title: Timeline of recurrence after primary and secondary pilonidal sinus surgery.
abstract: OBJECTIVE
  This study was designed to evaluate the timeline of recurrence of pilonidal sinus disease after primary vs. multiple surgery. Data of medical military service in Germany were reviewed.
  
  
  METHODS
  Telephone interview of 205 patients after pilonidal sinus disease surgery after median interval of 14.8 (standard deviation +/-3.9) years was conducted. A total of 345 patient charts with pilonidal sinus disease recurrence and fully documented previous surgery history were analyzed.
  
  
  RESULTS
  Pilonidal sinus disease recurred in 41 of 205 patients (20 percent; actuarial survival 22 percent) after first surgery. Median recurrence-free-interval was 1.8 (range, 0.1-16.5) years. Twenty-nine of 41 of all recurrences (71 percent) were observed within four years after primary surgery. Fifteen of 50 patients (30 percent) treated by primary closure had recurrent disease after a median recurrence-free interval of 2.7 (range, 0.2-13.5) years compared with 24 of 144 patients (17 percent), who experienced recurrence after rhomboid excision and open wound treatment after a median of 1.8 (range 0.1-16.5) years (P = 0.081, long-rank-test). Analysis of 345 recurrent disease charts revealed that recurrence time decreased for multiple recurrences compared with first recurrence (R1 vs. R2: P = 0.07; R2 vs. R3: P = 0.03, Mann-Whitney U test).
  
  
  CONCLUSIONS
  Long-term recurrence rate was 22 percent and thus higher than previously reported. This may be attributed to the long follow-up interval. Recurrences up to 20 years after surgery were seen. Our data provide evidence that follow-up after first to the third pilonidal sinus surgery should complete or exceed five years, because the majority of recurrences occur during this postoperative interval. Nevertheless, even a five-year follow-up will still miss 25 percent of recurrences.
authors.affiliation: Department of Surgery, Bundeswehrkrankenhaus Berlin, Berlin, Germany. ddoll@gmx.de
authors.forename: Dietrich
authors.initials: D
authors.lastname: Doll
authors.forename: Colin M
authors.initials: CM
authors.lastname: Krueger
authors.forename: Stefan
authors.initials: S
authors.lastname: Schrank
authors.forename: Heidi
authors.initials: H
authors.lastname: Dettmann
authors.forename: Sven
authors.initials: S
authors.lastname: Petersen
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Duesel
mesh_terms: D006801:Humans; D010864:Pilonidal Sinus / Q000601:surgery*; D012008:Recurrence; D012086:Reoperation; D013997:Time Factors