Unusual case of solitary functioning bone metastasis from a "parathyroid adenoma": imagiologic diagnosis and treatment with percutaneous vertebroplasty--case report and literature review

Diagnosis and treatment of liver metastases of parathyroid carcinoma

INTRODUCTION

Parathyroid carcinoma (PC) is a very rare endocrine malignancy occurring in less than 1% of all cases of primary hyperparathyroidism (pHPT). The liver is the second most common target organ for distant metastases of PC, but no guidelines are available for the diagnosis and treatment of liver metastases. In this study, we attempted to summarize the characteristics of the diagnosis and treatment of liver metastases based on our patients and other cases reported in the literature.

MATERIALS AND METHODS

The files of all patients diagnosed with PC with liver metastases summarized at our center between 2000 and 2022 were reviewed, and three datasets from Medline, Web of Science, and Embase were systematically searched to identify relevant articles.

RESULTS

Three patients with liver metastases from our center and 11 patients from the literature were included in the study. All patients had pHPT with borderline remission of hypercalcemia after each operation. A total of 71.4% of the patients' liver lesions were found by abdominal CT scans, while 35.7% were found by MRI, PET-CT, and fine-needle aspiration biopsy (FNAB), which were also helpful for diagnosis. Eight of nine patients (88.9%) who underwent surgery, radiofrequency ablation (RFA), or transcatheter arterial embolization (TAE) were alive, and only one postoperative patient died after a follow-up of 60 months.

CONCLUSIONS

PC is a rare malignant tumor prone to recurrence and metastasis, and postoperative reviews should be carried out routinely. Abnormally elevated parathyroid hormone (PTH) and serum calcium can indicate recurrence or metastasis. Enhanced CT and MRI can provide valuable support for the diagnosis of liver metastases, but whether [18F]FDG-PET-CT, [18F]FCH-PET-CT, or [11C]choline-PET-CT can be used as a diagnostic basis requires further study. Resection of liver metastases, segmental hepatectomy, or RFA can significantly improve patients' symptoms.

Case Report: Abdominal Lymph Node Metastases of Parathyroid Carcinoma: Diagnostic Workup, Molecular Diagnosis, and Clinical Management

Parathyroid carcinoma (PC) is an orphan malignancy accounting for only ~1% of all cases with primary hyperparathyroidism. The localization of recurrent PC is of critical importance and can be exceedingly difficult to diagnose and sometimes futile when common sites of recurrence in the neck and chest cannot be confirmed. Here, we present the diagnostic workup, molecular analysis and multimodal therapy of a 46-year old woman with the extraordinary manifestation of abdominal lymph node metastases 12 years after primary diagnosis of PC. The patient was referred to our endocrine tumor center in 2016 with the aim to localize the tumor causative of symptomatic biochemical recurrence. In view of the extensive previous workup we decided to perform [18F]FDG-PET-CT. A pathological lymph node in the liver hilus showed slightly increased FDG-uptake and hence was suspected as site of recurrence. Selective venous sampling confirmed increased parathyroid hormone concentration in liver veins. Abdominal lymph node metastasis was resected and histopathological examination confirmed PC. Within four months, the patient experienced biochemical recurrence and based on high tumor mutational burden detected in the surgical specimen by whole exome sequencing the patient received immunotherapy with pembrolizumab that led to a biochemical response. Subsequent to disease progression repeated abdominal lymph node resection was performed in 10/2018, 01/2019 and in 01/2020. Up to now (12/2020) the patient is biochemically free of disease. In conclusion, a multimodal diagnostic approach and therapy in an interdisciplinary setting is needed for patients with rare endocrine tumors. Molecular analyses may inform additional treatment options including checkpoint inhibitors such as pembrolizumab.

Parathyroid carcinoma with sarcomatoid differentiation: a case report and literature review

Background

Parathyroid carcinoma (PC) is a rare thyroid tumor. PC with sarcomatoid differentiation(PCSD) is even rarer and its exact etiology remains unclear. We here report a case of PCSD, and present the clinicopathological features and pathological diagnosis and review the literature.

Case presentation

A 71-year-old man presented with a mass of 4.5 cm × 3.5 cm in the right neck. The tumor was composed of nest-like transparent cells, and the septum had heterotypic rhabdoid cells with sarcomatoid differentiation. Immunophenotype was as follows: myogenic differentiation 1(MyoD1), myogenin and desmin were positive; clear cells were positive for chromogranin A(CGA), synaptophysin(Syn) and GATA-3; and Ki-67 proliferation index was 40%. Hematoxylin and eosin staining and immunohistochemistry were performed. The patient was diagnosed with PCSD, and died 6 months after surgery.

Conclusions

PCSD is a rare type of primary parathyroid tumor with high malignancy and poor prognosis. Definitive diagnosis should be based on histopathological morphology and immunophenotype, and surgical treatment should be performed as soon as possible.

Parathyroid carcinoma

Parathyroid carcinoma (PC) is a rare disease with an indolent behavior due to the low malignant potential. The etiology is unknown. Somatic mutations of CDC73 gene, the same gene involved in the hyperparathyroidism-jaw tumor syndrome, can be identified in up to 70% of patients with PC and in one-third of cases the mutations are germline. Therefore, in patients who carry germline CDC73 gene mutations, its finding permits to identify the carriers among relatives and sometimes to early detect a parathyroid lesion in such subjects. The diagnosis of PC is commonly made after surgery, however there are some clinical/biochemical features that should raise the suspicion of PC, namely markedly elevated serum calcium and PTH levels, a large parathyroid lesion with suspected ultrasonographic features of malignancy, the damages of kidney and bones. The best chance of cure is the complete surgical resection with the en-bloc excision at the first operation, however several recurrences are often observed during the follow-up. Since PC is an indolent tumor with long-lasting survival and the death is due to complications of untreatable hypercalcemia, multiple surgical interventions with debulking of tumoral tissues along with medical treatment for reducing hypercalcemia are often needed. Patients with PC should be followed up along their lifetime.

Clinical characteristics and treatment outcomes of parathyroid carcinoma: A retrospective review of 234 cases

Parathyroid carcinoma (PC) is one of the rarest known types of cancer and has a moderate prognosis, with estimated 5- and 10-year overall survival rates between 78–85% and between 49–70%, respectively. To raise awareness of this disease, and to optimize its diagnosis, clinical management and prognosis, the present study retrospectively reviewed 234 cases of PC. A total of 226 cases of PC, which were archived between 1984 and 2015 in the three major databases of the Chinese population, were retrieved and pooled with the 8 cases diagnosed and treated at the Department of Thyroid Surgery of The First Hospital of Jilin University (Changchun, China) between June 2008 and December 2015. The clinicopathological features, diagnosis, surgical procedures and outcomes of these cases of PC were investigated. The review revealed that misdiagnosis has been a considerable issue, with >80% of the patients misdiagnosed prior to surgery, and the accuracy of intraoperative diagnosis based on frozen sections was only 15.04%. The use of radical resection as first-line therapy significantly improved the disease-free survival by ~8 years (log-rank, 20.956; P<0.001); and, at relapse, reoperation prolonged patient survival by ~7 years (log-rank, 35.322; P<0.001). Consistently, a Cox proportional hazards analysis indicated that radical resection as a first-line therapy reduced the risk of postoperative recurrence (P=0.030), and that reoperation following recurrence significantly improved patient survival (P=0.030). The 5- and 10-year cumulative disease-specific survival rates of the cases of PC were 83 and 67%, respectively. Notably, an increased mortality rate was observed among males with PC compared with female patients with PC. In summary, in the past 32 years (1984–2015), the majority of patients with PC have been misdiagnosed. Performing radical resection as the first-line therapy significantly reduces recurrence and improves patient survival time; and, following relapse, subsequent surgery has also been demonstrated to be an effective approach.

Primary hyperparathyroidism-jaw tumor syndrome: a confusing and forgotten diagnosis

Background

Primary hyperparathyroidism is caused by the excessive growth of parathormone secretion, its consequence being hypercalcemia. The parathyroid adenoma is responsible for over half of primary hyperparathyroidism cases. The mandibular tumor can be the initial sign in the case of primary hyperparathyroidism.

Case presentation

We present the case of a 33 year old patient with history of a mandibular operated tumor, repetitive pathological fractures and hypercalcemia manifestations. The level of the parathormone at the first measurement indicated a very high value. The parathyroid scintigraphy with 99mTc-MIBI (methoxy-isobutyl-isonitrile) evidenced a high uptake of the tracerin the superior mediastinum, suggestive for an ectopic parathyroid adenoma. The histopathological examination after surgery leads to the diagnosis of parathyroid adenoma.

The association between the primary hyperparathyroidism, the mandibular tumour, the clinical history and the nuclear imaging lead to the diagnosis of primary hyperparathyroidism – Jaw tumor syndrome.

Conclusion

The hyperparathyroidism - Jaw tumor syndrome has a special clinical importance because of the severe and progressive symptomatology, and because of the risk of developing neoplasia of parathyroid glands, which have a reserved prognosis.

Incidentalomas during imaging for primary hyperparathyroidism--incidence and clinical outcomes

Background

Imaging for pre-operative localisation of parathyroid glands in primary hyperparathyroidism is now routine. This has led to the detection of incidental lesions (incidentalomas) in other organs, the nature of which is not well characterised.

The aim of this study was to determine the incidence, characteristics and outcomes in patients who had incidental findings on parathyroid imaging.

Methods

Records of patients who underwent imaging for primary hyperparathyroidism over 2 years were reviewed to identify incidental lesions detected on parathyroid imaging. Patients with persistent or renal hyperparathyroidism were excluded. Details on the management of detected incidentalomas were obtained from patient records.

Results

Incidentalomas were identified in 17 of 170 patients (10 %) undergoing parathyroid imaging. Incidentalomas included thyroid (n = 11), breast (n = 3), lateral compartment of the neck (n = 1), lung (n = 1) and clavicle (n = 1). However, no disease of clinical significance needing treatment was detected on further investigation.

Conclusions

Although a significant proportion of patients undergoing parathyroid imaging had incidental lesions detected, these seem to be of little clinical significance. The morbidity and cost of further interventions on these incidentalomas need to be weighed against the benefits of routine imaging in improving outcomes of first-time surgery in patients with primary hyperparathyroidism.