title: Regional hyperthermia of the abdomen, a pilot study towards the treatment of peritoneal carcinomatosis.
abstract: BACKGROUND
  Peritoneal carcinomatosis occurs in different cancer subtypes and is associated with a dismal prognosis. Some doubts remain whether the whole abdomen can be treated by regional hyperthermia, therefore we analyzed feasibility conducting a pilot study.
  
  
  METHODS
  A simulation of the abdominopelvic heat distribution in 11 patients with peritoneal carcinomatosis was done using the HyperPlan software and the SIGMA-60 and SIGMA-Eye applicators. Tissue-specific region-related electrical and thermal parameters were used to solve the Maxwell's equations and the bioheat-transfer equation. Three-dimensional specific absorption rate (SAR) distributions and, additionally, estimated region-related perfusion rates were used to solve the bioheat-transfer equation. The predicted SAR and temperature distributions were compared with minimally invasive measurements in pelvic reference points.
  
  
  RESULTS
  In 11 patients (7 of them treated in the SIGMA-60 and 4 in the SIGMA-Eye applicator) the measured treatment variables (SAR, temperatures in the pelvic reference points) indicated that the heated volumes were higher for the SIGMA-Eye applicator. The mean computed abdominal SARs were less for the SIGMA-Eye (33 versus 44 W/kg). Nevertheless, the temperature distributions in the abdomen (peritoneal cavity) were more homogeneous in the SIGMA-Eye applicator as compared to the SIGMA-60 as indicated by higher values of T90 (mean 40.2 versus 38.2 °C) and T50 (mean 41.1 versus 40.2 °C), while the maximum temperatures were similar (in the range 41 to 43 °C). Even though the mean abdominal SAR was lower in the SIGMA-Eye, the heat distribution covered a larger volume of the abdomen (in particular the upper abdomen). For the SIGMA-60 applicator the achieved T90 appeared to be limited between 41 and 42 °C, for the SIGMA Eye applicator more effective T90 in the range 42 to 43 °C were obtained.
  
  
  CONCLUSIONS
  Our results suggest that an adequate heating of the abdomen and therefore abdominal regional hyperthermia in PC patients appears feasible. The SIGMA-Eye applicator appears to be superior compared to the SIGMA-60 applicator for abdominal hyperthermia.
authors.affiliation: Department of Radiation Oncology, Charité Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany. marcus.beck@charite.de.
authors.forename: Marcus
authors.initials: M
authors.lastname: Beck
authors.affiliation: Department of Radiation Oncology, Charité Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany.
authors.forename: Pirus
authors.initials: P
authors.lastname: Ghadjar
authors.affiliation: Department of Radiation Oncology, Charité Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany.
authors.forename: Mirko
authors.initials: M
authors.lastname: Weihrauch
authors.affiliation: Charité Comprehensive Cancer Center, Charité Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Susen
authors.initials: S
authors.lastname: Burock
authors.affiliation: Department of Radiation Oncology, Charité Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany.
authors.forename: Volker
authors.initials: V
authors.lastname: Budach
authors.affiliation: Department of Radiation Oncology, Charité Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany.
authors.forename: Jacek
authors.initials: J
authors.lastname: Nadobny
authors.affiliation: Department of Gynecology, Charité Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Jalid
authors.initials: J
authors.lastname: Sehouli
authors.affiliation: Department of Radiation Oncology, Charité Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany. peter.wust@charite.de.
authors.forename: Peter
authors.initials: P
authors.lastname: Wust
mesh_terms: D000005:Abdomen; D002277:Carcinoma / Q000556:secondary / Q000628:therapy*; D003198:Computer Simulation; D006801:Humans; D006979:Hyperthermia, Induced / Q000295:instrumentation* / Q000379:methods*; D010534:Peritoneal Neoplasms / Q000556:secondary / Q000628:therapy*; D010865:Pilot Projects