Primitive neuroectodermal tumor of the transverse colonic mesentery defined by the presence of EWS-FLI1 chimeric mRNA in a Japanese woman

Abstract

We report a case of primitive neuroectodermal tumor (PNET) arising in the transverse colonic mesentery. A 24-year-old Japanese woman was admitted to Kagoshima City Hospital with complaints of abdominal pain and sensations of abdominal fullness of 5 months' duration. On palpation, a mass the size of an infant's head was noted in the right flank. Abdominal computed tomography (CT) and ultrasonography showed a huge mass that consisted of multiple cystic components. On arteriography, a slight tumor stain appeared, with stretched and displaced tributaries of the right colic and middle colic arteries. Barium swallow examination demonstrated that the ascending colon was shifted to the right and small intestine to the left. We performed an en-bloc resection of the tumor in the transverse colonic mesentery, including the ascending colon, proximal jejunum (20 cm in length), and greater omentum. The resected tumor was 12 x 10 x 7 cm in size, 590g in weight, elastic soft in consistency, and multicystic. Histologically, the specimens showed a sheet-like proliferation of spindle-to-polygonal cells, and focally, the tumor formed rosette structures. Immunohistochemically, the tumor cells were positive for neuron-specific enolase (NSE) and mic-2. EWS-FLI1 chimeric mRNA was detected by reverse transcriptase-polymerase chain reaction (RT-PCR). Based on the above findings, we finally diagnosed the tumor as PNET of the colonic mesentery. There has been no recurrence for 20 months after operation. PNET arising in the mesentery is very rare, and we distinguished PNET from other tumors by immunohistochemical examination and by demonstration of the presence of EWS-FLI1 chimeric mRNA in the tumor.

Primitive Neuroectodermal Tumor Arising in the Colon: Report of a Case

“…The most common sites of pPNETs are the extremities, the paravertebral region, and the chest wall, 1,2 although there are sporadic case reports of pPNETs arising in the kidneys, 12 gynecological organs, 12 pancreas, 12 omentum, 13 and the mesentery. 5 Conversely, the incidence of a pPNET in the alimentary tract is extremely rare. 12,14,15 In fact, we were able to find only one report of a pPNET occurring in the rectum, 16 based on a MEDLINE search up until June 2004.…”

“…Written informed consent was obtained from the patient and from two other patients whose gastrointestinal tumors served as a negative control. The detection of EWS-FLI1 fusion transcripts from the tumor was performed according to the method described by Tokudome et al 5 with some modifications. Briefly, the total RNA of each resected specimen was a b c d …”

Ewing's Sarcoma Family of Tumors: Current Management

“…Individual members of this tumor family are defined along a gradient of limited neuroglial differentiation, with the poorly differentiated Ewing's sarcoma at one end and the more mature pPNETs at the other. With the availability of molecular tools to unambiguously confirm the presence of ews-ets gene rearrangements, the spectrum of Ewing's sarcoma-related neoplasms has recently been expanded to include rare CD99 MIC2 -positive extraskeletal tumors in various anatomic sites including the kidney [40][41][42][43][44], breast [41], gastrointestinal tract [45][46][47][48], prostate [49], endometrium [50], lung [44], adrenal gland [51], and meninges [52]. Although Ewing's family of tumors typically arise during adolescence, there is also an increasing number of adults being diagnosed with a CD99…”

Peripheral primitive neuroectodermal tumour of the chest wall invading lung with regional lymph node metastasis

“…Although these characteristics can be established in most cases using the small samples obtained by needle biopsy, diagnosis may be difficult in others because of many differential diagnostic possibilities [5]. Detection of EWS/FLI-1 fusion gene transcripts has recently become a useful tool for the diagnosis of pPNET/ES [1,2].…”

“…Prior to testing for EWS/FLI-1 chimeric mRNA in the tumour, written informed consent was obtained from the patient under the approval of the local ethics committee. According to Tokudome et al [5], the EWS/FLI-1 fusion transcript was found to be expressed in the tumour (Fig. 2D).…”