A case of congenital infantile fibrosarcoma of sigmoid colon manifesting as pneumoperitoneum in a newborn

Abstract

Congenital infantile fibrosarcoma (CIF) is a rare soft-tissue tumor in the pediatric age group and seldom involves the gastrointestinal tract. A 2-day-old boy was transferred to our hospital with a pneumpoperitoneum. After emergency operation, we could find a solid mass wrapping around a sigmoid colon and performed a segmental resection of sigmoid colon including a mass. Histopathologic examination showed an infantile fibrosarcoma origining from the muscular layer of colon. The baby was discharged on the 17th hospital day and followed for 1 yr without recurrence.

Keywords: Congenital Infantile Fibrosarcoma (CIF); Gastrointestinal.

Fig. 1

Infantography shows a large amount of free-air in peritoneal cavity before operation.

Fig. 2

Grossly it shows a round mass wrapping around a sigmoid colon.

Fig. 3

A hypercellular and poorly circumscribed tumor mass in submucosa and muscularis proper (H&E stain, × 40), atypical spindle cells forming fascicular arrangement with mitoses and small amount of interstitial collagen in inlet (H&E stain, × 400).

Fig. 4

Immunohistochemical stains of tumor cells. Positive for vimentin and smmoth muscle actin (SMA, × 200) in A, Ki-67 proliferation index 20% in B, negative for desmin (desmin, × 200) and h-caldesmon (h-caldesmon, × 200) in C, D.

Fig. 5

Follow-up PET-CT shows no abnormal uptakes, evidence of tumor recurrence, 12 months later after operation.