Case Report: a Case of Jejunal Mesenteric Teratoma in Adult Male: a Rare Case

Introduction

Teratoma comes from two Greek words, teraton meaning (monster) and onkoma (swelling). This name was first given by Rudolph Virchow in 1869 due to diversity of the anatomical component in the sacrococcygeal type. It arises early in embryonic cell division from totipotent cells, by definition it should contain all three germ cell layers: ectoderm, endoderm, and mesoderm; however, majority of pathologists do not require the presence of cells from these germinal layers. The best current definition nowadays is the one given by Willis, “teratomas is a tumor or neoplasm formed of several foreign tissues arising in abnormal location, this is different from cases which contain recognizable organs immaturely developed within the mass, as a result of separation from the fertilized ovum early in pregnancy called fetus in feto.” [1]

Some teratomas are entirely benign, some are all malignant, and others may contain a mixture of benign and malignant tissues. Benign type is the most common one and malignant transformation may rarely occur, and it has been reported to be between 1 and 12.5% for sacrococcygeal lesions [2]. The most common malignancies arising in teratomas are squamous cell carcinoma, carcinoid tumor, and adenocarcinoma [3]. Teratomas commonly arise in the gonads and sacrococcygeal region, followed by the mediastinum, stomach, liver, and retroperitoneal space [3]. Clinically, teratomas are presented as a mass noticed during clinical examination or mass effect symptoms related to pressure on the adjacent structure, hematemesis, melena, and secondary anemia, and could be the presenting features of gastric teratomas. Symptoms due to malignant invasion of the adjacent structures may also occur.

The cystic mature teratoma develops from pluripotential cells of embryonic remnants of the ectodermal lines and usually contains a combination of both cystic and solid elements, including hair, teeth, cartilage, and dermal appendages such as hair follicles, sweat glands, and sebaceous material. This tumor is commonly found in the ovary, but may occur in any theoretical pathway of ectodermal cell migration, mostly in the midline, from the cranium, mediastinum, and retro peritoneum to sacrococcygeal regions [4]. It occurs almost exclusively in the very young [5]^.

A mature mesenteric teratoma is very rare in an adult male. So, it is not usually included in the differential diagnosis for an adult male presenting with abdominal lump. A plain abdominal radiograph demonstrates teeth and bone; thus, it gives more than an idea that the tumor is a teratoma.

Teratomas in the gastrointestinal tract are rare. Teratomas are usually found in the sacrococcygeal area (47.2%), in the gonads (31.6%), and less frequently at other sites and rarely in the mesentery [6]. There are few case reports in the literature; this should be one of the differentials for cystic lesion in abdomen. Here, we describe a case of mature mesenteric teratoma in adult male.

Case Report

A 33-year-old male presented with painless lump in the left side, present since birth, gradually increasing in size. H/O pain abdomen is since 1 year of age. There is no history of vomiting, fever, and weight loss. On abdominal examination, there is palpable mass in the abdomen of a size 8 × 8 cm in the RT side (hypochondrium, lumbar, umbilicus region). Swelling had restricted transverse mobility, and external genitalia was normal on examination. Ultrasonography revealed normal except grade 1 fatty liver. CECT abdomen showed a well-defined non-enhancing heterogeneous lesion with a size 10.7 × 7 × 10.2 cm (AP × TR × CC) with solid and fat contents within the mesentery in the sub-hepatic region with multiple specks of coarse calcifications within mesenteric teratoma. US-guided FNAC shows features are compatible with the radiologic impression of teratoma (CT did not have definitive features of teratoma and so had suspicion of gist and to rule out this, if it was gist as it looked locally advanced on CT scan) (Fig. 1). Tumor markers were not done (as it was intraabdominal mass with suspicion of teratoma/gist). The patient was explored with midline incision; intraoperatively, a mass of size 8 × 10 was seen imbedded in a mesentery of jejunum with adhesions to adjacent bowel (jejunum) (Fig. 2). The mass had cystic and bony hard areas. Complete excision of mass was done with resection of segment of jejunum and end-to-end anastomosis. Post-op events went well and the patient was discharged.

Fig. 1.

CT images showing mass lesion arising from the small intestine mesentry

Fig. 2.

Intraoperative: mass arise from the jejunal mesentry

Discussion

Teratoma is commonly a germ cell tumor originating from the gonads and seen in the female reproductive age group. During development, germ cell migrates from the yolk sac to the genital ridge, through the hind gut (route of mesentery). This explains development in abnormal location like mesentery.

The clinical presentation is usually non-specific. It depends on the size and location of the growth. Compression on bladder and small bowel can cause abdominal discomfort and pain in the lower quadrant. A hard lump is felt on palpation.

Diagnosis is confirmed by radiological modalities and examination of the histological specimen. Radiograph of abdomen shows teeth and bones, suggestive of teratoma (Fig. 3). On ultrasound, the diagnosis of teratoma should be suspected if a cystic mass is detected with fat fluid level and acoustic enhancement of calcification. CT scan characterized mature mesenteric cystic teratoma as a predominantly fatty mass with denser dependent elements and globular foci of calcification in a solid protuberance projecting into the cyst cavity. Calcifications are commonly seen in the solid component or in the wall. On MRI, cystic teratomas reveal the signal characteristic of fat (hyperintense on T1-weighted images) and water (hypointense on T1-weighted images and hyperintense on T2-weighted images). They are primarily benign with rare conversion to malignancy [7–8]^.

Fig. 3.

Cut section of specimen shows hair and teeth

Pathologically, a cystic mesenteric teratoma contains both cystic as well as solid components [7, 9]. In summary, as mesenteric teratoma is a benign neoplasm. It is important to establish the preoperative diagnosis by radiological studies. As they are well encapsulated without invagination into surrounding structures, surgical excision is the best modality of treatment.

Eghty-five cases of teratomas were reported from Riley Children’s Health, Indian University Health, Indianapolis, USA, in which 27 (32%) were boys 58 and (68%) were girls. Teratoma was arising from sacrococcygeal in 55 (64.8%) patients, gonadal in ten (11.7%), mediastinal in ten (11.7%), presacral in four (4.8%), retroperitoneal in three (3.5%), and cervical in three (3.5%) [10].

Mesenteric cysts are rare pathologic entities, with a reported incidence of approximately 1 of 27,000 to 1 of 100,000 admissions. Florentine anatomist Benevieni first described a mesenteric cyst in 1507, while performing an autopsy on an 8-year-old boy [11]. Teratomas are germ cell tumors composed of multiple cell types derived from one or more of the three germ layers. Most commonly teratoma occurs in the early age group [12]. Mature mesenteric teratoma in adulthood is extremely rare [13].

The incidence of malignancy is reported to be less than 3% [14]. To exclude malignant potential, performing complete surgical excision and a full histological examination of the resected specimen are recommended [15]. Mesenteric cysts can be treated with either laparotomy or laparoscopic surgery. The selection of the surgical approach depends on the size of the cyst, the location within the abdominal cavity, and the skill of the surgeon.

Conclusion

Abdominal teratoma is rare and should be taken into consideration as one of the differential diagnosis of abdominal mass; it is usually benign. Total excision is the mainstay of treatment. Careful histopathological examination and close follow-up is mandatory.