Extracranial primitive, neuroectodermal tumors in Pakistan

ABSTRACT

Our objective was to diagnosed these tumors by CT [Computerized tomography] and MRI [Magnetic Resonance Imaging]. The study was conducted between August-2002 to December-2003 in radiology department of Shaukat Khanum Memorial Cancer Hospital and Research Centre [SKMCH and RC], which is a tertiary care center for cancer patients. The patients included in this study were diagnosed cases of non CNS PNET, who had been referred for staging work up and treatment. The biopsy was done either in the radiology department and later processed by pathology department of this hospital or the pathologists reviewed slides of biopsy done in other hospitals. The diagnosis was based on characteristic histology of the tumor and on presence of a positive MIC2 antibody. Case-series. In concordance to previous studies, PNET was found more in males than females [55% vs. 45% respectively]. Maximum no of patients belonged to 10-20 years of age group [47.6%]. As for the radiological features like presence of calcification, adenopathy and pleural effusions, observations made in this study were quite different from previous studies. Calcification was seen in 21.4% in comparison to previous reported incidence of 10%. Lymphadenopathy was seen only in 9.5% of our study patient in comparison to 83.3% of previous study done. Again pleural effusion in contrast to a reported incidence of 45-85% respectively was seen in 7.1% of our study patients. The tumor either due to local infiltration or due to metastases was mostly non-resectable at presentation [90%]. Resection was possible in three long bone PNET's, where amputation at the uninvolved proximal joint was done. This study analysis showed no difference with results obtained by others. However, the observed frequency of radiological features was very different to that reported in others studies. Again it was observed that the CT and MR findings of PNET are nonspecific and these imaging modalities help in delineating the local extent of the disease and metastatic spread. More multicenter studied are needed to support this study