Eccrine porocarcinoma and Bowen's disease arising in a seborrhoeic keratosis

Abstract

An association between seborrhoeic keratosis (SK) and malignant tumours is considered to be rare. We observed a case of eccrine porocarcinoma and Bowen's disease (BD) occurring synchronously, forming one lesion in a SK on the abdomen. It is controversial whether malignant neoplasms arising in SK occur only by chance or if pre-existing SK plays a role in pathogenesis. This case suggests an implication of pre-existing SK in the subsequent development of both BD and eccrine porocarcinoma.

Porocarcinoma; presentation and management, a meta-analysis of 453 cases

“…These includes; ductal differentiation, nests of basaloid cells, squamoid tumor cells, infiltrative spinal cells, cells of acanthotic epidermis, Borst Judasson appearance, ulcerated epithelial tumor, bowenoid porocarcinoma, nests of small atypical cells, clear-cell, high infilterative pattern and hyperchromatic nuclear [7], [13], [26], [62], [72], [103], [102]. Surgery was the main mode of therapy with adjuvant chemoradiotherapy if metastasis and/or recurrence occurred [50], [82], [83], [84], [85], [86], [87], [88], [89], [90], [91], [92], [93], [94], [95], [96], [97], [98], [99], [100], [101], [102], [103], [104]. Metastasis was found in 110 (31%) cases [3], [10], [63], [65], [68], [73], [76], [86].…”

Zosteriform Metastases of Eccrine Porocarcinoma Mimicking Eruptive Seborrhoeic Keratoses

“…Although the association between SK and malignant skin tumours within one lesion has been sporadically reported since 1932 (12), this is generally considered a rare combination. Most tumours reported to occur within SK are known to be BCCs (13).…”

“…One occurred synchronously with Bowen's disease, forming a single lesion on a preexisting SK of the abdomen (12). In the 2 other reported cases eccrine porocarcinoma arose within a preexisting SK on the abdomen (14).…”

Squamous cell carcinomas in situ arising in seborrheic keratoses: an association with concomitant immunosuppression?

“…Christeler and Delacretaz first described a case of SCCIS arising in an SK. Subsequently, other cases have been reported . Given the large numbers of SKs evaluated histologically, it is surprising their malignant degeneration has not been reported more frequently, although this phenomenon may not be a rare occurrence.…”