延胡索酸水合酶缺陷型子宫平滑肌瘤19例临床与病理分析

Clinical and pathological analysis of 19 cases of fumarate hydratase-deficient uterine leiomyomas

目的:探讨延胡索酸缺陷型子宫平滑肌瘤(FH-DUL)的临床特征、组织形态、免疫表型和分子特点,并分析与复发风险相关的危险因素。方法:收集2019年11月至2023年4月于苏州市立医院本部诊治的19例FH-DUL,回顾分析其临床表现、组织学特征、免疫组化表型,并对其中1例行高通量二代测序(NGS法)检测。结果:19例FH-DUL患者平均年龄(38.6±8.2)岁,其中5例(26.3%)有月经量增多、下腹包块、痛经等临床症状,其余14例(73.7%)为体检发现。11例(57.9%)为多发肌瘤(≥2枚),8例(42.1%)为单发性肌瘤,最大径4~13cm。1例(5.3%)为黏膜下肌瘤,13例(68.4%)为肌壁间肌瘤,5例(26.3%)为浆膜下肌瘤。6例(31.8%)患者的一级亲属有子宫平滑肌瘤病史。13例(68.4%)行腹腔镜下子宫肌瘤剔除术,6例(31.6%)行腹腔镜下全子宫切除术。19例均具有至少一个典型的FH-DUL形态特征。低倍镜视野下:19例(100%)可见薄壁鹿角状血管,13例(68.4%)明显富于细胞,11例(57.9%)可见灶性的肺泡样水肿间质。高倍镜视野下:11例(57.9%)见奇异形核,12例(63.2%)见胞质内嗜酸性小球沉积,8例(42.1%)见显著的嗜酸性大核仁及核仁周围空晕,核分裂<5个/HPF,未见明显肿瘤性凝固性坏死。19例免疫组化均为SMA、Desmin、h-caldesmon阳性表达,FH表达完全缺失。1例行高通量测序示FH基因胚系突变阴性,可能致病变异为FH基因拷贝数缺失。19例患者随访期内复发3例(15.8%),无死亡。年龄(<35岁)、家族肿瘤史与患者术后复发率呈显著相关(P均<0.05)。结论:FH-DUL具有一定特征的组织学形态,但并不绝对。独特的病理形态联合免疫组化检查有利于FH-DUL的诊断,结合临床特征可以指导进行遗传咨询和正式的突变检测。当患者年龄<35岁、有肿瘤家族史时,需警惕其复发风险。

Objective:To investigate the clinical,histological,immunophenotypic and molecular characteristics of fumarate hydratase-deficient uterine leiomyomas(FH-DUL),and to analyze the risk factors associated with recurrence.Methods:19 cases of FH-DUL were included in this study from November 2019 to April 2023.Clinical and histological features and immunohistochemical phenotypes were retrospectively analyzed,and 1 case was detected by high-throughput second-generation sequencing(NGS).Results:The age of the 19 FH-DUL patients was 38.6±8.2 years old.5(26.3%)cases had clinical symptoms,such as increased menstrual flow,lower abdominal mass,and dysmenorrhea,while the other 14(73.7%)were found by physical examination.11 cases(57.9%)had multiple fibroids(≥2),and 8 cases(42.1%)had single fibroids with a maximum diameter of 4~13cm.One case(5.3%)was diagnosed as submucosal leiomyoma,13 cases(68.4%)as intramural leiomyoma,and 5 cases(26.3%)as subserosal leiomyoma.Six cases(31.8%)had a family history of uterine leiomyoma in first-degree relatives.13 cases(68.4%)underwent laparoscopic myomectomy,and 6 cases(31.6%)underwent laparoscopic total hysterectomy.Under low power view,thin-walled staghorn vessels were observed in 19 cases(100%).Significant cellular were seen in 13 cases(68.4%),and focal alveolar-like edematous stroma was seen in 11 cases(57.9%).Under high power,bizarre nuclei were seen in 11 cases(57.9%),eosinophilic glomerular deposition in the cytoplasm were found in 12 cases(63.2%),and in 8 cases(42.1%),significant eosinophilic large nucleoli and perinucleolar halos were observed,with nuclear division<5/HPF,and no obvious tumor coagulated necrosis.The immunohistochemical staining of all 19 cases showed positive expressions of SMA,Desmin,and h-caldesmon,while complete loss of FH expression was observed.1 High throughput sequencing showed negative FH gene mutation in the germ line,which may result in the deletion of FH gene copy number.During the follow-up period,3 patients(15.8%)relapsed,and no death occurred.Age(<35 years old)and family tumor history were significantly correlated with postoperative recurrence rate(P<0.05).Conclusion:FH-DUL has certain characteristic histological morphology,but it is not absolute.The unique pathological morphology combined with immunohistochemistry is conducive to the correct diagnosis of FH-DUL,and the combination of clinical features can guide genetic counseling and formal mutation detection.When patients are<35 years of age and have a family history of tumors,they should be alert to the risk of recurrence.