Gallo Daniela, Rosetti Sara, Marcon Ilaria, Armiraglio Elisabetta, Parafioriti Antonina, Pinotti Graziella, Perrucchini Giuseppe, Patera Bohdan, Gentile Linda, Tanda Maria Laura, Bartalena Luigi, Piantanida Eliana
Department of Medicine and Surgery, Endocrine Unit, University of Insubria, Varese, Italy.
Department of Oncology, ASST dei Sette Laghi, Varese, Italy.
Endocrinol Diabetes Metab Case Rep. 2020 Jun 4;2020. doi: 10.1530/EDM-20-0046.
Brown tumors are osteoclastic, benign lesions characterized by fibrotic stroma, intense vascularization and multinucleated giant cells. They are the terminal expression of the bone remodelling process occurring in advanced hyperparathyroidism. Nowadays, due to earlier diagnosis, primary hyperparathyroidism keeps few of the classical manifestations and brown tumors are definitely unexpected. Thus, it may happen that they are misdiagnosed as primary or metastatic bone cancer. Besides bone imaging, endocrine evaluation including measurement of serum parathyroid hormone and calcium (Ca) levels supports the pathologist to address the diagnosis. Herein, a case of multiple large brown tumors misdiagnosed as a non-treatable osteosarcoma is described, with special regards to diagnostic work-up. After selective parathyroidectomy, treatment with denosumab was initiated and a regular follow-up was established. The central role of multidisciplinary approach involving pathologist, endocrinologist and oncologist in the diagnostic and therapeutic work-up is reported. In our opinion, the discussion of this case would be functional especially for clinicians and pathologists not used to the differential diagnosis in uncommon bone disorders.
Brown tumors develop during the remodelling process of bone in advanced and long-lasting primary or secondary hyperparathyroidism. Although rare, they should be considered during the challenging diagnostic work-up of giant cell lesions. Coexistence of high parathyroid hormone levels and hypercalcemia in primary hyperparathyroidism is crucial for the diagnosis. A detailed imaging study includes bone X-ray, bone scintiscan and total body CT; to rule out bone malignancy, evaluation of bone lesion biopsy should include immunostaining for neoplastic markers as H3G34W and Ki67 index. If primary hyperparathyroidism is confirmed, selective parathyroidectomy is the first-line treatment. In advanced bone disease, treatment with denosumab should be considered, ensuring a strict control of Ca levels.
棕色瘤是破骨细胞性良性病变，其特征为纤维性间质、丰富血管化及多核巨细胞。它们是晚期甲状旁腺功能亢进症中发生的骨重塑过程的终末表现。如今，由于早期诊断，原发性甲状旁腺功能亢进症很少出现典型表现，棕色瘤更是绝对意想不到的情况。因此，它们可能被误诊为原发性或转移性骨癌。除了骨成像外，包括血清甲状旁腺激素和钙（Ca）水平测量在内的内分泌评估有助于病理学家做出诊断。本文描述了一例被误诊为不可治疗的骨肉瘤的多发性大棕色瘤病例，特别关注诊断检查。在选择性甲状旁腺切除术后，开始使用地诺单抗治疗并建立定期随访。报告了病理学家、内分泌学家和肿瘤学家多学科方法在诊断和治疗检查中的核心作用。我们认为，讨论这个病例尤其对不熟悉罕见骨病鉴别诊断的临床医生和病理学家有帮助。
棕色瘤在晚期和长期原发性或继发性甲状旁腺功能亢进症的骨重塑过程中发展。虽然罕见，但在具有挑战性的巨细胞病变诊断检查中应予以考虑。原发性甲状旁腺功能亢进症中甲状旁腺激素水平升高和高钙血症并存对诊断至关重要。详细的影像学检查包括骨X线、骨闪烁扫描和全身CT；为排除骨恶性肿瘤，骨病变活检评估应包括对肿瘤标志物H3G34W的免疫染色和Ki67指数。如果原发性甲状旁腺功能亢进症得到证实，选择性甲状旁腺切除术是一线治疗方法。在晚期骨病中，应考虑用地诺单抗治疗，确保严格控制钙水平。
