Department of General Surgery, District Hospital, Bandipore, Kashmir, India
*Corresponding author Email: email@example.com
Epidermoid cyst is a subcutaneous swelling. Giant epidermoid cysts are rare. The aim of this report was to study occurrence of giant epidermoid cysts.
All those who had giant epidermoid cysts from 2005 to 2012 were studied. A total of nine patients had giant epidermoid cysts. There were five females and four males. On the scalp, four had giant cysts, and two had a cyst on the root of the scrotum. The cyst size varied from 12.1 to 6.9 cm. A mutilocular cyst was present in one case while the rest had a unilocular type of cyst. None had a punctum visible. All had excision.
Giant epidermoid cysts are rare. Excision is the treatment of choice.
Epidermoid cyst is intradermal in origin and being adherent to the epidermis. This is the most common cutaneous cyst. Epidermoid cyst and sebaceous cyst are interchangeable terms. These usually present as a painless mobile swelling, sometimes an infected cyst can present as a painful swelling. A giant epidermoid cyst is defined as being more than 5 cm in any dimension. These can occur at any site on the body except the palm and soles. Clinical examination with preoperative fine-needle aspiration gives the diagnosis. Sometimes radiological investigations may be needed. A giant epidermoid cyst may get secondarily infected, may lead to pressure over the underlying bone and rarely undergoes malignant transformation. Epidermoid cysts have a well-developed granular cell layer and are lined by stratified squamous epithelium; rarely, pseudostratified ciliated columnar epithelium may be present on the cyst wall. The cyst wall can have dystrophic type calcification. Excision is the treatment of choice2. The aim was to study the occurrence of giant sebaceous cysts.
All those who had giant epidermoid cysts were studied from 2005 to 2012.
A total of nine patients had giant epidermoid cysts. All had clinical diagnosis with confirmation by fine-needle aspiration cytology. There were five females and four males. Giant sebaceous cysts on the scalp were present in four patients, two had cysts in the root of the scrotum and one had cysts in the right forearm and another had one on the leg. One case which had a giant cyst on the leg was perforated, and one who had a cyst on the chest wall was infected (Figure 1). All had preoperative fine-needle aspiration diagnosis of sebaceous cyst. The size ranged from 12.1 to 5.9 cm (Table 1). All epidermoid cysts on the scalp had occurrence in an area above the line drawn along hair line passing through the upper border of the ear lobule and joining these two lines at the occipital area (Figure 2). The control of infection was done before excision in infected cyst on the chest wall. All cysts were unilocular except one on the forearm which was multilocular. No evidence of malignancy was present. None had recurrence after a 2-year follow up.
Occurrence of giant sebaceous cyst on scalp.
Showing giant sebaceous cyst in female on scalp.
Characteristics of patient and the cyst
Giant epidermoid or sebaceous cyst is rarely seen in a surgical practice. These can occur at any age, rare before puberty, and the most common age of presentation is a young adult male. In this series all the patients were above 50 years, only one case was a 12-year-old female. The most common site of occurrence is the face, trunk, neck, scalp, scrotum, ear lobe and breast but, location at an unusual site raises concern. Rarely, they may occur in a setting of hereditary syndromes like Gardener’s syndrome, basal cell nevus syndrome and panchyonchia congenital. These are common in females usually on the scalp, more in people working in outdoor conditions with sunlight exposure and unhygienic concerned areas. On the scalp, it occurs in an area located in a line drawn along the hair line passing through the upper border of the ear lobule and joining these two lines at the occipital area. This a retention type of cyst and usually unilocular and contains keratin. Normal size varies from a few millimetres to a few centimetres but when the size exceeds 5 cm, it is referred to as a giant sebaceous cyst. The detection of small cysts and evolving into giant cysts takes years and it grows usually at a rate of not more than 0.5 cm per year. In the initial years, growth is more rapid than after attaining large size. Neglection on part of the patient in seeking surgical advice when the cyst is small leads to formation of a giant epidermoid cyst. Sebaceous cyst is a subcutaneous swelling with a punctum which is a hallmark in diagnosis. It is difficult to detect a punctum in large sebaceous cyst. Punctum in a giant sebaceous cyst is difficult to detect as swelling enlarges, because more and more hair follicles overlying it make it difficult to detect and makes them wider follicles. Occasionally small sebaceous cyst exist together with a giant one; four small epidermoid cysts (size <3 cm) were present in a patient with a cyst on the forearm, three small epidermoid cysts (size <2 cm) on the scalp with a giant cyst on the scalp were seen in a 52-year-old female and a single epidermoid cyst (size <2 cm) was present on the groin of a 52-year-old male. A pressure on the overlying skin leads to thinness, and rarely necrosis, leading to perforation through which the contents escape. Anatomical location and size of the cyst with native intrinsic skin thickness determines propensity to perforate. Thin skin on the leg is more prone to pressure necrosis by growing cysts than in the scalp due to intrinsic thick nature of skin on the scalp. Giant epidermoid cysts have a propensity to develop malignancy. Giant epidermoid cysts in the groin may mimic as hernia, lymphadenopathy, hydrocele, undescended testes and abscess.
These originate from epidermal cells, an outer skin layer, and grow gradually. Incorrect implantation of remnant ectodermal tissue during embryogenesis, traumatic or surgical implantation of epithelial elements, blocked sebaceous gland and damage to hair follicle predispose to epidermoid cyst formation. A sebbborheic dermatitis was present in all our patients who, except one, had a cyst on the leg and, histopathological evidence of chronic dermatitis has been documented in the excised specimen. Various types of malignancy that can arise from a giant sebaceous cyst are squamous cell carcinoma, basal cell carcinoma, mycosis fungoides and melanoma[10,11]. No patient had any evidence of malignancy. X-ray was done to rule out any pressure symptoms on the underlying bone. Fine-needle aspiration cytology confirms diagnosis in all. Excision is the treatment of choice.
Giant epidermoid cysts are rare. They are found more on the scalp, and excision is the treatment of choice.
All authors contributed to the conception, design, and preparation of the manuscript, as well as read and approved the final manuscript.
All authors abide by the Association for Medical Ethics (AME) ethical rules of disclosure.
Characteristics of patient and the cyst
|52||F||Scalp||10.6 × 8.2||Excision|
|65||F||Scalp||9.2 × 3.8||Excision|
|55||F||Scalp||8.8 × 2.9||Excision|
|66||M||Groin||12.1 × 4.3||Excision|
|70||M||Scalp||8.1 × 5.6||Excision|
|13||F||Forearm||9.5 × 2.2||Excision|
|57||M||Chest wall||7.3 × 2.1||Excision|
|60||F||Leg||6.9 × 3.3||Excision|
|75||M||Groin||8.7 × 4.3||Excision|