcification identified by technetium-99m methylene diphosphonate scintigraphy. Intern Med. 1996;35:392–395. 3. Davidson RM, Dhekne RD, Moore WH, Butler DB. Metastatic calcification in a patient with malignant parathyroid carcinoma. Correlation of clinical, surgical, radiographic, and scintigraphic findings. Clin Nucl Med. 1990;15:692– 696. 4. Chan ED, Morales DV, Welsh CH, McDermott MT, Schwarz MI. Calcium deposition with or without bone formation in the lung. Am J Respir Crit Care Med. 2002;165:1654 –1669.
The Endocrine Society. Downloaded from press.endocrine.org by [${individualUser.displayName}] on 18 December 2014. at 12:32 For personal use only. No other uses without permission. . All rights reserved.
i n
F E A T U R E
E n d o c r i n o l o g y
A Bone Scan, No Mistake! Amelie Decock, Frank De Geeter, An De Vriese, Pascale Depaepe, and Annick Van den Bruel Division of Endocrinology, Department of Internal Medicine (A.D., A.V.d.B.), Department of Nuclear Medicine (F.D.G.), Division of Nephrology, Department of Internal Medicine (A.D.V.), and Department of Pathology (P.D.), General Hospital Sint-Jan, 8000 Bruges, Belgium
58-year-old man presented with severe myalgia, arthralgia, and weight loss. Clinical examination showed dehydration and a right-sided supraclavicular node. Laboratory tests revealed acute kidney injury (serum creatinine, 4.79 mg/dL [normal, 0.70 –1.20]; blood urea nitrogen, 178 mg/dL [normal, 10 –50]; hypercalcemia, 18 mg/dL [normal, 8.6 –10.2]; hyperphosphatemia, 5.1 mg/dL [normal, 2.7– 4.5]; and a calcium phosphate product of 91.8 mg2/dL2 [normal, ⬍40]). The alkaline phosphatase was 163 U/L (normal, 40 –129), and 25-hydroxyvitamin D was 16 ng/mL (normal, ⬎20). The PTH level was markedly elevated to 2337 pg/mL (normal, 15– 65). Bone scintigraphy did not reveal bone metastasis but showed enhanced tracer accumulation in the thyroid, lungs, myocardium, stomach, and kidneys, suggesting metastatic calcifications (Figure 1A). The extreme hypercalcemia, the PTH elevation, and the palpable right-sided supraclavicular node raised the suspicion of a parathyroid carcinoma. Neck ultrasound showed a hypoechogenic mass at the lower border of the right thyroidal lobe, which was confirmed by magnetic resonance imaging (Figure 1B). En bloc resection of the parathyroid tumor and the right thyroidal lobe with ipsilateral central neck dissection was performed. Histopathology confirmed parathyroid carcinoma (Figure 2). Two years later the patient remains without evidence of recurrence. Parathyroid carcinoma is a rare disease. The incidence in Belgium between 2004 and 2011 was 0.03/100 000 person years (1). Metastatic calcification may occur when the calcium phosphate product exceeds 60 mg2/dL2, which it rarely does in primary hyperparathyroidism, because of hy-
A
Figure 1. A, Bone scintigraphy with technetium-99m hydroxymethylene diphosphonate (Tc-99m HDP). Diffuse tracer uptake is present in the thyroid, lungs, myocardium, stomach, kidneys, and even in proximal limb muscles. Uptake in bone is low. B, Axial T2-weighted magnetic resonance imaging slice showing rounded tumor (indicated by P) lateral to the right thyroid lobe.
pophosphatemia. In case of associated renal impairment, however, phosphate retention results in hyperphosphatemia (2, 3). Calcification occurs preferentially in an alkaline environment, explaining why lungs,
Figure 2. Histopathology of the parathyroid tumor. A, Hematoxylin and eosin section with nests of parathyroid cells beyond the fibrous capsule (arrows), indicating capsular invasion. B, CD34 immunohistochemical staining identifying vascular spaces, some containing tumor cells in their lumen (arrows). This is proof of vascular invasion.
ISSN Print 0021-972X ISSN Online 1945-7197 Printed in U.S.A. Copyright © 2014 by the Endocrine Society Received July 12, 2014. Accepted September 22, 2014. First Published Online September 24, 2014
doi: 10.1210/jc.2014-2915
J Clin Endocrinol Metab, December 2014, 99(12):4447– 4448
jcem.endojournals.org
The Endocrine Society. Downloaded from press.endocrine.org by [${individualUser.displayName}] on 18 December 2014. at 12:32 For personal use only. No other uses without permission. . All rights reserved.
4447
4448
Decock et al
A Bone Scan, No Mistake!
kidneys, and stomach are frequently involved. In part, this may also reflect the optimal action of alkaline phosphatases, which generate free phosphate, at an alkaline pH (4). Diphosphonate tracer accumulation occurs because of chemoabsorption onto soft tissue microcalcifications.
Acknowledgments We gratefully acknowledge Kris Henau for calculating the incidence of parathyroid carcinoma in Belgium. Address all correspondence and requests for reprints to: Annick Van den Bruel, MD, Division of Endocrinology, Department of Internal Medicine, General Hospital Sint-Jan,
J Clin Endocrinol Metab, December 2014, 99(12):4447– 4448
Ruddershove 10, 8000 Brugge, Belgium. E-mail: annick. [email protected]. Disclosure Summary: The authors have nothing to disclose.
References 1. Cancer Incidence in Belgium, 2011. Belgian Cancer Registry. Brussels, Belgium; 2013. 2. Aso Y, Sato A, Tayama K. Parathyroid carcinoma with metastatic calcification identified by technetium-99m methylene diphosphonate scintigraphy. Intern Med. 1996;35:392–395. 3. Davidson RM, Dhekne RD, Moore WH, Butler DB. Metastatic calcification in a patient with malignant parathyroid carcinoma. Correlation of clinical, surgical, radiographic, and scintigraphic findings. Clin Nucl Med. 1990;15:692– 696. 4. Chan ED, Morales DV, Welsh CH, McDermott MT, Schwarz MI. Calcium deposition with or without bone formation in the lung. Am J Respir Crit Care Med. 2002;165:1654 –1669.
The Endocrine Society. Downloaded from press.endocrine.org by [${individualUser.displayName}] on 18 December 2014. at 12:32 For personal use only. No other uses without permission. . All rights reserved.
