背景:原发性直肠绒毛膜癌是一种极其罕见的恶性肿瘤。尚未报道这些肿瘤在炎症性肠病(IBD)患者中的相关性。
方法:一名34岁女性,有溃疡性结肠炎(UC)病史,生下一名男性胎儿。她有产后出血,检测到高水平的β-人绒毛膜促性腺激素(βhCG)。尽管初步调查未能证实磨牙怀孕,异常子宫出血和高βhCG水平需要化疗。因此,她对化疗没有反应。同时,患者经历了直肠出血和结肠镜检查,发现距肛门边缘8-10厘米的粘膜下息肉样病变。多学科小组对患者进行全直肠结肠切除术和回肠袋肛门吻合术。尽管术后进展顺利,βhCG水平下降,但在随访中呈上升趋势。计划化疗,但没有合适的反应。不幸的是,患者在初次诊断后20个月去世.
结论:病理报告提示中分化管状腺癌和绒毛膜癌并存。我们假设先前的UC病史可能使她对癌症的易感性更高,而这种低分化的癌症导致绒毛膜癌。考虑到在大多数结直肠绒毛膜癌病例中,绒毛膜癌分化与结肠腺癌一起被发现,这使得去分化理论成为最可接受的解释。
结论:IBD背景下的结肠和直肠腺癌可能变得如此去分化,从而获得生殖细胞肿瘤的某些特征。
BACKGROUND: Primary rectal choriocarcinoma is an extremely rare malignancy. The association of these neoplasms in patients with inflammatory bowel disease (IBD) has not been reported.
METHODS: A 34-year-old female with history of Ulcerative Colitis (UC) gave birth to a male fetus. She had postpartum bleeding and high level of beta-human chorionic gonadotropin (βhCG) was detected. Although initial investigations failed to confirm molar pregnancy, abnormal uterine bleeding and high βhCG level necessitate chemotherapy administration. She did not respond to chemotherapy sessions accordingly. Meanwhile, the patient experienced rectorrhagia and colonoscopy revealed a firm submucosal polypoid lesion 8-10 cm from the anal verge. The multidisciplinary team candidate the patient for total proctocolectomy and ileal pouch anal anastomosis. Although postoperative course was uneventful and βhCG level dropped but it showed a rising pattern in follow ups. Chemotherapy was planned but there was not suitable response. Unfortunately, the patient passed away 20 months after the initial diagnosis.
CONCLUSIONS: Pathology report indicated the coexistence of moderately differentiated tubular adenocarcinoma and choriocarcinoma. We assume previous history of UC might have put her at higher susceptibility to develop carcinoma and this poorly differentiated carcinoma has led to choriocarcinoma. Considering the fact that in most cases of colorectal choriocarcinoma, choriocarcinomatous differentiation was found alongside colonic adenocarcinoma made dedifferentiation theory to be the most acceptable explanation.
CONCLUSIONS: The adenocarcinoma of the colon and rectum in the setting of IBD may become so dedifferentiated that gain some characteristics of germ cell tumors.