激素表达差异性垂体癌

目的报告1例原位和转移灶激素表达差异的垂体癌患者的临床诊断与治疗经过,以提高对该病的认识。方法与结果女性患者,50岁。临床主要表现为垂体腺瘤切除术后4个月眼部胀痛不适。MRI显示颅内多发异常信号,垂体形态欠规则,鞍区呈异常信号和强化影;PET-CT显示多发高摄取病灶。首次术后HE染色,肿瘤细胞弥漫性分布,呈圆形或多边形伴轻度异形,胞质中等量、嗜酸性,胞核圆形、染色质较细、核仁不明显,核分裂象易见,无坏死;免疫组织化学染色,肿瘤细胞分别表达P53、嗜铬素A,个别表达生长激素,Ki-67抗原标记指数约为80%,病理诊断为非典型垂体腺瘤。肿瘤复发转移后顶叶肿瘤活检术可见肿瘤浸润脑实质,肿瘤细胞弥漫表达生长激素,Ki-67抗原标记指数约为75%,病理诊断为转移性垂体癌。结论垂体癌为临床罕见的恶性垂体肿瘤,需结合影像学和术后组织病理学明确诊断。首选外科手术切除肿瘤灶,辅助术后放射治疗或药物化疗,患者多预后不良。     

垂体转移癌:一例报告并文献复习

研究背景垂体转移癌临床罕见,诊断难度较大,容易误诊,本文拟对其临床表现和组织病理学特征进行探讨。方法报告1例垂体转移性肺低分化腺癌患者的临床表现、组织病理学特征和免疫表型,并复习相关文献。结果女性患者,47岁。临床主要表现为头晕、头痛伴视物模糊,头部CT检查显示鞍上池软组织密度结节影。术中可见肿瘤位于鞍区,大小约为2cm×1cm×1cm。光学显微镜观察垂体结构破坏,肿瘤组织由明显异型性的圆形、卵圆形细胞组成,呈巢团状或腺样排列;肿瘤细胞表达上皮膜抗原、广谱细胞角蛋白、甲状腺转录因子1和细胞角蛋白7,不表达嗜铬素A、癌胚抗原、人绒毛膜促性腺激素、胎盘碱性磷酸酶、CD117、白细胞共同抗原、CD30和间变性淋巴瘤激酶1,Ki67抗原标记指数约为15%。术后辅助左甲状腺素钠和伽玛刀治疗,4个月后死亡。结论垂体转移癌可通过组织病理学和免疫组织化学检测明确诊断,同时寻找原发灶。术后需辅助综合治疗。     

右侧额叶转移性沙砾体型肺乳头状腺癌

目的报告1例临床罕见的右侧额叶转移性沙砾体型肺乳头状腺癌患者,结合文献探讨其临床病理学特点、诊断与鉴别诊断要点。方法与结果男性患者,56岁,临床表现为额枕部间歇性头痛。MRI显示右侧额叶占位性病变,考虑脑膜瘤可能。术中可见右侧额叶肿瘤呈灰红色、质地较韧、边界清楚、血供丰富。组织学形态观察,肿瘤组织呈乳头状结构,胞质嗜酸性,胞核呈圆形或卵圆形,可见小的红核仁,肿瘤组织和肿瘤间质中可见大量沙砾体形成;免疫组织化学染色,肿瘤细胞弥漫性表达细胞角蛋白(CK)、上皮膜抗原、CK19、甲状腺转录因子-1和Napsin A蛋白,灶性表达P53,Ki-67抗原标记指数为5%~10%;不表达胶质纤维酸性蛋白、S-100蛋白、甲状腺球蛋白、Galectin-3蛋白、孕激素受体、波形蛋白等标志物。结合胸部18F-FDG-PET CT显像,最终病理诊断为(右侧额叶)转移性沙砾体型肺乳头状腺癌。术后辅以放射治疗和药物化疗,随访12个月,肿瘤无复发。结论中枢神经系统转移性沙砾体型肺乳头状腺癌临床罕见,应详细了解病史,并注意与乳头状型脑膜瘤、脉络丛乳头状瘤、乳头状型室管膜瘤、乳头状型胶质神经元肿瘤和转移性甲状腺乳头状癌等相鉴别,以免误诊或漏诊。     

鞍区和鞍上脑室外神经细胞瘤

目的探讨发生于鞍区和鞍上的脑室外神经细胞瘤的临床病理学特征。方法对1例鞍区和鞍上脑室外神经细胞瘤患者的临床表现、影像学特征、组织学形态、免疫表型和分子遗传学特征进行回顾分析并复习相关文献。结果女性患者,27岁,临床表现为反复头痛伴双眼视物模糊5个月。头部MRI显示鞍区和鞍上占位性病变,T_1WI呈等或低信号,T_2WI呈高或低混杂信号,扩散加权成像呈稍高信号,界限清晰,正常垂体结构显示不清。临床诊断为垂体腺瘤,行经鼻蝶入路垂体腺瘤切除术+脑脊液鼻漏修补术+视神经减压术,手术全切除肿瘤。组织学形态可见肿瘤细胞呈弥漫浸润性生长,部分区域可见神经毡背景;肿瘤细胞大小和形态相对一致,胞核圆形或卵圆形,染色质细腻深染,未见核分裂象。免疫组织化学染色可见肿瘤细胞胞核表达神经元核抗原和甲状腺转录因子-1,胞核和胞质表达钙视网膜蛋白,胞质表达突触素、嗜铬素A、上皮钙黏素和基质金属蛋白酶-9;胞核局灶性表达S-100蛋白,胞质局灶性表达神经微丝蛋白、细胞角蛋白8和波形蛋白;Ki-67抗原标记指数约为3%。网织纤维染色呈阴性。基因检测可见肿瘤细胞无异柠檬酸脱氢酶基因突变,无1p/19q-共缺失。最终病理诊断为脑室外神经细胞瘤(WHOⅡ级)。结论鞍区和鞍上脑室外神经细胞瘤临床极为罕见,组织学形态与发生于脑室的中枢神经细胞瘤相似,表现为肿瘤弥漫浸润性生长,肿瘤细胞形态较一致,胞核圆形,可见神经毡背景和"树枝"状薄壁毛细血管。应注意与垂体腺瘤、少突胶质细胞瘤和透明细胞型室管膜瘤等相鉴别。     

原发性甲状腺功能减退症继发垂体增生伴高泌乳素血症

目的报告1例原发性甲状腺功能减退症继发垂体增生伴高泌乳素血症患者,探讨其组织形态学、免疫组织化学表型、诊断与鉴别诊断、治疗及预后等临床病理学特点。方法与结果女性患者,29岁,临床表现为月经失调1年,溢乳3个月,头痛1周。MRI提示垂体瘤可能性大。遂行经鼻蝶鞍区占位性病变探查术。组织学形态观察,部分腺泡细胞明显增生,呈局灶性结节状。免疫组织化学染色,增生的腺泡细胞弥漫性表达突触素、促甲状腺激素,部分表达催乳素,不表达甲状腺转录因子-1,淋巴细胞散在表达白细胞共同抗原,Ki-67抗原标记指数约1%。病理诊断为垂体增生,最终临床诊断为甲状腺功能减退症。持续服用左甲状腺素钠(优甲乐)100μg/d,随访13个月,一般状况良好。结论垂体增生诊断困难,明确诊断须依靠临床病史、组织学形态特征和免疫组织化学表型,应注意与垂体腺瘤尤其是垂体微腺瘤相鉴别。     

鞍区碰撞瘤

目的报道1例垂体腺瘤合并恶性蝾螈瘤的鞍区碰撞瘤患者,结合相关文献,总结其临床病理学特征、诊断与鉴别诊断、治疗及预后。方法与结果男性患者,59岁,因双眼视力下降、视野缺损伴头晕首次入院,头部MRI显示鞍区占位性病变。遂行鼻内镜下经鼻蝶入路垂体腺瘤切除术,手术部分切除肿瘤。术后3个月患者出现视力下降至失明伴头痛再次入院,头部CT显示鞍区和鞍上占位性病变,遂行开颅鞍区和鞍上肿瘤切除术。两次手术标本组织学形态观察,肿瘤组织由呈巢团状和梁索状排列的上皮细胞和弥漫性分布的梭形细胞组成,两种肿瘤成分单独或交错分布,首次手术标本中梭形细胞形态温和,核分裂象罕见,再次手术标本中梭形细胞密度增加,胞核深染,核分裂象易见,可见散在分布的胞质红染的横纹肌样分化。免疫组织化学染色,垂体腺瘤成分(上皮细胞区域)细胞角蛋白8、嗜铬素A、突触素和促甲状腺激素呈阳性,恶性蝾螈瘤成分(梭形细胞区域)CD56、CD57、钙视网膜蛋白呈阳性,S-100蛋白、结蛋白和肌细胞生成蛋白呈局灶性阳性。超微结构观察,垂体腺瘤区域胞质中粗面内质网丰富,可见圆形分泌颗粒,梭形细胞胞膜外缘可见不连续基膜。最终病理学诊断为鞍区碰撞瘤(无功能性促甲状腺激素腺瘤合并恶性蝾螈瘤)。患者再次手术后6个月死亡。结论垂体腺瘤合并恶性蝾螈瘤的鞍区碰撞瘤极为罕见,术前临床表现和影像学检查难以明确诊断,仍依靠对充分取材的手术标本进行组织学形态、免疫组织化学染色和超微结构观察。含有恶性蝾螈瘤成分的鞍区碰撞瘤预后较差。     

少见的鞍区混合性神经节细胞瘤-垂体腺瘤

研究背景发生于垂体的混合性神经节细胞瘤-垂体腺瘤临床罕见,由于其缺乏特征性影像学表现,易误诊为垂体腺瘤,是术前诊断鞍区肿瘤的难点。本文回顾分析1例鞍区混合性神经节细胞瘤-生长激素垂体腺瘤患者的诊断与治疗经过,结合文献对此类临床少见垂体肿瘤的临床病理学特征进行分析,以期提高诊断与鉴别诊断能力。方法与结果女性患者,28岁,临床主要表现为反复头痛伴视物模糊8月余,以及肢端肥大和闭经表现。头部CT和MRI显示鞍内和鞍上不规则占位性病变,呈T1WI等或稍低信号、T2WI稍高信号,增强扫描病灶呈明显不均匀强化,边界清晰,压迫视交叉和第三脑室底部。手术全切除肿瘤。组织学形态观察,肿瘤组织分为两部分结构,一部分为不规则簇状排列的神经节细胞样细胞分布于神经纤维背景中,另一部分为片状排列或局部乳头状结构的圆形和卵圆形细胞,两部分结构相互混杂。免疫组织化学染色,神经节细胞样细胞区域肿瘤细胞胞质突触素(Syn)呈弥漫性强阳性,腺垂体激素呈阴性;圆形细胞区域肿瘤细胞胞质Syn呈弥漫性阳性,约30%肿瘤细胞生长激素呈阳性,其余神经垂体激素呈阴性。最终病理诊断为(鞍区)混合性神经节细胞瘤-生长激素垂体腺瘤(WHOⅠ级)。术后未予放射治疗,随访1年,临床症状明显改善,肿瘤未复发。结论鞍区混合性神经节细胞瘤-垂体腺瘤临床罕见,鉴于目前大多支持该肿瘤是起源于垂体干/祖细胞、具有内分泌细胞和神经元双向分化的独立肿瘤实体,故建议采用"伴神经节细胞分化的垂体腺瘤"的诊断术语,应注意与两种独立肿瘤形成的碰撞瘤相鉴别。     

脑转移性混合性腺神经内分泌癌

目的报告首例脑转移性混合性腺神经内分泌癌的临床病理学特征,探讨诊断与鉴别诊断要点和预后影响因素。方法与结果男性患者,35岁。临床表现为头痛、呕吐,CT显示右侧颞叶占位性病变。术中可见肿瘤直径约3 cm,边界欠清晰,质地软韧,血供丰富。肿瘤由大小较一致的小圆形细胞构成,局部肿瘤细胞围绕小血管形成"菊形团"样或乳头样结构,核分裂象活跃,与周围脑组织界限不清;肿瘤细胞弥漫性表达突触素和CD56,不表达胶质纤维酸性蛋白、广谱细胞角蛋白、CD3、CD20、波形蛋白、白细胞共同抗原、甲状腺转录因子-1、S-100蛋白、神经微丝蛋白、巢蛋白、细胞角蛋白(CK)5/6、CK8/18和CD99,Ki-67抗原标记指数约为62%。外院行乙状结肠肠镜检查发现肿物,组织学呈明显双相性,由大小一致的小圆形细胞和低至中度分化的腺癌细胞构成,二者界限清晰,无移行。小圆形肿瘤细胞弥漫性表达突触素和CD56,不表达广谱细胞角蛋白;腺癌细胞弥漫性表达广谱细胞角蛋白,不表达突触素和CD56。结论混合性腺神经内分泌癌为2010年世界卫生组织命名和定义的肿瘤,发生脑转移者尚未见诸报道,明确诊断需依靠临床病史、组织形态学特征和免疫组织化学表型。     

颅内转移性恶性黑色素瘤：一例报告并文献复习

目的探讨颅内转移性恶性黑色素瘤临床组织病理学及免疫组织化学特征。方法应用组织病理学及免疫组织化学检测方法对1例颅内多发转移性恶性黑色素瘤患者的两次手术标本进行观察,通过复习文献分析其组织病理学和免疫组织化学特征,提出诊断与鉴别诊断要点。结果男性患者,48岁。因颅内多发占位性病变、肿瘤卒中而行右侧额颞叶肿瘤切除术。两次手术标本组织病理学表现不一：首次右侧额叶病灶表现为异型性上皮样肿瘤细胞围绕毛细血管和纤维组织呈乳头状排列;再次手术标本为右侧颞叶,病灶表现为梭形细胞呈片巢状或束状排列,胞质丰富、淡染或透亮,胞核异型性明显、核仁呈明显嗜酸性。左侧腹股沟淋巴结活检提示肿瘤转移,且肿瘤组织局部可见大量黑色素颗粒。免疫组织化学染色肿瘤细胞弥漫表达S一100蛋白、人黑色素细胞瘤抗原45、Melan—A和波形蛋白,部分表达上皮膜抗原,而细胞角蛋白、高分子角蛋白、低分子角蛋白、胶质纤维酸性蛋白、突触素、神经微丝蛋白等表达阴性。结论颅内转移性恶性黑色素瘤的组织学表现复杂多样,临床病史和影像学资料对诊断具有重要参考价值,但明确诊断仍需依靠免疫组织化学检测结果。需注意与转移癌、脑膜肿瘤、淋巴瘤及其他含黑色素的颅内肿瘤相鉴别。     

颅内转移性恶性黑色素瘤:一例报告并文献复习

目的探讨颅内转移性恶性黑色素瘤临床组织病理学及免疫组织化学特征。方法应用组织病理学及免疫组织化学检测方法对1例颅内多发转移性恶性黑色素瘤患者的两次手术标本进行观察,通过复习文献分析其组织病理学和免疫组织化学特征,提出诊断与鉴别诊断要点。结果男性患者,48岁。因颅内多发占位性病变、肿瘤卒中而行右侧额颞叶肿瘤切除术。两次手术标本组织病理学表现不一:首次右侧额叶病灶表现为异型性上皮样肿瘤细胞围绕毛细血管和纤维组织呈乳头状排列;再次手术标本为右侧颞叶,病灶表现为梭形细胞呈片巢状或束状排列,胞质丰富、淡染或透亮,胞核异型性明显、核仁呈明显嗜酸性。左侧腹股沟淋巴结活检提示肿瘤转移,且肿瘤组织局部可见大量黑色素颗粒。免疫组织化学染色肿瘤细胞弥漫表达S-100蛋白、人黑色素细胞瘤抗原45、Melan-A和波形蛋白,部分表达上皮膜抗原,而细胞角蛋白、高分子角蛋白、低分子角蛋白、胶质纤维酸性蛋白、突触素、神经微丝蛋白等表达阴性。结论颅内转移性恶性黑色素瘤的组织学表现复杂多样,临床病史和影像学资料对诊断具有重要参考价值,但明确诊断仍需依靠免疫组织化学检测结果。需注意与转移癌、脑膜肿瘤、淋巴瘤及其他含黑色素的颅内肿瘤相鉴别。     

Immunohistochemistry of folliculo-stellate cells in normal human adenohypophyses and in pituitary adenomas

Summary Presence and distribution of S-100 protein (S-100), neuron-specific enolase (NSE), cytokeratin polypeptides, glial fibrillary acidic protein (GFAP), vimentin, actin, lysozyme and pituitary hormones (prolactin, hGH, ACTH, -FSH, -LH, -TSH, alpha subunit) in folliculo-stellate cells (FSC) were studied in seven normal human pituitary glands and 28 pituitary adenomas using peroxidase-antiperoxidase and the avidin-biotin immunohistochemical techniques. Approximately 5% of the cells of the adenohypophysis were agranular, non-hormon-producing FSC most of which showed a conspicuous and strong reaction with S-100 antibodies but some were, in addition, GFAP- and vimentin-positive. In contrast to endocrine cells (EC), FSC were not decorated by antibodies to NSE or cytokeratins. In addition to supportive functions, these cells, due to their close special relationship to EC, seem to have transport and other metabolic functions yet to be elucidated. By their S-100 reactivity and their distribution FSC are comparable to glial cells of the central and schwann and satellite cells of the peripheral nervous system (PNS) as well as to supportive cells in neuroendocrine organs and related tumors (e.g., pheochromocytomas, paragangliomas, carcinoids). With one exception, S-100 reactive FSC were not found in pituitary adenomas. The immunohistochemical demonstration of S-100 protein in pituitary tissue is, therefore, a reliable aid in the discrimination between adenomas and normal pituitary tissue, particularly in small and poorly preserved specimens. In one adenoma FSC were found in addition to ACTH-producing tumor cells. This seems to be an extremely rare event suggesting a combination tumor.Supported in part by Fonds zur Förderung der wissenschaftlichen Forschung (no. 4708) to H. Denk     

T cell lymphoblastic lymphoma/leukemia within an adrenocorticotropic hormone and thyroid stimulating hormone positive pituitary adenoma: A cytohistological correlation emphasizing importance of intra‐operative squash smear

We present a rare case of primary pituitary T cell lymphoma/leukemia (T‐LBL) in association with adrenocorticotropic hormone (ACTH) and thyroid stimulating hormone (TSH) expressing pituitary adenoma in a 55‐year‐old woman highlighting the importance of intra‐operative squash smears examination. The patient presented with complaints of headache, diminution of vision and recent onset altered sensorium. MRI revealed a mass lesion in the sellar‐suprasellar region with non‐visualization of pituitary gland separately, extending to involve adjacent structures diagnosed as invasive pituitary macroadenoma. Intra‐operative tissue was sent for squash smear examination. The cytology showed a tumor comprising of sheets of immature lymphoid cells intermixed with clusters of pituitary acinar cells with many mitoses and tingible body macrophages. A diagnosis of presence of immature lymphoid cells within the pituitary was offered and differentials of infiltration by lymphoma cells from systemic disease versus primary central nervous lymphoma‐like lymphoma arising in the pituitary adenoma were considered. Later paraffin section examination and immunohistochemistry corroborated with the squash findings and a final diagnosis of primary pituitary T cell lymphoma/leukemia in association with ACTH and TSH expressing pituitary adenoma was made. To date, only six cases of primary pituitary T cell lymphomas, including three T‐LBL cases, have been reported. This is the seventh case and first one additionally describing cytohistological correlation and importance of intra‐operative cytology.     

Proliferating potential of folliculo-stellate cells in human pituitary adenomas

Summary Folliculo-stellate cells (FS cells) in 40 pituitary adenomas and portions of anterior pituitary adjacent to the tumor in 26 cases were investigated immunohistochemically, using polyclonal antisera to S-100 protein (S-100) and glial fibrillary acidic protein (GFAP). The objective was to clarify the histological behavior of the FS cells.In most pituitary adenomas there were few or no S-100-or GFAP-positive cell, in comparison with numerous positive cells in the parts of the adenohypophyses compressed by adenomas. However, positive FS cells were observed in some types of pituitary adenomas. Growth hormone and prolactin producing adenomas frequently contained significant amounts of FS cells. In non-functioning adenomas, an unique case of FS cell adenoma was present. The adenoma was composed mainly of FS cells and immature glandular cells. The FS cells were sometimes located around follicles containing Periodic acid Schiff-positive material. Therefore, the FS cell adenoma is characterized by S-100- and GFAP-positive FS cells and PAS-positive follicles. In this type of adenoma, FS cells seemed to be the main proliferating component.In parts of the adenohypophyses adjacent to the adenomas, GFAP0-positive FS cells were numerous. In the pathological conditions FS cells may possess the potential of reactive proliferation.     

上皮样恶性外周神经鞘膜瘤淋巴结转移临床病理学特征:病例报告及文献复习

研究背景间叶性恶性肿瘤的转移途径以血行转移为主,而上皮性恶性肿瘤大多循淋巴管道转移,但间叶性肉瘤有时也会经淋巴管道进行转移。目的探讨上皮样恶性外周神经鞘膜瘤的临床病理学特征。方法复习1例淋巴管道转移性上皮样恶性外周神经鞘膜瘤患者临床资料,通过组织学观察、组织化学染色和免疫组织化学染色研究分析肿瘤细胞特点,并进行文献回顾。结果患者女性,42岁。临床表现为右侧腋窝4cm×4cm×3cm大小肿块伴右上臂及肩部麻木。术前影像学检查显示右侧腋窝软组织肿块影及周围多发肿大淋巴结影,考虑恶性病变。术中可见右侧腋窝多个结节状肿块,最大者约5cm×3cm×3cm大小,剖面呈灰红、灰黄色,质地坚硬,局部坏死。显微镜下观察淋巴结结构破坏,肿瘤细胞呈片状或巢状排列,可见纤细的血管纤维组织分隔,大多数肿瘤细胞呈上皮样,可见多核瘤巨细胞,核分裂象易见,部分区域间质呈黏液样变性。肿瘤细胞S-100蛋白、Sox-10蛋白、波形蛋白、Col-Ⅳ表达阳性;40%的肿瘤细胞胞核P53表达阳性;细胞角蛋白、癌胚抗原、上皮膜抗原表达阴性;Ki-67抗原标记指数>90%;网状纤维染色显示网状纤维包绕上皮细胞巢。既往曾因"右腕部肿物"行两次"肿物切除术",术后病理报告为上皮样恶性外周神经鞘膜瘤伴出血及灶性坏死,结合病史,最终诊断为右侧腋窝淋巴结转移性上皮样恶性外周神经鞘膜瘤。结论上皮样恶性外周神经鞘膜瘤主要通过血行转移,较少发生淋巴管道转移,应注意与具有相似组织学形态的肿瘤相鉴别,以免误诊或漏诊。     

Thyrotropin secreting pituitary adenoma accompanying a silent somatotropinoma

Thyroid stimulating hormone (TSH) secreting pituitary adenomas are rare tumors manifested as hyperthyroidism with goiter in the presence of elevated TSH. We present a case with pituitary adenoma secreting both TSH and growth hormone (GH) with the prominent clinical findings of hyperthyroidism but without clinical findings of acromegaly. Pituitary magnetic resonance imaging revealed a macroadenoma. Transsphenoidal surgery was performed twice. The immunohistochemical staining showed that tumor cells were strongly reactive to GH and relatively mildly reactive to TSH. Control pituitary imaging revealed a residual macroadenoma, and long acting octreotide treatment was administered. After two years of the treatment, tumor size remained the same while thyroid function tests and insulin-like growth factor 1 (IGF-I) values returned to normal ranges. In conclusion, we always recommend hormonal examinations for all patients who have pituitary adenoma without signs and symptoms of acromegaly.     

Double tumors of anterior and posterior pituitary gland

Summary Double tumors were found in the anterior and posterior lobes of pituitary gland at autopsy in a patient who presented with progressive deterioration of mental status. The chromophobe adenoma of anterior lobe consisted of a mixture of non-immunoreactive hormone containing cells and a few prolactin (PRL) and growth hormone (GH) cells in the mid portion whereas the periphery of the tumor contained immunoreactive cells for PRL, GH, thyroid-stimulating hormone (TSH), luteinizing hormone (LH), and follicle-stimulating hormone (FSH). A microscopic focus of granular cell myoblastoma (GCM) was found in the posterior lobe. Differentiation of tumor cells into anterior pituitary cells and GCM is discussed.     

间变型多形性黄色瘤型星形细胞瘤

目的报道1例男性间变型多形性黄色瘤型星形细胞瘤患儿的临床资料,探讨其临床病理学、免疫表型、基因突变特征,以及诊断与鉴别诊断要点。方法与结果男性患儿,11岁,头痛伴左上肢无力15 d。头部CT和MRI显示右侧颞叶和基底节区巨大占位性病变,提示胶质瘤。遂行右侧颞叶和基底节区占位性病变切除术,术中可见肿瘤呈囊实性,实性部分呈灰黄色,质地柔软,血供丰富,无包膜,与周围组织界限清晰。术中冰冻病理学提示低级别胶质瘤,遂分块全切除肿瘤。组织学形态观察,肿瘤细胞呈多形性,由梭形和圆形星形胶质细胞以及单核细胞和多核瘤巨细胞组成,核分裂象罕见;局部可见较成熟的神经元或节细胞分化成分,伴淋巴细胞浸润;部分区域肿瘤细胞呈间变特征,细胞密度增加,异型性明显,以圆形和梭形细胞为主,核分裂象5个/10高倍视野,血管内皮细胞增生,伴血管周围假"菊形团"样结构,局灶性坏死。免疫组织化学染色,低级别肿瘤细胞胞质表达胶质纤维酸性蛋白(GFAP)和BRAF V600E、胞质和胞核表达S-100蛋白、胞膜表达CD34,少数肿瘤细胞胞质表达突触素和非磷酸化神经丝重链SMI-32,Ki-67抗原标记指数为3%;低级别和高级别肿瘤细胞胞核均表达P53;高级别肿瘤细胞胞质表达GFAP和BRAF V600E,Ki-67抗原标记指数为30%。网织纤维染色可见肿瘤细胞周围包绕基底膜样物质。基因检测显示,低级别和高级别肿瘤均存在BRAF V600E杂合突变。结论2016年世界卫生组织中枢神经系统肿瘤分类将间变型多形性黄色瘤型星形细胞瘤定义为核分裂象5个/10高倍视野,属WHOⅢ级,预后较WHOⅡ级多形性黄色瘤型星形细胞瘤差。鉴别诊断主要包括胶质母细胞瘤、毛细胞型星形细胞瘤和节细胞胶质瘤,尽管上述肿瘤临床表现、组织学形态、免疫表型和基因突变有重叠,但生物学行为、治疗及预后各异。