title: Metastatic mesenteric dedifferentiated leiomyosarcoma: a case report and a review of literature.
abstract: BACKGROUND
  Abdominal leiomyosarcoma arising from the mesentery is a rare malignancy. It is an aggressive entity with an overall 5 year survival rate between 20 and 30 %. Surgical resection is the cornerstone of primary treatment and may be curative for localized disease. However, patients often develop intra-abdominal relapse and/or metastatic disease. If surgical resection is not feasible, palliative chemotherapy is the treatment of choice. However, there are no clear guidelines regarding chemotherapy; neither in the adjuvant nor advanced setting.
  
  
  METHODS
  We present a 40 year-old woman, with a mesenteric leiomyosarcoma, who underwent radical tumor resection and did not receive adjuvant oncological therapy. Three months postoperatively, she developed metastatic disease to the lungs and liver. After multidisciplinary assessment she received an unconventional histological-subtype-tailored chemotherapy comprising 3-4 regimens. Initially, there was a decrease both in number and size of metastases. Ultimately, an almost complete radiological response was seen. Subsequent surgical resection and radiofrequency ablation of residual metastatic foci in the liver and lung brought her into complete clinical remission. She is presently tumor free, 36 months following diagnosis of metastatic disease.
  
  
  CONCLUSIONS
  To our knowledge, this is the first report of a patient with metastatic mesenteric leiomyosarcoma who is in complete clinical and radiological long-term remission following very aggressive multimodal treatment; including intense poly-drug chemotherapy and without any demonstrable long-term side effects. Given the rarity of mesenteric leiomyosarcoma and lack of guidelines regarding oncological therapy, we suggest that multimodal therapy including aggressive chemotherapy, guided by a multidisciplinary team, is essential to achieve an optimal outcome.
authors.affiliation: Department of Oncology, Oslo University Hospital, The Norwegian Radium Hospital, Ullernchausseen 70, 0379 Oslo, Norway ; Department of Surgery, Nordland Hospital, 8092 Bodoe, Norway.
authors.forename: Mercy
authors.initials: M
authors.lastname: Varghese
authors.affiliation: Department of Oncology, Oslo University Hospital, The Norwegian Radium Hospital, Ullernchausseen 70, 0379 Oslo, Norway ; Institute for Clinical Medicine, Faculty of Medicine, University of Oslo, Box 1171, Blindern, 0450 Oslo, Norway.
authors.forename: Oyvind
authors.initials: O
authors.lastname: Bruland
authors.affiliation: Department of Radiology, Oslo University Hospital, The Norwegian Radium Hospital, Ullernchausseen 70, 0379 Oslo, Norway.
authors.forename: Anne Marit
authors.initials: AM
authors.lastname: Wiedswang
authors.affiliation: Department of Pathology, Oslo University Hospital, The Norwegian Radium Hospital, Ullernchausseen 70, 0379 Oslo, Norway.
authors.forename: Ingvild
authors.initials: I
authors.lastname: Lobmaier
authors.affiliation: Gastrointestinal and pediatric surgery, Section for Hepatopancreatobiliary Surgery, Oslo University Hospital Rikshospitalet, Sognsvannsveien 20, 0424 Oslo, Norway.
authors.forename: Bård
authors.initials: B
authors.lastname: Røsok
authors.affiliation: Department of Sarcoma Medical Oncology, The University of Texas M. D. Anderson Cancer Center, Texas, Houston 77030 USA.
authors.forename: Robert S
authors.initials: RS
authors.lastname: Benjamin
authors.affiliation: Department of Oncology, Oslo University Hospital, The Norwegian Radium Hospital, Ullernchausseen 70, 0379 Oslo, Norway.
authors.forename: Kirsten Sundby
authors.initials: KS
authors.lastname: Hall
keywords: Abdominal; Chemotherapy; Histological-subtype; Leiomyosarcoma; Mesenteric; Metastases; Multimodal