NM-23 gene expression and proliferative activity as prognostic indicators in rhabomyosarcoma

ABSTRACT

To determine nm-23 expression and percentage of Ki-67 labeling index and to correlate these findings with other, rognostic parameters, in rhabdomyosarcoma cases [RMS]. Specimens of 25 cases of rhabdomyosarcoma were studiedfornm-23 antigen immunohistochemically. For evaluation of proliferative activity of tumors, mitotic figures and Ki-67 labeling index were investigated. Ailfindings were analyzed statistically. Fifteen patients were embiyonal rhabdomyosarcoma and ten cases were alveolar rhabdomyosarcoma. Four JMIzents [16%] were stage 1, two [8%] were stage 2, nine [36%] were stage 3 and ten [40%] were stage 4. The percentage of nm-23 positivity was 52%. A significant association was found between nm23 expression and metastasis [p=0.010], where 80% of cases with metastasis at the time of diagnosis showed negative nm-23 expression. On linear regression analysis, Nm-23 expression showed sign[ficant levelfor prediction of metastasis [p=0.042], while initotic figures and Ki-67 labelling index did not reach statistically significant level [p=0.6l9, p=0.062]. These findings suggested that nm-23 expression might be used as a reliable indicator for metastatic potentiality of rhabdomyosarcoma. Further larger prospective studies are neededfor ident ifi cation of other prognostic markers specific for RMS to help us better understand the mechanisms involved in the patho genesis and facilitate the development of novel effective therapies