Argyrophil nucleolar organizer regions (
AgNORs) were counted and immunostaining using
antibodies raised against
proliferating cell nuclear antigen (
PCNA) and Ki-67 was carried out on
eccrine acrospiroma and eccrine sweat gland
carcinoma, to determine the malignant potential and prognosis of these tumours.
Formalin-fixed and
paraffin-embedded tissue specimens surgically excised from 25 patients with eccrine sweat gland
carcinoma (20 cases of
eccrine porocarcinoma, four cases of ductal sweat gland
carcinoma and one case of malignant clear cell
hidradenoma) and 25 patients with
eccrine acrospiroma (16 cases of
eccrine poroma, four cases of
poroid hidradenoma and five cases of clear cell
hidradenoma) were used.
PCNA and Ki-67 labelling indices were categorized semiquantitatively into four grades. Significant differences were noted between eccrine sweat gland
carcinoma and
eccrine acrospiroma with these three methods (P < 0.01). When a cut-off of 5 was chosen, the AgNOR value distinguished eccrine sweat gland
carcinoma from
eccrine acrospiroma with high specificity and sensitivity. Moreover, we compared the results of these three methods between stages 1 or 2 (17 cases) and stage 3 (eight cases) eccrine sweat gland
carcinomas, and no significant differences were observed. From these findings, these three methods are useful in discriminating malignant from benign lesions of eccrine tumours, but have no value in estimating the aggressiveness of eccrine sweat gland
carcinomas.