The present case report describes a rare case of epidermoid cyst of the cecum treated by SILS ileocecal resection.
Cecal epidermoid cyst is extremely rare, with only 9 other cases reported in the English literature [3]. Epidermoid cyst is considered to represent a sequestered cyst with a congenital or acquired origin. Congenital epidermoid cyst is attributed to inclusion of ectodermal tissue when epithelial surfaces coalesce. Conversely, acquired epidermoid cyst is thought to develop in patients with chronic inflammation or a history of abdominal trauma and might be due to implantation of epidermis in a location favorable to growth [1]. Park et al. reported 9 cases of cecum epidermoid cyst, of which 3 cases (33.3%) involved a history of abdominal surgery [3]. We speculate that the present case involved congenital epidermoid cyst, because the patient had no history of abdominal surgery, trauma, or chronic inflammation and was aware of right lower quadrant pain for a long period of time.
Preoperative diagnosis of cecal epidermoid cyst is difficult, and no previous reports have described reach accurate preoperative diagnosis. On CT, epidermoid cyst appears as a well-demarcated, low-density mass with enhancement of the capsule following contrast administration [11]. On MRI, the tumor appears hypointense on T1-weighted imaging and hyperintense on T2-weighted imaging. However, these findings are not specific to epidermoid cyst. The cyst may also be confused with GIST and other intra-abdominal cystic lesions such as lymphatic cyst, appendiceal mucocele, mesenteric cyst, or duplication cyst [2, 12]. In the present case, CT showed a cystic mass with no enhancement and MRI revealed a T1-hyperintense, T2-hypointense mass with features similar to previous reports of epidermoid cyst. However, we suspected GIST or duplication cyst preoperatively.
Epidermoid cyst needs to be treated by complete removal of the tumor. One reason is that residual tissue and cyst wall may lead to recurrence [5]. The recurrence rate has been reported as 2% [5]. Another reason is that occasional cases have malignant potential [13]. Yang et al. revealed malignant potential in one of 60 patients (1.7%) with epidermoid cyst. A review of the Japanese literature showed that among 101 patients with presacral epidermoid cyst, six cases had squamous cell carcinoma in the cyst wall [13]. In the present case, preoperative diagnosis was difficult and we performed ileocecal resection for complete resection as in cases of malignancy.
Laparoscopic surgery has recently gained popularity as an approach to colon disease, due to better short-term outcomes including reduced blood loss, better recovery of bowel function, and shorter duration of hospitalization [6]. Epidermoid cyst of the cecum is considered to meet the indications for laparoscopic surgery as a basically benign tumor. In the English literature for cecal epidermoid cysts, only one recent case was treated by laparoscopic surgery, and the laparoscopic approach was described as beneficial for both diagnosis and treatment [12].
Several randomized controlled studies have shown that SILS offers a feasible method with better short-term outcomes compared to conventional laparoscopic surgery [8, 14,15,16]. However, SILS remains technically challenging due to the in-line view, instrument crowding, and loss of triangulation necessitating a high level of technical competence [14, 17]. Basically, we have to select safer procedures such as conventional laparoscopic surgery or SILS plus one port surgery when the tumor shows malignant potential. We previously performed SILS using an organ retractor to overcome the restrictions related to single-port surgery (18). This instrument can grasp and release in various positions to provide an adequate view, which could be instructive for non-expert surgeons when considering how to create a better surgical view, as in the case of SILS with an additional port. In the present case, the tumor was able to be completely resected using this procedure. However, we have to carefully consider the indications if patients display several factors that prevent performance of an SILS approach, such as bulky tumor, severe obesity, or severe adhesions, and a safer approach must be selected.
