Radiological features of primitive neuroectodermal tumors in intra-abdominal and retroperitoneal regions: A series of 18 cases

Abstract

ObjectivesTo characterize the imaging and clinicopathological features of primitive neuroectodermal tumors (PNETs) arising in intra-abdominal and retroperitoneal regions.MethodsEighteen patients with histopathologically proven intra-abdominal and retroperitoneal PNET were enrolled; computed tomography was performed for all cases, and magnetic resonance imaging was performed for a single case. Typical computed tomography and magnetic resonance imaging findings, including morphology, texture and enhancement features, as well as clinicopathological characteristics and prognosis data were retrospectively analyzed.ResultsOf eighteen PNET patients, fifteen were male and three were female, with a median age of 36 years (range, 2–65 years). The onset of symptoms was most often nonspecific and insidious. The mean tumor diameter was 7.2 cm (range, 3.0–12.1 cm), with necrosis in fifteen cases, cystic changes in eight, partition structure in five, calcification in five, hemorrhage in two, and mural nodules in one. Contrast enhanced computed tomography showed multiple tiny feeding arteries within the masses in six cases, resulting in a crab-like appearance, and mild ring enhancement pattern in five cases. Eleven cases showed surrounding invasion and metastasis. Of the eighteen PNET cases, nine cases showed smooth, well-defined margins, and nine cases had irregular, ill-defined margins. A median survival was 10.0±1.6 months. However, chemotherapy had efficacy on patients even those with advanced disease.ConclusionsPrimary intra-abdominal and retroperitoneal PNETs are rare, and imaging features documented here may help the diagnosis of this severe disease. Notably, two signs present in retroperitoneal PNET tumors, including a mild ring enhancement pattern and a crab-like appearance of the tiny feeding arteries, may have the potential to help us improve the ability to make a relatively reliable diagnosis.

Peripheral primitive neuroectodermal tumors: A retrospective analysis of 89�cases and literature review (Review)

“…The median age ranged from 1 (19) to 36 (25) years. A male preponderance was described in 14 studies (8,(12)(13)(14)(15)(16)(17)(20)(21)(22)(23)(24)(25)(26). Nevertheless, there were a comparable 43 males and 46 females in the present study.…”

“…Peripheral PNETs are generally large, soft tissue masses with a reported mean diameter >5 cm, as confirmed by the reviewed studies that investigated primary tumor size (11,14,16,21,22,25,26). Tumor bulk was the single most important prognostic factor, with 80% survival among patients with smaller primary tumors (<100 ml), compared with only 40% survival among those with larger tumors (>100 ml) (27).…”

“…Our review of the literature revealed 17 pPNET report series. The clinical features, treatments and outcomes of the reported patients, as well as the 89 in the present study, are summarized in Table III (8,(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26).…”

Primary Ewing sarcoma of the adrenal gland: A rare cause of abdominal mass

“…They also found that contrast-enhanced computed tomography revealed multiple feeding arteries within the masses and mild ring enhancement in several cases they examined. They believe these imaging features may be characteristic of intra-abdominal and retroperitoneal neuroectodermal tumors [13]. Mild ring enhancement was observed in 40% of cases.…”

Primitive Neuroectodermal Tumour Invading the Inferior Vena Cava

“…Furthermore, PNETs located peripherally typically express high amounts of the MIC2 antigen (CD99) [ 7 ] . However, recent updates have suggested heterogeneity in retroperitoneal PNET presentation, which is a combination of a pPNET with non-differentiated retroperitoneal sarcomas [ 8 ]. Hence, the ambiguous and vague presentation of the disease contributes to a complicated diagnosis.…”