Cytology in the diagnosis of retinoblastorna wasrecentl yexperienced in 4 cases. These 4 cases werefemale children and the diagnosis was clinicallysuspected. Specimen was obtained from each caseby aspiration of either aquous humor in the anteriorchamber, vitreous body or subretinal fluid. Cytological observation was made under Papanicolaoustain. Typical cells of retinoblastoma were detectedon smears. These cells were morphologically analyzed in terms of rossette formation, size and formof cells, cytoplasmic size, nuclear form and rim, chromatin distribution and shape of nucleoli.
Undifferentiated type showed no rossette formation, small sized cells and cytoplasms, irregular nuclearrims, increased amount of chromatin and increasednumber of nucleoli, whereas differentiated type tended to form rossette with fairly large sized cellsand cytoplasms. Of 4 cases, 1 case was cytologicallyclassified undifferentiated or well differentiated type, respectively, and the rest of 2 cases were classifiedmoderately differentiated type. These findings wereconfirmed by histological findings of the lesionswhich were surgically obtained after the cytologicalexamination.
