Solitary pedunculated growth in a child

Abstract

A young girl presented to us with a solitary asymptomatic pedunculated mass over her right arm. Histology of the excised mass revealed features suggestive of pedunculated lipofibroma. The paucity of documentation of pedunculated lipofibroma in this age group incited the present report.

INTRODUCTION

Pedunculated lipofibroma is a hamartoma developing from the connective tissue, characterized by the presence of ectopic, mature adipose tissue in the dermis,[¹] which is better known as solitary variant of nevus lipomatosus cutaneous superficialis (NLCS). In contrast to the multiple variety of NLCS, the solitary lesion is known to appear in adults. However, there are rare reports of presentation of pedunculated lipofibroma in children. Hereby, we present a case of solitary pedunculated lipofibroma in a child.

CASE REPORT

A 13-year-old healthy girl presented to us with an asymptomatic, gradually progressive swelling hanging down from her right arm for the last 4 years. Initially, the swelling was small in size with an insidious onset, which gradually enlarged to attain the present dimension. Cutaneous examination revealed a solitary, nontender, well-defined, pear shaped pedunculated mass, measuring approximately 8.5 cm × 6 cm, hanging down from the central part of her right arm by a prominent stalk [Figure 1]. The lesion was soft to firm in consistency; the overlying skin being wrinkled at places [Figure 2]. Systemic examination and routine biochemical investigations were unremarkable. The pedunculated growth was subjected to excisional biopsy; histopathological examination revealed strands of fibrocollagenous tissue in the upper part of dermis, while the lower part demonstrated abundantly scattered adipose tissue with interspersed strands of fibrocollagenous tissue [Figures 3 and 4]. The epidermis and basal layer were normal; no giant cells, foamy histiocytes, atypical cells or evidence of malignancy was noted. Based on the clinicopathological correlation, a diagnosis of pedunculated lipofibroma/solitary NLCS was done.

Figure 1: Solitary, pedunculated growth from the right arm with a prominent stalk

Figure 2: Surface of the growth showing a wrinkled appearance

Figure 3: Photomicrograph showing abundant fibrocollagenous and mature adipose tissue in the dermis (H and E, ×10)

Figure 4: Photomicrograph showing abundant mature adipocytes in the reticular dermis with interspersed fibrocollagenous tissue (H and E, ×40)

DISCUSSION

Pedunculated lipofibroma is a rare, benign hamartomatous lesion arising from the connective tissue, characterized by the presence of ectopic, mature adipose tissue in the dermis;[¹] also referred to as the solitary variant of NLCS. NLCS is a rare, benign tumor arising from the connective tissue; which was first described by Hoffmann and Zurhelle in 1921.[²] There are two broad types of NLCS according to the presentation: A multiple or classical form and a solitary form. Both the varieties are characterized by the presence of ectopic, mature adipose tissue in the dermis.[¹] Owing to its distinct clinicopathological picture, Mehregan et al.[³] proposed the term "pedunculated lipofibroma" for the solitary form of nevus lipomatosus.

The multiple variety of NLCS, is usually congenital in origin or appears within the first three decades; mostly situated over the buttocks, sacrococcygeal region, and upper posterior thigh.[⁴] They present as grouped soft, smooth papules or nodules, which may coalesce to form a domed plaque; having a verrucous or cerebriform surface.

The solitary variant usually presents as a single papule or nodule, which may be pedunculated (pedunculated lipofibroma) or sessile. In contrast to the multiple variety, this entity usually appears in the adult life;[⁴] however neonatal[¹] and infantile[⁵] cases have been reported. The usual sites of predilection are axilla, knee, ear, arm, and scalp apart from the lower trunk;[⁴] rarer sites been reported include palms,[⁶] eyelid,[⁷] and elbow[⁵] and perianal area.[⁸] Besides, a huge nevus lipomatosus cutaneous superficialis has also been reported.[⁹]

The pathogenesis of pedunculated lipofibroma is yet to be elucidated, however, degenerative changes of collagen and elastic tissue, and altered differentiation of dermal vessel walls may play a role.[²]

The characteristic histological finding in both varieties of NLCS is the ectopic collection of mature lipocytes within the dermis,[⁴] although the amount is variable. Occasionally, there is an excessive proliferation of fibrocollagenous tissue (as in our case), which may be demonstrated by staining with Alcian blue.[⁶] The blood vessels may be increased in number, often surrounded by fat cells. The main differentials, which can be considered in our case, include benign papillomas such as acrochordon, seborrheic keratosis, intradermal melanocytic nevi, neurofibromas, verrucae and fibroepithelioma of Pinkus. Our diagnosis was confirmed by its characteristic histopathological picture.

Treatment is usually not needed except for cosmetic purposes. If needed, surgical excision forms the mainstay of treatment, which was also performed in our case. Pedunculated lipofibroma is an uncommon entity in the pediatric population, which prompted us to report the case.

Financial Support and Sponsorship

Nil.

Conflicts of Interest

There are no conflicts of interest.