Mady Hussam H, Melhem Mona F
Department of Pathology, University of Pittsburgh Medical Center and the Veterans' Administration Healthcare System, Pittsburgh, PA 15240, USA.
Int J Colorectal Dis. 2002 Jul;17(4):280-3. doi: 10.1007/s00384-001-0386-z. Epub 2002 Feb 13.
Pure, benign epidermoid cysts of the abdominal viscera are rare. There have been only four reports of epidermoid cysts of the cecum in the literature, two following appendectomies and attributed to the surgical procedure, and two in female patients, raising the possibility of dermoid cysts related to the ovaries.
We report the first case of epidermoid cyst of the cecum in an elderly man with no previous history of trauma or surgery, detected by computed tomography as an incidental finding of extraluminal cystic cecal mass. It was treated by partial colectomy. Pathologically the cyst was roughly spherical, extending from and expanding the serosal surface of the cecum with no communication through the muscularis wall. Histologically the inner lining of the cyst was composed of benign, mature, keratinized, stratified squamous epithelium with a well formed granular layer. No calcification, hair, teeth, or bone elements was detected.
The interesting finding in our case is the unusual anatomical location and the age and sex of the patient. The patient had no history of any abdominal surgical procedures. The most likely explanation for the presence and development of an epidermoid cyst in this location is the result of an aberrant ectodermal implantation during embryogenesis.
Awareness of the possibility of the presence of epidermoid cysts in this area with distinctive radiological findings consistent with a well circumscribed benign cyst should be considered in the differential diagnosis of cysts within the abdomen.
腹腔脏器的单纯性良性表皮样囊肿较为罕见。文献中仅有4例关于盲肠表皮样囊肿的报道,其中2例发生于阑尾切除术后,归因于手术操作,另外2例见于女性患者,提示可能与卵巢皮样囊肿有关。
我们报告了首例盲肠表皮样囊肿病例,患者为老年男性,既往无创伤或手术史,通过计算机断层扫描偶然发现为盲肠腔外囊性肿物。经部分结肠切除术治疗。病理检查囊肿大致呈球形,起源于盲肠浆膜面并使其扩张,未穿过肌层壁相通。组织学检查囊肿内衬为良性、成熟、角化的复层鳞状上皮,有完整的颗粒层。未检测到钙化、毛发、牙齿或骨成分。
我们病例中的有趣发现是其不寻常的解剖位置以及患者的年龄和性别。患者无任何腹部手术史。该部位表皮样囊肿存在和发展的最可能解释是胚胎发育过程中异常的外胚层植入。
在腹部囊肿的鉴别诊断中,应考虑到该区域存在表皮样囊肿的可能性,其具有与边界清晰的良性囊肿一致的独特影像学表现。