The management of parathyroid carcinoma

A case report of mediastinal parathyroid carcinoma in a chronic kidney disease patient: Addressing management conundrum

Parathyroid carcinoma is a rare malignancy; and it is rarer to find one located in an ectopic location. Ectopic parathyroid glands are a reported cause of failed primary surgery for hyperparathyroidism. We report here a 73-year-old male who previously had parathyroidectomy for primary hyperparathyroidism but then had recurrence of his symptoms with a diagnosis of a mediastinal parathyroid carcinoma on further evaluation. This presentation of complicated mediastinal parathyroid carcinoma posed significant diagnostic and management challenges due to comorbid stage IV chronic kidney disease (CKD). Secondly, due to the same comorbid condition, a more aggressive calcimimetic regimen could not be undertaken due to the risk of renal dysfunction with potential progression to dialysis status. Thirdly, he was a high-risk surgical candidate due to significant cardiovascular risks. Ideally, open surgical intervention would be recommended but due to the associated risks, he was managed with robotic-assisted thoracoscopic surgery. He subsequently developed hypocalcemia which normalized with supplemental calcium at follow-up.

Simultaneous Bilateral Quadriceps Tendon Rupture Secondary to Parathyroid Carcinoma: A Case Report

Simultaneous bilateral quadriceps tendon ruptures are a rare occurrence commonly associated with a traumatic event or systemic disease. A 31-year-old man presented with simultaneous bilateral quadriceps tendon ruptures with associated hyperparathyroidism secondary to parathyroid carcinoma. The injury occurred after the patient attempted to lift a small wooden log from the ground. We discussed the multidisciplinary management of this patient resulting in bilateral quadriceps tendon repairs, tumor resection, and oncological and endocrinological restoration. Clinical follow-up is reported at 15 years after surgery. Parathyroid carcinoma is an extremely rare cancer and rarely the cause of hyperparathyroidism. The systemic effects of the tumor eventually lead to the rupturing of both quadriceps tendons. Orthopaedic physicians must remain vigilant in identifying the root cause of injuries that are atypical in nature.

Radiation Treatment for Inoperable Local Relapse of Parathyroid Carcinoma With Symptomatic Hypercalcemia: A Case Report

BACKGROUND

Parathyroid carcinoma (PC) is an extremely rare malignancy, characterized by slow progression, frequent recurrences and difficult-to-control hypercalcemia which is typically the main contributor to the morbidity and mortality of these patients. Patients often undergo repeated surgical resections, whether or not in combination with adjuvant radiation treatment. The role of radiation therapy within the symptomatic treatment of PC currently remains unclear.

CASE DESCRIPTION

We describe a 30-year-old male patient with an inoperable local relapse of PC and secondary symptomatic hypercalcemia, maximally pharmacologically treated. After a local radiation treatment to a total dose of 70 Gray in 35 fractions serum calcium and parathyroid hormone (PTH) levels decreased, accompanied by improvement of the severe gastro-intestinal disturbances.

CONCLUSION

For patients with inoperable symptomatic PC despite maximal medical treatment who are in a good overall condition, radiation treatment can be considered in well-defined cases to decrease symptoms and improve quality of life.

Prognostic role of parafibromin staining and CDC73 mutation in patients with parathyroid carcinoma: A systematic review and meta-analysis based on individual patient data

BACKGROUND AND OBJECTIVE

Parathyroid carcinoma (PC) is a rare malignant neoplasm with a relatively poor prognosis. The loss of parafibromin expression or the presence of CDC73 mutation has been found to be remarkably associated with malignancy in parathyroid tumours. However, the prognostic role of them in PC has not yet been shown due to sampling limitations. We conducted a systematic review and meta-analysis based on individual patient data to clarify the performance of parafibromin immunohistochemical staining and CDC73 gene sequencing in predicting outcomes for patients PC.

METHODS

Published studies from PubMed/MEDLINE, EMBASE, Cochrane and Scopus Databases were searched using the terms 'parafibromin', 'CDC73', 'HRPT2' and 'parathyroid' to identify eligible studies. From the included studies, the survival data of patients with PC were extracted, and a Cox proportional hazards model was used to assess hazard ratio (HR) for disease-free survival (DFS) and overall survival (OS).

RESULTS

A total of 193 patients from 9 studies were included in this survival analysis. Negative immunohistochemical staining of parafibromin was shown to be a risk factor for recurrence/metastasis (HR 2.73, P = .002) and death (HR 2.54, P = .004). Patient age ≥ 50 years was significantly related to lower OS (HR 2.37, P = .004) but not to DFS. CDC73 mutation was not statistically related to DFS or OS.

CONCLUSIONS

Negative parafibromin staining indicated a higher risk of recurrence/metastasis and mortality. The immunohistochemical staining of parafibromin seems to be more promising in predicting outcomes for patients with PC than the sequencing of CDC73.

Atypical presentation of oncocytic parathyroid adenoma masquerading as metastatic carcinoma

Parathyroid carcinoma is the rarest endocrine malignancy. Definitive diagnosis is challenging as it is difficult to distinguish malignant from benign disease. A 71-year-old man presented with weight loss and hypercalcaemia. CT scans revealed multiple lung nodules and lytic bone lesions that were consistent with metastatic dissemination. Technetium-99m-sestamibi-single-photon emission computed tomography scan showed an abnormal uptake in the right thyroid lobe. Fine-needle aspiration (FNA) was performed on three occasions. The patient underwent parathyroidectomy with ipsilateral hemithyroidectomy without postoperative complications. Microscopic examination showed a parathyroid neoplasm with fibrosis and intravascular tumour on a background of unremarkable thyroid parenchyma. This resulted in an initial impression of parathyroid carcinoma. Further review by two independent pathologists provided a final diagnosis of oncocytic parathyroid adenoma. This case highlights the subjectivity and interobserver variation with endocrine histological examination. FNA can induce changes that mimic parathyroid carcinoma on histology. An index of suspicion for benign parathyroid adenomas should be maintained.

Parathyroid Carcinoma in a Chronic Hemodialysis Patient: Case Report and Review of the Literature

Parathyroid carcinoma is a rare disease in normal population as well as in patients with end-stage renal disease. Approximately 700 cases have been reported and, of these, 20 occurred in patients receiving chronic hemodialysis. We describe a case of parathyroid carcinoma in a 59-year-old female patient with end-stage renal disease secondary to membranous glomerulonephritis treated by hemodialysis since 1995. In September 1998, the calcium level was 12.4 mg/dl and intact parathyroid hormone serum levels were 1366 pg/ml (normal range, 25-65). A routine ultrasonographic examination of the neck revealed enlargement of two parathyroid glands, the left inferior gland being the largest and measuring 2×3×2 cm. In October 1998, resection of two parathyroid glands was performed. On the basis of histology, which documented the presence of proliferating cells arranged in sheets or in a trabecular pattern, numerous mitosis and vascular invasion, a diagnosis of parathyroid carcinoma was made.

Parathyroid carcinoma: From a case report to a review of the literature

INTRODUCTION

Parathyroid carcinoma is a rare endocrine malignancy. The reported incidence is from 0.5 to 5% of primary hyperparathyroidism cases in various series. Consideration of parathyroid carcinoma in the differential diagnosis of hypercalcaemic disorders is important because the morbidity and mortality are substantial and the best prognosis is associated with early recognition and surgical resection.

PRESENTATION OF CASE

We report a case of parathyroid carcinoma occurring in a 60-year-old woman who presented to our institution with persistent hyperparathyroidism and hypercalcemia 3 years after being submitted to one gland parathyroidectomy in another hospital.

DISCUSSION AND CONCLUSION

A review of the related literature follows.

Recent advances in the management of endocrine malignancies associated with hereditary hyperparathyroidism syndromes

Hereditary hyperparathyroidism syndromes, such as multiple endocrine neoplasm type 1, type 2A and the hyperparathyroidism-jaw tumor syndrome, are associated with an increased incidence of malignancies involving the neuroendocrine tissue of the pancreas and thymus, parathyroid and thyroid glands. The natural history of these endocrine tumors can differ from nonhereditary malignancies. The surgical approach, the only potentially curative treatment option for these endocrine malignancies, has evolved considerably in recent years. Newer targeted therapies, such as small molecule kinase inhibitors, somatostatin analogs and peptide receptor radionuclide therapy, are being developed. We provide here a comprehensive review of the current standards of treatment and emerging novel therapies for the endocrine malignancies commonly associated with hereditary hyperparathyroidism syndromes.

Parathyroid carcinoma

Parathyroid carcinoma is a rare form of endocrine malignancy accounting for only a small minority of cancer cases. Due to the rarity of this cancer, there are no generalized guidelines for its management; however, surgery remains to be the mainstay therapy. The purpose of this article is to review and summarize the available literature on parathyroid carcinoma, while discussing proposed staging systems and the role of available adjuvant therapies.

Parathyroid carcinoma: challenges in diagnosis and treatment

Parathyroid carcinoma is a malignant neoplasm affecting 0.5% to 5.0% of all patients with primary hyperparathyroidism. Since it was first described by De Quervain in 1904 to this day, it continues to defy diagnosis and treatment because of its rarity, overlapping features with benign parathyroid disease, and lack of distinct characteristics. En bloc surgical extirpation of the tumor with clear margins remains the best curative treatment. Although prolonged survival is possible with recurrent or metastatic disease, cure is rarely achievable. Efficacy of adjuvant therapies, such as radiotherapy and chemotherapy, in management of persistent, recurrent, or metastatic disease has been disappointing.

Intrathyroidal parathyroid carcinoma in a pediatric patient

Parathyroid carcinoma is unusual and its intrathyroidal variant is extremely rare. Therefore, few cases have been reported to describe a case of parathyroid carcinoma located inside the thyroid gland. The case corresponds to a 14-year-old girl who came to the office with a severe osteoarticular disease, depression, calcemia of 14.3 mg/dl and parathyroid hormone of 2,792 pg/ml. Right neck exploration was conducted and a parathyroid carcinoma was found located intrathyroidally. A right thyroid lobectomy was performed. A 20-month follow-up period revealed no recurrence of clinical or biochemical signs. In patients with severe hypercalcemia and significant elevation of parathyroid hormone, the diagnosis of parathyroid carcinoma has to be considered. It is worth highlighting the early age of presentation in this case. Treatment has allowed the effective control of the disease and its recommended long-term follow-up.

FDG-PET/CT and parathyroid carcinoma: Review of literature and illustrative case series

Parathyroid cancer is an uncommon malignant cancer and is associated with a poor prognosis. The staging of parathyroid cancer represents an important issue both at initial diagnosis and after surgery and medical treatment. The role of positron emission tomography/computed tomography (PET/CT) with 18F-Fluorodeoxyglucose (18F-FDG) as an imaging tool in parathyroid cancer is not clearly reported in the literature, although its impact in other cancers is well-defined. The aim of the following illustrative clinical cases is to highlight the impact of PET/CT in the management of different phases of parathyroid cancer. We describe five patients with parathyroid malignant lesions, who underwent FDG PET/CT at initial staging, restaging and post-surgery evaluation. In each patient we report the value of PET/CT comparing its findings with other common imaging modalities (e.g., CT, planar scintigraphy with 99mTc-sestamibi, magnetic resonance imaging) thus determining the complementary benefit of FDG PET/CT in parathyroid carcinoma. We hope to provide an insight into the potential role of PET/CT in assessing the extent of disease and response to treatment which are the general principles used to correctly evaluate disease status.

Hyperfunctional parathyroid carcinoma with mediastinal extension

Parathyroid carcinoma (PC) is an extremely rare malignancy, 0.005% of all tumours and between 0.5% and 5% of all parathyroid neoplasms. Preoperative diagnosis is often difficult and is almost always obtained only after post-surgical histopathology. The prognosis is related to the local extent of disease and to complete surgical resection of the tumour. We report an uncommon case of hyperfunctional PC with mediastinal extension, emphasising the diagnostic difficulties, histopathological features and treatment strategies. The most recent data in the literature is analysed as well.

Use of a gamma probe to identify and guide resection of recurrent parathyroid carcinoma: report of a case

Parathyroid carcinoma (PC) accounts for less than 0.005% of all cancers and less than 5% of causes of hyperparathyroidism. This tumor is difficult to identify during surgery, which is detrimental to the oncologic results. Surgery is still the main treatment for the primary tumor and to control parathyroid hormone levels after recurrence. We report a case of recurrent parathyroid carcinoma in a 30-year-old man, identified and managed with the use of a gamma probe during surgery. To our knowledge, this is only the second report of a gamma probe being used to guide resection of a recurrent PC. We discuss the diagnosis and treatment, analyzing the current evidence-based literature.

Focus on parathyroid carcinoma

Parathyroid carcinoma is a malignant neoplasm affecting 05-2 per cent of all patients with primary hyperparathyroidism that was first described by de Quevain in 1904. To day it continues to defy diagnosis and treatment. It is difficult to diagnose in part because of its rarity, lack of definitive diagnostic markers and overlapping clinical features of benign primary hyperparathyroidism. As a result initial surgical treatment is inadequate essentially leading to disease recurrence where complete cure is unlikely. En bloc surgical resection remains the only curative treatment, and high priorities are improving diagnostic methods, and clinical staging for resection once the disease is suspected. Margin status at resection is related to prognosis. Thus, a trend towards aggressive surgical management has improved outcomes. The recurrence rate of parathyroid carcinoma is as high as 80% with survival rates <50% at 10 years. Results of chemotherapy are disappointing. However, recent trials using radiation therapy are promising, but require further study.

Parathyroid carcinoma

Parathyroid carcinoma is a rare endocrine malignancy. The reported incidence is from 0.5 to 5% of primary hyperparathyroidism cases in various series. The cause is unknown, but clinical correlations with different genetic syndromes exist. Mutations in the HPRT2 gene seem to play a significant role in the pathogenesis of this disease. Men and women are equally affected, usually in the fourth or fifth decade of life. Most patients will present with signs and symptoms of hypercalcaemia. Cases of non-functioning carcinoma are exceedingly rare. Surgical resection is the most effective method of treatment and palliation. A significant proportion of patients will experience recurrence, and will need further surgical and, eventually, medical management of hypercalcaemia. The disease is progressive but slow growing. Most patients will require multiple operations to resect recurrent disease. The main cause of morbidity and mortality is the sequela of uncontrolled chronic hypercalcaemia rather than tumour burden. The current paper will review the epidemiology, pathogenesis, clinical presentation and diagnostic work-up of this disease. Surgical management in different scenarios is reviewed in detail, followed by other types of treatment and management of incurable disease.

Parathyroid carcinoma: a 16-year experience in a single institution

INTRODUCTION

This study aims to describe our experiences of parathyroid carcinoma.

MATERIALS AND METHODS

The data of clinicopathological features, surgical treatment and outcomes of seven cases of parathyroid carcinoma among 171 patients who underwent surgery for primary hyperparathyroidism over a 16-year period were analyzed.

RESULTS

The major symptoms at the diagnosis included a neck mass in three cases and multiple bone pain in five. Two patients were asymptomatic. No remarkable increases of serum calcium levels were noted in the patients, but serum parathyroid hormone (PTH) concentrations were high in most of the patients (4 of 5 in available). A variety of imaging studies including ultrasonography, sestamibi scan, and computed tomography scan were helpful in identifying the abnormal parathyroid glands, but not specific for the diagnosis of parathyroid carcinoma. In most patients, the parathyroid carcinomas were suspected at the time of neck exploration, and confirmed by final histopathologic examinations. All patients underwent complete surgical excision with curative intent. During the follow-up period, one patient developed lung metastases 6 years later and the other one died of unrelated cause.

CONCLUSION

Preoperative diagnosis of parathyroid carcinoma is difficult, but operative findings are helpful in the diagnosis. The optimal surgical treatment is en block radical resection including adjacent structures when parathyroid carcinoma is suspected. Unusually, although our patients presented with high serum PTH concentrations, they had normal or mild elevated serum calcium concentrations. The reason of why should be investigated in future studies.

En bloc spondylectomy for treatment of tumor-induced osteomalacia

En bloc spondylectomy represents a radical resection of a spinal segment most often reserved for patients presenting with a primary extradural spine tumor or a solitary metastasis in the setting of an indolent, well-controlled systemic malignancy. The authors report a case in which en bloc spondylectomy was conducted to control a metabolically active spine tumor. A 56-year-old woman, who suffered from severe tumor-induced osteomalacia, was found to have a fibroblast growth factor-23-secreting phosphaturic mesenchymal tumor in the T-8 vertebral body. En bloc resection was conducted, leading to resolution of her tumor-induced osteomalacia. This case suggests that radical spondylectomy may be beneficial in the management of metabolically or endocrinologically active tumors of the spine.

Primary hyperparathyroidism due to parathyroid carcinoma associated with pulmonary embolism

Parathyroid carcinoma (PC) is an uncommon disease affecting 0.5-5% of all patients with primary hyperparathyroidism. PC is characterized by the association of severe symptoms of hypercalcemia, high serum calcium and parathyroid hormone (PTH) concentrations and a palpable neck mass. Definitive diagnosis can only be made by histological study after surgery. We report the case of a 77-year-old man admitted to our hospital due to pulmonary embolism and hypercalcemia. The patient was initially diagnosed with primary hyperparathyroidism, but displayed the atypical clinical features described above. Due to clinical suspicion of PC, a surgical procedure was carried out. Diagnosis of parathyroid carcinoma was confirmed by histopathologic study.

[Parathyroid carcinoma]

BACKGROUND

Parathyroid carcinoma is the least frequent malignancy among endocrine tumors. In the most reported series of patients with primary hyperparathyroidism the incidence of carcinoma is less than 1%. Racognition by a surgeon that the parathyroid tumor is malignant, and the performance of an adequate en bloc removal of primary lesion, with histologic diagnosis offer the best treatment of a patient with this unusual malignancy.

CASE REPORT

We reported a 30-year-old patient with parathyroid carcinoma, primary hyperparathyroidism, and recurrent nephrocalcinosis. Marked hypercalcemia, low serum phosphorus, and substantial elevation of serum parathyroid hormone indicated a diagnosis of primary hiperparathyroidism. General symptoms were anorexia, muscle weakness, back pain and depression. Ultrasonography done before the surgery revealed a 2 cm upper left parathyroid gland with solid and cystic areas. The neck exploration was done with en block resection of the tumor. A histopathological evaluation confirmed the diagnosis of parathyroid carcinoma. Over more than a three-year-follow-up, the patient had no evidence of the disease recurrence and his serum PTH and calcium levels remained within the normal.

CONCLUSION

Parathyroid carcinoma is a rare cause of primary hyperparathyroidism. Preoperative diagnosis remains a challenge. Radical en bloc resection of the tumor is the treatment of choice for this malignancy.

Parathyroid Cancer

Parathyroid cancer is a rare endocrine tumor and an uncommon cause of HPT. Advances have been made to identify a promising molecular diagnostic marker for the disease. The use of accurate preoperative imaging modalities would undoubtedly facilitate its management by making an accurate preoperative diagnosis by assessing its invasiveness, and by searching for nodal or distant metastases. The effectiveness of the application of intraoperative PTH assay in the management of this rare condition remains to be seen. Radical surgical treatment offers the best chance of cure, but for patients who have refractory unresectable disease or metastases, the availability of more effective targeted medical therapy may palliate the debilitating symptoms of hypercalcemia, reduce its metabolic complications, and potentially improve survival.

Normocalcemic parathyroid carcinoma: an unusual clinical presentation

Background

Parathyroid carcinoma is a rare cause of primary hyperparathyroidism and may be associated with significant disease related morbidity and mortality. Preoperative diagnosis remains a challenge, which may jeopardize appropriate and successful patient treatment.

Case presentation

We report a case of parathyroid carcinoma diagnosed in a 60-year-old woman that presented with a tender nodule located at the left lower thyroid pole and had been present for several years. Ultrasound examination revealed a 2.7 × 1.6 × 2.7 cm mass within the lower left lobe of the thyroid with cystic and solid areas. Lab measurement of the intact PTH level revealed it to be three times the upper limit of normal and the serum calcium level was within normal limits. A left thyroid lobectomy and isthmusectomy was carried out. Histopathological evaluation was diagnostic for a parathyroid carcinoma. At greater than two years of follow-up, the patient has had no evidence of disease recurrence and her serum PTH and calcium levels have remained within normal.

Conclusion

Parathyroid carcinoma is a rare endocrine tumor which must be considered in the differential diagnosis of a nodular thyroid mass. En bloc resection remains the treatment of choice for this malignancy. Disease prognosis is influenced by the extent of the initial resection, the presence of metastases, and adequate long-term follow-up.

Parathyroid carcinoma

BACKGROUND

Parathyroid carcinoma is a rare malignancy affecting 0.5-5 per cent of all patients with primary hyperparathyroidism. This article reviews the literature on the pathogenesis, pathology, clinical features, diagnosis and management of parathyroid carcinoma.

METHODS

A Medline search was performed and all relevant English language articles published between 1970 and 2005 were retrieved. The search words included 'parathyroid carcinoma', 'pathology', 'genetics', 'management' and 'radiotherapy'. Secondary references were obtained from key articles.

RESULTS AND CONCLUSION

The exact aetiology of parathyroid carcinoma remains obscure. Recently, the HRPT2 gene has been implicated in its pathogenesis and may prove to be a genetic target in future. Surgical resection is the accepted 'gold standard'. There is now a growing consensus on the use of adjuvant radiotherapy as it has been shown to provide a survival benefit.

Parathyroid carcinoma: an overview

Parathyroid carcinoma is a rare tumor that is responsible for <1% of cases of hyperparathyroidism in most parts of the world. An increased incidence of this tumor has been reported in patients with the hyperparathyroidism-jaw tumor (HPT-JT) syndrome, but the etiology of most other cases is unknown. Parathyroid carcinomas tend to occur a decade earlier than adenomas, and the sex ratio approaches unity in contrast to the female preponderance of adenomas. Most patients with carcinomas present with marked hypercalcemia and are more likely to have associated bone and renal disease than those with adenomas. Although fibrosis and mitotic activity are common in carcinomas, these features are not specific for malignancy. The diagnosis of carcinoma should be restricted to those tumors that show invasion of blood vessels, perineural spaces, soft tissues, thyroid gland, or other adjacent structures or to tumors with documented metastases. Mutations of the HRPT2 gene (1q21-q32), which are responsible for the HPT-JT syndrome, have been implicated in the development of a high proportion of parathyroid carcinomas. A subset of patients with mutation-positive carcinomas have germline mutations of the HRPT2 gene. This finding suggests that some patients with apparent sporadic parathyroid carcinomas may have the HPT-JT syndrome or a variant of this syndrome. Because of the high frequency of local recurrence following incomplete excision, an en bloc resection is the preferred surgical approach for treatment of parathyroid carcinomas.