Endodermal sinus tumor of testis with acute intestinal obstruction: A rare presentation.

A 7-year-old boy reported with endodermal sinus tumor of left testis, jejunal metastasis and intestinal obstruction. He was treated by high inguinal orchidectomy and resection of jejunal mass followed by chemotherapy.

INTRODUCTION

Pediatric germ cell tumors are rare and they account for 3-4% of childhood solid tumors.[1] Endodermal sinus tumor (EST) is the most common testicular neoplasm in the pediatric population and accounts for approximately half of the prepubertal testis tumors.[2-4] ESTs in all locations are highly malignant and metastasize to lymph nodes, lung, liver and bone. In adults, the clinical course is poor.[56] Herein, we report an unusual case of metastasis of testicular tumor to the small bowel and its management.

CASE REPORT

A 7-year-old boy was admitted with a history of colicky pain in the abdomen and bilious vomiting for last 2 days. He was dehydrated with abdominal distension and visible peristalsis. The patient was stabilized first with adequate resuscitative measures. The left testis was enlarged (6 cm × 4 cm) and nontender. Right testis was normal. The blood counts were normal. The serum alpha fetoprotein (AFP) level was 756 IU/ml. Plain radiograph of the abdomen revealed multiple air-fluid levels. An ultrasonography of the testis showed a heterogeneous mass arising from the left testis.

On exploratory laparotomy, a mass was noted arising from the jejunum. The mass was completely occluding the jejunal lumen [Figure 1]. The mass measured 5 cm × 5 cm in the jejunum and was about 2.5 feet away from the duodenojejunal flexure. Resection of jejunum with adequate margins, end-to-end anastomosis, biopsy of mesenteric and retroperitoneal lymph nodes and high inguinal left orchidectomy were performed. The postoperative period was uneventful. The patient was discharged on 6th postoperative day. The histology of the resected jejunum showed reticular and endodermal sinus patterns with Schiller Duval bodies [Figure 2]. The resection margins of the intestine were tumor free. The mesenteric and retroperitoneal lymph nodes showed features of reactive hyperplasia. Both the intestine and testis were periodic acid-Schiff (PAS) positive as well immunoreactive for AFP [Figure 3]. The patient received six cycles of chemotherapy with Cisplatinum (1.3 mg/kg/dose), Etoposide (3 mg/kg/dose) and Bleomycin (15 units/m2). After six cycles of chemotherapy, the patient had ultrasonography of the whole abdomen and serum AFP, and both were normal. The patient is doing well, though the follow-up is only for 10 months.

Figure 1

The left picture shows the resected jejunum with metastases at two sites and the right picture shows cut open specimen

Figure 2

The left picture shows the cut open specimen of the testicular tumor and the right picture shows photomicrograph of endodermal sinus tumor with Schiller Duval bodies (×400)

Figure 3

Photomicrograph of immunohistochemistry showing positive for AFP (×400)

DISCUSSION

About 80% of pediatric ESTs present with stage I disease,[2367] but our patient presented atypically with intestinal metastases (Stage IV disease). Childhood EST does not appear to be associated with cryptorchidism.[8] Besides baseline investigations, all patients of testicular tumors should have ultrasonography of testis and abdomen, computed axial tomography of abdomen, chest X-ray and estimation of serum AFP. Testicular tumors are treated with radical inguinal orchidectomy and multi-agent chemotherapy.[910]

EST is a highly malignant neoplasm of germ cells, which grows rapidly and metastasizes early via the lymphatic and hematogenous routes. The pattern of metastatic disease of yolk sac tumors in childhood differs from the pattern in adult germ cell tumors, owing to a higher incidence of hematogenous spread.[11] Approximately 95% of yolk sac tumors are confined to the testis. The lungs are the most common site of distant metastasis, which are affected in 20% of patients. Metastasis of yolk sac tumors to the retroperitoneum is uncommon in children (4–6%), whereas in adults, spread is usually to the retroperitoneal nodes. The tumor tends to metastasize to retroperitoneal lymph nodes below renal vessels first because of the anatomy of lymphatic flow from testis. It also frequently causes hematogenous spread. Abnormal sites of testicular metastasis are liver, brain, bone, bowel, spinal cord, cauda equina and eye.[811-14] The most commonly observed metastatic sites of the gastrointestinal (GI) tract include the small intestine and duodenum.[1415]

In a review article by Grady et al., 33 patients presented with metastatic disease. Nine patients had retroperitoneal metastases, 13 had hematogenous spread alone, lymphatic and haematogenous spread was seen in 6 patients and the sites could not be clearly documented in 5 patients.[16] This study shows a hematogenous predilection in the spread of metastases and suggests that retroperitoneal lymph node dissection has no routine value in the treatment of children with yolk sac tumor of the testis.

CONCLUSION

Our case presented with features of acute intestinal obstruction due to metastasis to small bowel, which is a very rare presentation and so should be kept in mind in the differential diagnosis when a patient of testicular tumor presents with acute abdomen. The survival has increased significantly in the last two decades. Improvements in outcome are related to the use of multi-agent chemotherapy and to a better understanding of tumor biology.[8]