Benign eccrine poroma in the palm of the hand.

Benign eccrine poroma arises from the intraepidermal portion of the eccrine gland duct and was first described by Pinkus et al1 in 1956. They are usually common in middle aged or elderly patients and present clinically as solitary, painless soft masses without associated symptoms. When these lesions present with pain, bleeding or itching, the possibility of malignant transformation should be considered. In this case report we present a rare occurrence of eccrine poroma in the palm of the hand.

Case

A 90-year-old, diabetic male presented with a 2-year history of a growing mass in the palm of the left hand. The lesion had gradually increased in size. One year from the onset of the swelling, a foreign body (date palm thorn) was removed from the same site, but there was no regression in the size of the mass or history of discharge. There were no associated neurological or vascular symptoms in the hand. Physical examination revealed a 4 × 3 cm ulcerated, tender, firm and mobile mass in the subcutaneous plane of the hand, which was attached to the skin near the center (Figure 1). Motor and sensory functions were normal and there was no evidence of lymphadenopathy. An x-ray of the hand and hematological tests were normal. Clinically, a foreign-body granuloma was suspected and excision was planned. The whole mass was excised, including an ellipse of skin and subcutaneous fat. Histological examination revealed a benign adnexal neoplasm with a characteristic population of cuticular and eccrine glandular cells with formation of ductal structures and intraluminal secretions (Figure 2). The patient remained well with no evidence of recurrences after one year of careful follow up.

Figure 1

Benign eccrine poroma in the palm of the left hand.

Figure 2

Benign eccrine poroma tumor, consisting of sheets of uniform small cuboidal cells with intervening narrow ductal lumina lined by eosinophilic cuticles (H/E stain x 40).

Discussion

Eccrine poroma is fairly common solitary tumor found on the sole or the side of the foot, in about two-thirds of cases, on the hands and fingers, and less frequently in other areas such as the neck and nose. In its typical form, eccrine poroma arises from within the lower portion of the epidermis and extends to the dermis in broad anatomizing bands of tumor cells. Differential diagnoses include pyogenic granuloma, verruca vulgaris, seborrheic keratosis, fibroma, melanoma, adnexal cysts, vascular tumors, basal cell carcinoma and squamous cell carcinoma. The management of eccrine poroma should be complete excision, including a small amount of grossly normal skin and subcutaneous tissue. Recurrence after incomplete excision has occurred in different regions of the body.2–4 For this reason, patients should be followed up with close observation for possible recurrence and the development of new lesions in other areas of the body. Histologically proven transformation of cases from benign to malignant tumors in other parts of the body have been reported in the literature.5 Eccrine poroma occurs very rarely in the palm. We reviewed the medical literature for 1956 to 2000 and found only 8 cases of eccrine poroma of the palm.6,7 Due to rarity of this lesion in the palm of the hand, plastic and hand surgeons should be aware of this unusual and unexpected benign tumor at this site and the probability of transformation into a malignant neoplasm. Adequate excision and a period of close follow up is the management of choice.