Multiple brown tumors with primary hyperparathyroidism mimicking bone metastases []

Expect the unexpected: Brown tumor of the mandible as the first manifestation of primary hyperparathyroidism

Hyperparathyroidism (HPT) is a condition in which one or more parathyroid glands produce increased levels of parathyroid hormone (PTH), causing disturbances in calcium homeostasis. Most commonly HPT presents with asymptomatic hypercalcemia but the clinical spectrum may include disturbances reflecting the combined effects of increased PTH secretion and hypercalcemia. Brown tumors are rare, benign, tumor-like bone lesions, occurring in 1.5% to 4.5% of patients with HPT, as a complication of an uncontrolled disease pathway, and are nowadays rarely seen in clinical practice. The tumor can appear either as a solitary or multifocal lesion and usually presents as an asymptomatic swelling or a painful exophytic mass. Furthermore, it can cause a pathological fracture or skeletal pain and be radiologically described as a lytic bone lesion. The diagnosis of a brown tumor in HPT is typically confirmed by assessing the levels of serum calcium, phosphorus, and PTH. Although when present, brown tumor is quite pathognomonic for HPT, the histologic finding often suggests a giant cell tumor, while clinical presentation might suggest other more frequent pathologies such as metastatic tumors. Treatment of brown tumors frequently focuses on managing the underlying HPT, which can often lead to regression and resolution of the lesion, without the need for surgical intervention. However, in refractory cases or when dealing with large symptomatic lesions, surgical treatment may be necessary.

The value of integration of bone scan and targeted SPECT/CT in diagnosis of primary hyperparathyroidism with multiple bone brown tumor

Although parathyroid bone disease is rarely seen nowadays, skeletal manifestation can be the first sign of hyperparathyroidism (HPT) in some clinical practice. Nevertheless, the diagnosis of HPT is often overlooked. We describe three cases of multiple brown tumors (BT) in which bone pain and destruction were the first symptoms that masqueraded as a malignancy. However, according to the results of bone scan and targeted single-photon emission computed tomography/computed tomography (SPECT/CT), we considered BTs as the diagnosis in all of three cases. The final diagnoses were confirmed by laboratory tests and post-parathyroidectomy pathology. Parathyroid hormone (PTH) is significantly elevated in primary hyperparathyroidism (PHPT) as we know. However, such elevation is virtually never seen in malignancies. Diffuse or multiple foci of tracer uptakes in the bone scan were always seen in bone metastasis, multiple myeloma, and other bone neoplasm. When patients visited nuclear medicine for first consultation without biochemical results, radiological evidence from planar bone scan and targeted SPECT/CT can help in distinguishing the skeletal diseases. Lytic bone lesions with sclerosis, intra-focal or ectopic ossification and calcification, fluid-fluid level, and distribution of the lesions may be helpful in the differential diagnosis in these reported cases. In conclusion, when patients present with multiple foci of uptake on bone scan, targeted SPECT/CT is acquired for suspicious lesions, which can increase the diagnostic sensitivity and reduce unnecessary interventions and treatment. Moreover, BTs should be always kept in differential diagnosis of multiple lesions without a conclusive primary tumor.

Challenges of Differential Diagnosis Between Primary Hyperparathyroidism and Bone Metastases of Breast Cancer

Breast cancer might be complicated by distant metastases accompanied by hypercalcemia, but hyperparathyroidism is not commonly considered in the differential diagnosis. We present a case of 38 years old female patient who was diagnosed with ductal breast carcinoma. Eight months after the initial diagnosis the patient was diagnosed with distant bone metastases. However, this diagnosis was reconsidered at follow up, because we identified elevation of PTH 137.2 pg/ml, Ca²⁺ 1.19 mmol/l, albumin corrected calcium 2.42 mmol/l, 25(OH)D 39.4 nmol/l, indicating hyperparathyroidism. Scintigraphy with 99mTC-sestamibi confirmed parathyroid adenoma. Postoperative histopathology confirmed 1.2 g chief-cell PTA. Two months after the operation both PTH and Ca²⁺ levels were within the normal ranges. This study emphasizes the importance of considering possible hyperparathyroidism in patients with breast cancer and hypercalcemia. Routine evaluation of PTH is considered as a reasonable test in patients with breast cancer accompanied by bone lesions.

Bilateral Lipoadenoma of the Adrenal Glands and Humeral Brown Tumor: An Unusual Association

Adrenal adenolipomas are rare lipomatous adrenal tumors that can be either functional or not. Only 7 cases have been reported in the English literature so far. However, brown tumors are benign, rare, historical lesions, with histological similarity to giant tumors that can be encountered in 1% of all primary hyperparathyroidism cases. We report the case of an unusual association of bilateral lipoadenoma of the adrenal glands and humeral brown tumor in a 35-year-old patient. He presented to the emergency department with a pathological fracture of the left humerus secondary to a brown tumor. The medical investigations have concluded to primary hyperparathyroidism. The screening for multiple endocrine neoplasia type 1 revealed the presence of bilateral nonsecreting adrenal masses whose anatomopathological study concluded adenolipomas. Adrenal tumors may constitute a part of multiple endocrine neoplasia type 1 in 20 to 40% of cases. In this view, it is necessary to check for the presence of other endocrine gland tumor locations such as primary hyperparathyroidism, neuroendocrine tumors of the duodenum and pancreas, or pituitary adenomas.

The pathology femoral peritrochanteric fracture with multiple brown tumor as a first sign of parathyroid cancer - A case report

Introduction and importance

The parathyroid cancer is sometime only diagnosed after a pathological fracture has occurred, and pathology fracture is often misdiagnosed as a malignancy tumor. The treatment for pathology fracture and multiple bone lesions is not defined.

Case presentation

We report a 41-year-old case of parathyroid carcinoma in which pathological femoral fracture and brown tumors are the first clinical signs of the disease and that masqueraded as a malignancy tumor. The treatment for the patient was parathyroidectomy and then surgical treatment of the right femur with a locking plate osteosynthesis. Four months post-operative, the patient reported no pain and became capable of walking without a crutch. X-rays showed full bone union at fracture site of right femur, and brown tumors regression seen to be taking place in the upper limb, lower limbs and pelvis.

Clinical discussion

A brown tumor was diagnosed by a high concentration of blood parathyroid hormone and serum calcium. Despite the lack of clinical guidelines, most authors agreed that parathyroidectomy was the first choice of treatment then orthopaedic treatment. The principles of osteosynthesis of fracture were based on stable osteosynthesis. It was reported that osteolytic lesions caused by brown tumor were recovered when hyperparathyroidism had been treated.

Conclusion

Brown tumor needs to be considered in the differential diagnosis when there are osteolytic lesions and high serum calcium. It is advisable to have a parathyroidectomy and then orthopaedic treatment. Brown tumor with Mirels' score less than 7 scores should be applied a conservative treatment.

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Pathology fracture sometime is the first sign of parathyroid cancer and often misdiagnosed with bone malignant tumor.

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Parathyroidectomy is the first choice.

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The principles of osteosynthesis of pathology fracture are based on stable osteosynthesis.

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Brown tumor with Mirels' score less than 7 scores should be applied a conservative treatment.