International Surgery Journal | March 2023 | Vol 10 | Issue 3 Page 524 International Surgery Journal Dave DM et al. Int Surg J. 2023 Mar;10(3):524-527 http://www.ijsurgery.com pISSN 2349-3305 | eISSN 2349-2902 Case Report A diagnostic dilemma: unusual case report of a dermoid cyst embellished with a tattoo in the midline of neck Dhruva M. Dave*, Jaydip R. Kavthiya, Darshan J. Gajera INTRODUCTION A dermoid cyst is a benign cutaneous developmental anomaly that arises from the entrapment of ectodermal elements along the lines of embryonic closure. 1,2 These benign tumours are lined by stratified squamous epithelium with mature skin appendages found on their wall and their lumens filled with keratin and hair. 3 Dermoid cysts are considered to be congenital, but not all of them are diagnosed at birth. 3-5 Only about 40% of dermoid cysts are diagnosed at birth, while about 60% of the dermoid cysts are diagnosed by five years of age. 3 They are true hamartomas focal malformations that can resemble neoplasms grossly and even microscopically. Meyer updated the concept of dermoid cyst to describe the following histological variants: true dermoid cyst, the epidermoid cyst, and the teratoid cyst. True dermoid cysts are cavities lined with epithelium showing keratinization and with identifiable skin on the cyst wall. Epidermoid cysts are lined with simple squamous epithelium with a fibrous wall and no attached structures. The lining of a teratoid cyst varies from simple squamous to a ciliate respiratory epithelium containing derivatives of ectoderm, mesoderm, and/or endoderm. All three histological types contain a thick, greasy looking material. 6 A swelling in the midline of the neck is a site which has an array of differential diagnoses. Of which, thyroid gland swellings, tumors, cysts, malignant lesions, lymph node swellings, lymphomas and lipomas are few of the most common ones. They usually present with increasing size which presses on the vital organs and structures beneath, leading to difficulty in breathing and swallowing. In dermoid cysts, the ideal surgical intervention is the careful complete surgical excision of the cystic lesion to avoid complications and recurrence. ABSTRACT Dermoid cysts are benign congenital tumours of ectoderm origin usually arising from the midline where the fusion of embryonic structures of both sides occurs. They are true hamartomas focal malformations that can resemble neoplasms grossly and even microscopically. We hereby presented a case of a 25 year old male presented with complaints of a midline neck swelling for 5 years which was found just beneath a symbol tattooed in the skin overlying the swelling. The USG, fine needle aspiration cytology and multislice CT scan reports strongly suggested findings of a dermoid cyst. However, there was a diagnostic challenge faced when chest CT suggested old granulomatous changes around the swelling region. After thorough history taking, physical examination and radiological investigations, the swelling was successfully excised with a complete margin which was sent for histo- pathological examination, results of which correlated with the initial diagnosis of it being a dermoid cyst with foreign- body reactions. Keywords: Neck midline swellings, Dermoid cyst, Foreign-body reaction GMERS Medical College and Hospital, Gotri, Vadodara, Gujarat, India Received: 25 January 2023 Accepted: 15 February 2023 *Correspondence: Dhruva M. Dave, E-mail: dhruva.dave09@gmail.com Copyright: © the author(s), publisher and licensee Medip Academy. This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. DOI: https://dx.doi.org/10.18203/2349-2902.isj20230514