Harinarayan Chittari Venkata, Ranjoalkar Anugnya Premdas, Tandon Anisha Sawkar, Ashok Honey, Prashant Madhu
Institute of Endocrinology, Diabetes, Thyroid and Osteoporosis Disorders, Sakra World Hospitals, Bangalore, Karnataka State, India.
Department of Medicine & Endocrinology, Saveetha Institute of Medical and Technical Sciences University, Saveetha Medical College, Chennai, India.
Endocr Oncol. 2025 May 31;5(1):e250024. doi: 10.1530/EO-25-0024. eCollection 2025 Jan.
Parathyroid carcinoma (PC) is a rare endocrine malignancy. It accounts for about 1% of all primary hyperparathyroidism (PHPT) cases and 0.005% of all malignancies. PC presents with severe hypercalcemia, often refractory to standard medical treatment, which is crucial for improving patient outcomes. Differentiating PC from atypical parathyroid adenomas and parathyromatosis can be challenging. PC is diagnosed by angio-invasion, lymphatic and perineural invasion, and local malignant invasion with regional and distant metastasis. CD31 positivity on immunohistochemistry, indicating tumor cells within blood vessels in the pseudocapsule (vascular invasion), and a Ki-67% proliferative index of 8% confirm the diagnosis. We describe a 67-year-old man who presented with neck swelling, abdominal pain, and weight loss. Five years prior, he underwent a left inferior parathyroidectomy for a mass, which histological examination identified as clear cell parathyroid adenoma. Three years post-parathyroidectomy, he developed recurrent left-sided neck swelling. Magnetic resonance imaging revealed a lesion with mediastinal extension but no lymph node metastasis. During surgery, the lesion was adherent to the common carotid artery, and histopathological examination confirmed parathyromatosis. Recently, he presented again with new-onset neck swelling, abdominal pain, and weight loss. Biochemical investigations confirmed primary hyperparathyroidism. Invasive growth into surrounding tissues, blood vessels, and nerves, along with lymph node involvement and lung metastasis, with histopathology showing CD31 positivity and a Ki-67% proliferative index of 8%, confirmed the diagnosis of PC. As the tumor was inoperable, hypercalcemia was managed with cinacalcet, resulting in a decline in serum calcium levels.
Parathyroid carcinoma is one of the rarest malignancies.Parathyromatosis is parathyroid tissue displaced in the neck and mediastinum due to prior surgery or aberrant embryonic development.The diagnosis of parathyroid carcinoma on histopathology is based on:Local invasion into adjacent structures, such as adipose tissues/skeletal muscle bundles.Loco-regional invasion-lymphatic (D240 IHC+), angio-invasion (CD31 IHC+), and perineural invasion.Nuclear pleomorphism, hyperchromatic nuclei, and increased mitosis (high Ki-67 proliferative index of >5%).Regional and distant metastasis in the lungs and other organs.Management of severe hypercalcemia is crucial for improving patient outcomes.
甲状旁腺癌（PC）是一种罕见的内分泌恶性肿瘤。它约占所有原发性甲状旁腺功能亢进症（PHPT）病例的1%，占所有恶性肿瘤的0.005%。PC表现为严重高钙血症，通常对标准药物治疗无效，这对改善患者预后至关重要。将PC与非典型甲状旁腺腺瘤和甲状旁腺增生症区分开来可能具有挑战性。PC通过血管侵犯、淋巴管和神经侵犯以及局部恶性侵犯伴区域和远处转移来诊断。免疫组织化学检测中CD31阳性，表明假包膜内血管中有肿瘤细胞（血管侵犯），Ki-67%增殖指数为8%可确诊。我们描述了一名67岁男性，他出现颈部肿胀、腹痛和体重减轻。五年前，他因肿块接受了左下甲状旁腺切除术，组织学检查确定为透明细胞甲状旁腺腺瘤。甲状旁腺切除术后三年，他出现左侧颈部反复肿胀。磁共振成像显示一个病变延伸至纵隔但无淋巴结转移。手术中，病变与颈总动脉粘连，组织病理学检查确诊为甲状旁腺增生症。最近，他再次出现新发颈部肿胀、腹痛和体重减轻。生化检查证实为原发性甲状旁腺功能亢进症。肿瘤侵入周围组织、血管和神经，伴有淋巴结受累和肺转移，组织病理学显示CD31阳性且Ki-67%增殖指数为8%，确诊为PC。由于肿瘤无法手术切除，高钙血症采用西那卡塞治疗，血清钙水平下降。
甲状旁腺癌是最罕见的恶性肿瘤之一。甲状旁腺增生症是由于先前手术或胚胎发育异常导致甲状旁腺组织移位至颈部和纵隔。甲状旁腺癌的组织病理学诊断依据为：局部侵犯相邻结构，如脂肪组织/骨骼肌束。局部区域侵犯——淋巴管侵犯（免疫组织化学D240阳性）、血管侵犯（CD31免疫组织化学阳性）和神经侵犯。核多形性、核深染和有丝分裂增加（Ki-67增殖指数>5%）。肺和其他器官的区域和远处转移。严重高钙血症的管理对改善患者预后至关重要。
