Primary non-neuroendocrine tumours of the pituitary gland and sella are rare lesions often challenging to diagnose. We describe two cases of clinically aggressive primary glomus tumour of the pituitary gland. The lesions occurred in a 63-year-old male and a 30-year-old female who presented with headache, blurred vision and hypopituitarism. Neuroimaging demonstrated large sellar and suprasellar tumours invading the surrounding structures. Histologically, the lesions were characterised by angiocentric sheets and nests of atypical cells that expressed vimentin, smooth muscle actin and CD34. Perivascular deposition of collagen IV was also a feature. Case 2 expressed synaptophysin. INI-1 (SMARCB1) expression was preserved. Both lesions were mitotically active and demonstrated a Ki-67 labelling index of 30%. Next-generation sequencing performed in case 1 showed no mutations in the reading frame of 37 commonly mutated oncogenes, including BRAF and KRAS. Four pituitary glomus tumours have previously been reported, none of which showed features of malignant glomus tumour. Similar to our two patients, three previous examples displayed aggressive behaviour.

垂体和蝶鞍的原发性非神经内分泌肿瘤是罕见的病变，通常难以诊断。我们描述了两例垂体的临床侵袭性原发性glomus肿瘤。病变发生在63岁的男性和30岁的女性，他们表现为头痛，视力模糊和垂体功能低下。神经影像学检查发现大型蝶鞍和鞍上肿瘤侵犯周围结构。从组织学上讲，病变的特征是表达波形蛋白，平滑肌肌动蛋白和CD34的非典型细胞的血管中心层和巢。胶原IV的血管周围沉积也是一个特征。病例2表达突触素。保留INI-1（SMARCB1）表达式。两种病变均具有有丝分裂活性，并显示30％的Ki-67标记指数。BRAF和KRAS。先前已报道了四例垂体性球蛋白瘤，但均未显示恶性球蛋白瘤的特征。与我们的两名患者相似，之前的三个示例显示出攻击性行为。