RAPID AND UNBIASED ESTIMATION OF THE VOLUME OF CUTANEOUS MALIGNANT-MELANOMA USING CAVALIERIS PRINCIPLE

The Cavalieri volume estimator has been employed to determine the macr oscopic tumor volume of 34 cutaneous malignant melanomas. With this ra pid and unbiased method using histological specimens from slabs of kno wn thickness, tumor volumes between 3.9 mm(3) and 841.5 mm(3) were fou nd. The coefficient of error (CE) for tumor volumes ranged between 0.0 28 and 0.141, with a combined group CE of 0.043. Then was a remarkably good correlation between tumor volume and maximal vertical tumor thic kness estimated according to Breslow, with a correlation coefficient o f r = 0.86 for all tumors, and of r = 0.82, if the one extremely big t umor is omitted. Both inter- and intraobserver variability was very lo w, with only similar to 1-2% difference. Thus, the method described al lows for the reproducible, rapid, and unbiased estimation of tumor vol ume independent of the shape of the tumor.