KERATIN CYST-AN UNUSUAL CAUSE OF EYELID MASS E-POSTER

AUTHORS Dr. Abhishek Das (PG STUDENT) Dr. Surekha V. Bangal (PROFESSOR) Dr. Akshay Bhandari (ASSISTANT PROFESSOR)

INTRODUCTION Keratin cyst is a keratin-containing cyst lined by epidermis also known as Epidermal cyst. It is usually located over scalp, face, neck, chest, upper back and extremities. Also occur on breast, vulva, clitoris, penis, scrotum and perineum.  Prevalence rate is 1 cyst/2000 adults. It differs from dermoid cyst only in that dermal appendages are lacking. Slow growing, benign tumors that result from proliferation of surface epidermal cells within the dermis.

Histopathology The cyst is lined by true epidermis composed of several layers of stratified squamous epithelium including the granular layer. Within the cyst is keratinous material arranged in laminated layers. A foreign body type reaction with multinucleate giant cells may be present in the dermis surrounding the cyst in response to spillage of cyst contents.

CASE REPORT A 80 year old female presented with chief complains of painless swelling on the left upper eyelid since 8 years. Patient was aware of the swelling from the last 8 years but it has increased in size in last 1 year. No history of trauma, surgery or eyelid inflammation.

Clinical features A swelling at the left upper lid below the eyebrow measuring 1.5 × 2.0 × 1.5 cm.  Globular in shape with a smooth surface. It was soft in consistency, non-fluctuant, non-translucent, fixed to the overlying skin and freely mobile. Free from the underlying structures such as tarsus and orbital bones. The swelling was non-tender and local temperature was not raised. There were no pulsations or bruits over the swelling.  Mechanical ptosis was a prominent feature.

Treatment Surgical Excision of the cyst under local anesthesia done. A horizontal incision of 6-7 mm was taken. Cyst was dissected carefully from skin and subcutaneous tissue. Base of cyst was identified and excised with intact capsule. Skin sutured with 6-0 vicryl. Ptosis disappeared postoperatively. Histopathological examination revealed 1.5cm single, globular, soft to cystic mass with cheesy material inside. Section showed cyst wall lined by cornified with distinct granular layers and contains lamellated keratin. Underlying it, fibrocollagenous stroma along with few eccrine-apocrine glands are seen. Lumen of cyst shows keratin flakes.

Preoperative images Histopathology Keratin Postoperative images

Central punctum was absent.  Discussion In our case, the keratin cyst was located at the superior aspect of the eyelid which is not an usual presentation. It was huge enough to cause mechanical ptosis thereby reducing visual acuity of that eye. Central punctum was absent. There are several proposed mechanisms for epidermal cyst formation. It may arise from occlusion of the infundibular portion of the hair follicle. From implantation of epidermal cells into the dermis following penetration injury. From trapping of epidermal cells along embryonal fusion planes. HPV, especially types 57 and 60 have been identified in palmoplantar epidermoid cyst. Histopathologically the cyst is lined by true epidermis composed of layers of stratified squamous epithelium and contain keratinous material. The treatment is the excision of the cyst with intact capsule along with the cyst wall. Recurrence of the cyst is possible if the proper precautions are not taken while excising it surgically in toto.

Conclusion Keratin cyst is a rare cause of eyelid mass because eyelid is not the usual location of the cyst. Surgical excision of the cyst with intact capsule is treatment of choice as there is least chance of recurrence.

References Albert and Jakobiec, Principles and Practice of Ophthalmology, 2nd edition, vol-4, page-3803. R.G. Valia and Ameet R. Valia, IADVL Textbook of Dermatology, 3rd edition, vol-2, page-1506. Yanoff and Duker, Ophthalmology, 3rd edition, page-1424. Braun-Falco O. Dermatology. 2 nd ed. Berlin, Germany: Springer; 2000. p. 1423-40. Kronish JW, Sneed SR, Tse DT. Epidermal cysts of the eyelid. Arch Ophthalmol 1988;106:270.