Conservative vs Surgical Interventions for Umbilical Pilonidal Sinus: A Multicenter, Double-Blind, Prospective, Randomized Clinical Trial Mehmet Kaplan, MD, Onder Ozcan, MD, Fatma Cigdem Kaplan, MD, Huseyin Cahit Yalcin, MD, Bulent Salman, MD, FACS BACKGROUND: Umbilical pilonidal sinus (UPS) is one of the most neglected disorders, and there is still no clear consensus regarding optimal treatment of the disease. We therefore present our data from a prospective, randomized, controlled clinical trial comparing conservative vs surgical treatment of UPS. STUDY DESIGN: The study was conducted in Turkey between January 2012 and November 2015. All eligible patients with the diagnosis of UPS (n ¼ 84) were randomized for either conservative treat- ment (CT, n ¼ 42) or surgical treatment (ST, n ¼ 42). All patients were followed up for at least 2 years; then, the results of both groups were compared. The primary outcomes were initial healing, recurrence, and the cure rate of the disease after each treatment modality. RESULTS: Mean ( SD) age of the patients was 20.83  5.73 years old, and the majority were men (94%). Nearly 60% of the patients had a deep navel, and 55% had intense hair status. The main symptoms were drainage and wetness, pain, itching, and malodor. Overall, in 10 (27.8%) patients, relapse of the disease was observed in the CT group; it was observed in only 1 patient in the ST group (p ¼ 0.002). Initial healing time was significantly shorter in the ST group (p ¼ 0.001). Of the 81 patients who completed the 2-year follow-up, a cure could be obtained in only 28 of 41 patients in the CT group; it was achieved in all 40 patients in the ST group (68.3% vs 100%, respectively; p ¼ 0.0001). CONCLUSIONS: This study provided evidence that surgical treatment is superior to conservative surgery regarding the primary and secondary outcomes of UPS at least 2 years after surgery. (J Am Coll Surg 2016;-:1e12. Ó 2016 by the American College of Surgeons. Published by Elsevier Inc. All rights reserved.) Pilonidal sinus disease is a common health problem. It is seen most frequently in the sacrococcygeal region. However, it can also be observed in the umbilicus. Because of its rarity, umbilical pilonidal sinus (UPS) is still poorly understood in terms of diagnosis, etiology, and the best treatment options. The term umbilical pilo- nidal sinus was first described by Williams and Patey in 1956. 1 Since that time, there have been no more than 30 to 40 reports in the literature. The cause of UPS is believed to be hair penetrating the skin, leading to a foreign-body reaction and the develop- ment of a sinus lined with granulation tissue. Most patients complain of pain, discharge, or bleeding from the umbilicus when symptoms develop. The UPS can be diagnosed with a careful examination, in which hairs can be seen deep in the umbilicus and usually protruding from a small sinus. 2 The incidence and the prevalence of the disease are believed to be 0.6% and 0.1%, respec- tively, and it is more common in male patients. 3 There have been some conflicting data and claims related to the disease in the literature. Some authors Disclosure Information: Nothing to disclose. This study is registered at ClinicalTrials.gov with number NCT01662765, and the name of the trial is registered as “Conservative vs surgical treatment of umbilical pilonidal disease.” Full details of the trial protocol can be accessed at: https://clinicaltrials.gov/ct2/show/NCT01662765. Received December 28, 2015; Revised January 24, 2016; Accepted January 25, 2016. From the Departments of General Surgery, Bahcesehir University (BAU) School of Medicine, Istanbul (M Kaplan); Sitki Kocman University School of Medicine, Mugla (Ozcan); Dr Ersin Arslan Government Hospital, Gaziantep (Yalcin); and Gazi University School of Medicine, Ankara (Salman), Turkey; and 25-Aralik Family Physician Health Center (FC Kaplan), Gaziantep, Turkey. Correspondence address: Mehmet Kaplan, MD, Medical Park Gaziantep Hastanesi, Genel Cerrahi Departmani, Mucahitler mah. 27090, Sehitkamil, Gaziantep, Turkey. email: mehmet.kaplan@med.bahcesehir.edu.tr 1 ª 2016 by the American College of Surgeons. Published by Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.jamcollsurg.2016.01.056 ISSN 1072-7515/16