Pishdad Reza, Cespedes Lissette, Boutin Regine, Jaloudi Mohammed, Raghuwanshi Maya
Internal Medicine, Rutgers New Jersey Medical School, Newark, USA.
Endocrinology and Metabolism, Rutgers New Jersey Medical School, Newark, USA.
Cureus. 2020 Apr 4;12(4):e7539. doi: 10.7759/cureus.7539.
The term "collision tumor" is described as the coexistence of two or more histologically distinct neoplastic morphologies separated by normal tissue in the same organ. Simultaneous papillary thyroid carcinoma (PTC) and follicular thyroid carcinoma (FTC) of the same thyroid lobe is a very rare pathology. Herein, we report a case of PTC and FTC of the same thyroid lobe. A 79-year-old man was evaluated at our hospital for the presence of left hip pain of two-month duration after sustaining a physical trauma to the left side of his body three days prior to admission. X-ray imaging of the left femur revealed a large lytic bony lesion at the proximal end of left femur. Biopsy of the bone lesion was suggestive of FTC. Computed tomography (CT) of the neck revealed an enlarged thyroid with a cystic lesion in the left lobe of the thyroid gland. Total thyroidectomy was performed. Histopathology revealed two separate primary malignancies of PTC and FTC. Genetic studies for RAS gene mutation were negative. He was initiated on suppressive doses of levothyroxine following thyroidectomy. Three months after surgery, thyrotropin alfa stimulated 204.5 mCi I-131 was administered. At seven months of follow-up, the thyroglobulin level was in the lower end of the normal range and anti-thyroglobulin antibody (anti Tg) remained negative (< 1.0 IU/mL). He was doing well and reported no symptoms. For each type of well-differentiated thyroid cancers, several genes have been identified. However, thus far, no specific gene mutation responsible for the pathogenesis of the different tumor types has been described. Management of thyroid collision tumor is usually complex due to the presence of different pathology in the tumor tissues and given the fact that literature on this condition is limited. Typically, the treatment needs to be individualized. Our report brings up a concept that the occurrence is a rare phenomenon of simultaneous mutation of different genes that could give rise to different thyroidal neoplasms.
术语“碰撞瘤”是指在同一器官中，两种或更多种组织学上不同的肿瘤形态被正常组织分隔并存。同一甲状腺叶同时发生乳头状甲状腺癌（PTC）和滤泡状甲状腺癌（FTC）是一种非常罕见的病理情况。在此，我们报告一例同一甲状腺叶发生PTC和FTC的病例。一名79岁男性因入院前三天身体左侧遭受外伤后持续两个月的左髋部疼痛而在我院接受评估。左股骨的X线成像显示左股骨近端有一个大的溶骨性骨病变。骨病变活检提示为FTC。颈部计算机断层扫描（CT）显示甲状腺肿大，甲状腺左叶有一个囊性病变。行甲状腺全切除术。组织病理学显示PTC和FTC两种独立的原发性恶性肿瘤。RAS基因突变的基因研究为阴性。甲状腺切除术后开始给予抑制剂量的左甲状腺素。术后三个月，给予促甲状腺素α刺激后的204.5 mCi I-131。随访七个月时，甲状腺球蛋白水平在正常范围下限，抗甲状腺球蛋白抗体（抗Tg）仍为阴性（<1.0 IU/mL）。他情况良好，未报告任何症状。对于每种类型的分化型甲状腺癌，已经鉴定出了几种基因。然而，迄今为止，尚未描述导致不同肿瘤类型发病机制的特定基因突变。由于肿瘤组织中存在不同的病理情况，且关于这种情况的文献有限，甲状腺碰撞瘤的管理通常很复杂。通常，治疗需要个体化。我们的报告提出了一个概念，即这种情况的发生是不同基因同时突变导致不同甲状腺肿瘤的罕见现象。
