title: Toward the molecular dissection of peritoneal pseudomyxoma.
abstract: Outcome of pseudomyxoma peritonei (PMP) after cytoreductive surgery (CRS) and hypertermic intraperitoneal chemotherapy (HIPEC) is heterogeneous even after adjusting for clinico-pathological prognostic variables. The identification of additional prognostic or even predictive biomarkers is an unmet clinical need.
  
  
  
  Forty patients with mucinous appendiceal tumors and PMP were clinically eligible and had evaluable tumor samples obtained after CRS and HIPEC. We carried out next-generations sequencing (NGS) of 50 gene's hotspot regions contained in the Hotspot Cancer Panel v2 using the Ion Torrent Personal Genome Machine platform (Life Technologies).
  
  
  
  KRAS and GNAS mutations were found in 72% and 52%, and their allelic frequency was below 10% in 55% and 43% of samples, respectively. KRAS and GNAS mutations were associated with worse progression-free survival (PFS) at univariate analysis (P = 0.006 and 0.011, respectively). At multivariate analysis, only KRAS mutations were independently associated with PFS (P = 0.012); GNAS mutations were not-being significantly associated with other poor prognostic features such as incomplete cytoreduction or KRAS mutations. Validation of results was carried out in an independent bi-institutional cohort of 25 patients and the prognostic effect of KRAS mutations was again confirmed in the multivariate model (P = 0.029). NGS approach allowed the discovery of other potentially druggable mutations such as those in PI3K, AKT, LKB1, FGFR3 and PDGFRA.
  
  
  
  Given the homogeneity of this series and the sensitivity of NGS in this low-cellularity tumor, we demonstrated for the first time a poor prognostic role of KRAS mutations.
authors: Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano, Italy filippo.pietrantonio@istitutotumori.mi.it.
authors: F
authors: F
authors: Pietrantonio
authors: Pathology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano.
authors: F
authors: F
authors: Perrone
authors: Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano, Italy.
authors: A
authors: A
authors: Mennitto
authors: Department of Surgery, Drexel University College of Medicine, Philadelphia, USA.
authors: E M
authors: EM
authors: Gleeson
authors: Pathology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano.
authors: M
authors: M
authors: Milione
authors: Pathology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano.
authors: E
authors: E
authors: Tamborini
authors: Pathology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano.
authors: A
authors: A
authors: Busico
authors: Pathology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano.
authors: G
authors: G
authors: Settanni
authors: Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano, Italy.
authors: R
authors: R
authors: Berenato
authors: Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano, Italy.
authors: M
authors: M
authors: Caporale
authors: Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano, Italy.
authors: F
authors: F
authors: Morano
authors: Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano, Italy.
authors: I
authors: I
authors: Bossi
authors: Pathology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano.
authors: A
authors: A
authors: Pellegrinelli
authors: Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano, Italy.
authors: M
authors: M
authors: Di Bartolomeo
authors: Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano, Italy.|Oncology Department, University of Milan.
authors: F
authors: F
authors: de Braud
authors: Surgery Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano, Italy.
authors: D
authors: D
authors: Baratti
authors: Department of Surgery, Drexel University College of Medicine, Philadelphia, USA.
authors: W B
authors: WB
authors: Bowne
authors: Surgery Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano, Italy.
authors: S
authors: S
authors: Kusamura
authors: Surgery Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano, Italy.
authors: M
authors: M
authors: Deraco
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000235:genetics*; D002864:Chromogranins / Q000235:genetics*; D002945:Cisplatin / Q000008:administration & dosage; D003131:Combined Modality Therapy; D065426:Cytoreduction Surgical Procedures; D018572:Disease-Free Survival; D005260:Female; D019205:GTP-Binding Protein alpha Subunits, Gs / Q000235:genetics*; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D006979:Hyperthermia, Induced; D008297:Male; D008875:Middle Aged; D009154:Mutation; D011379:Prognosis; D016283:Proto-Oncogene Proteins p21(ras) / Q000235:genetics*; D011553:Pseudomyxoma Peritonei / Q000188:drug therapy / Q000235:genetics* / Q000473:pathology / Q000601:surgery
chemical_list: D014408:Biomarkers, Tumor; D002864:Chromogranins; C117307:KRAS protein, human; C406732:GNAS protein, human; D019205:GTP-Binding Protein alpha Subunits, Gs; D016283:Proto-Oncogene Proteins p21(ras); D002945:Cisplatin
keywords: GNAS; KRAS; prognosis; pseudomyxoma peritonei