title: Mucinous adenocarcinoma associated with chronic suppurative hidradenitis: Report of a case and review of the literature.
abstract: BACKGROUND
  Chronic suppurative hidradenitis (CSH) is a benign condition that can affect the perineal region and often leads to the formation of abscesses and fistulas. It is rare for CSH to undergo malignant degeneration into mucinous adenocarcinoma.
  
  
  METHODS
  We report a case of a 55-year-old male patient with perineal CSH who suffered worsening long-term pain despite multiple surgical procedures to alleviate his symptoms. Pelvic magnetic resonance imaging (MRI) showed multiloculated cystic lesion on the left side wall of the distal rectum with gluteal extension. Pathological examination revealed mucinous adenocarcinoma. The patient underwent an abdominoperineal resection (APR) of the rectum with cutaneous muscle flap reconstruction. Although histopathological sections showed clear margins, the tumor recurred 6 months following surgery.
  
  
  CONCLUSIONS
  Perineal mucinous adenocarcinoma arising in a patient with CSH is an extremely rare condition. This diagnosis is often difficult, due to the paucity of signs of malignant degeneration as well as the rarity of the disease itself. Surgical resection of the lesions is a well-established approach. In this case, diagnosing the tumor at such a late stage likely compromised his outcome.
  
  
  CONCLUSIONS
  Malignant degeneration to mucinous adenocarcinoma must be suspected in patients with a history of long-term CSH. In such cases, local biopsies and a radiological examination, such as MRI can help in the diagnosis.
authors.affiliation: Coloproctology Unit, Department of Surgery, University of Campinas, UNICAMP, Campinas, Sao Paulo, Brazil.
authors.forename: Natalia
authors.initials: N
authors.lastname: Mukai
authors.affiliation: Coloproctology Unit, Department of Surgery, University of Campinas, UNICAMP, Campinas, Sao Paulo, Brazil.
authors.forename: Lílian Vital
authors.initials: LV
authors.lastname: Pinheiro
authors.affiliation: Coloproctology Unit, Department of Surgery, University of Campinas, UNICAMP, Campinas, Sao Paulo, Brazil.
authors.forename: Maria de Lourdes Setsuko
authors.initials: Mde L
authors.lastname: Ayrizono
authors.affiliation: Plastic Surgery Unit, Department of Surgery, University of Campinas, UNICAMP, Campinas, Sao Paulo, Brazil.
authors.forename: Guilherme Cardinali
authors.initials: GC
authors.lastname: Barreiro
authors.affiliation: Plastic Surgery Unit, Department of Surgery, University of Campinas, UNICAMP, Campinas, Sao Paulo, Brazil.
authors.forename: Paulo
authors.initials: P
authors.lastname: Kharmandayan
authors.affiliation: Plastic Surgery Unit, Department of Surgery, University of Campinas, UNICAMP, Campinas, Sao Paulo, Brazil.
authors.forename: Mariana Hanayo
authors.initials: MH
authors.lastname: Akinaga
authors.affiliation: Plastic Surgery Unit, Department of Surgery, University of Campinas, UNICAMP, Campinas, Sao Paulo, Brazil.
authors.forename: Adriano Mesquita
authors.initials: AM
authors.lastname: Bento
authors.affiliation: Coloproctology Unit, Department of Surgery, University of Campinas, UNICAMP, Campinas, Sao Paulo, Brazil.
authors.forename: Carlos Augusto Real
authors.initials: CA
authors.lastname: Martinez
authors.affiliation: Department of Pathology, Gastrocenter, University of Campinas, UNICAMP, Campinas, Sao Paulo, Brazil.
authors.forename: Rita Barbosa
authors.initials: RB
authors.lastname: de Carvalho
authors.affiliation: University of Chicago Medical Center, Chicago, IL, United States.
authors.forename: Marc
authors.initials: M
authors.lastname: Ward
authors.affiliation: Coloproctology Unit, Department of Surgery, University of Campinas, UNICAMP, Campinas, Sao Paulo, Brazil.
authors.forename: Cláudio Saddy Rodrigues
authors.initials: CS
authors.lastname: Coy
authors.affiliation: Coloproctology Unit, Department of Surgery, University of Campinas, UNICAMP, Campinas, Sao Paulo, Brazil. Electronic address: rafranco.unicamp@gmail.com.
authors.forename: Raquel Franco
authors.initials: RF
authors.lastname: Leal
keywords: Case report; Chronic suppurative hidradenitis; Colorectal surgery; Mucinous adenocarcinoma