title: Impact of Age and Primary Disease Site on Outcome in Women With Low-Grade Serous Carcinoma of the Ovary or Peritoneum: Results of a Large Single-Institution Registry of a Rare Tumor.
abstract: OBJECTIVE
  Low-grade serous carcinoma of the ovary (LGSOC) or peritoneum (LGSPC) is a rare subtype of ovarian or peritoneal cancer characterized by young age at diagnosis and relative resistance to chemotherapy. The purpose of this study is to report our updated experience with women diagnosed with LGSOC or LGSPC to assess the validity of our original observations.
  
  
  METHODS
  Eligibility criteria for patients from our database were: stage I to IV LGSOC or LGSPC, original diagnosis before January 2012, and adequate clinical information. All patients were included in progression-free survival, overall survival, and multivariable Cox regression analyses. A subset analysis was performed among patients with stage II to IV low-grade serous carcinoma treated with primary surgery followed by platinum-based chemotherapy.
  
  
  RESULTS
  We identified 350 eligible patients. Median progression-free survival was 28.1 months; median overall survival was 101.7 months. In the multivariable analysis, compared with women age ≤ 35 years, those diagnosed at age > 35 years had a 43% reduction in likelihood of dying (hazard ratio, 0.53; 95% CI, 0.37 to 0.74; P < .001). Having disease present at completion of primary therapy was associated with a 1.78 increased hazard of dying compared with being clinically disease free (P < .001). Similar trends were noted in the smaller patient cohort. In this cohort, women with LGSPC had a 41% decreased chance of dying (hazard ratio, 0.59; 95% CI, 0.36 to 0.98; P = .04) compared with those with LGSOC.
  
  
  CONCLUSIONS
  Women age < 35 years with low-grade serous carcinoma and those with persistent disease at completion of primary therapy have the worst outcomes. Patients with LGSPC seem to have a better prognosis than those with LGSOC.
authors.affiliation: All authors: University of Texas MD Anderson Cancer Center, Houston, TX. dgershen@mdanderson.org.
authors.forename: David M
authors.initials: DM
authors.lastname: Gershenson
authors.affiliation: All authors: University of Texas MD Anderson Cancer Center, Houston, TX.
authors.forename: Diane C
authors.initials: DC
authors.lastname: Bodurka
authors.affiliation: All authors: University of Texas MD Anderson Cancer Center, Houston, TX.
authors.forename: Karen H
authors.initials: KH
authors.lastname: Lu
authors.affiliation: All authors: University of Texas MD Anderson Cancer Center, Houston, TX.
authors.forename: Lisa C
authors.initials: LC
authors.lastname: Nathan
authors.affiliation: All authors: University of Texas MD Anderson Cancer Center, Houston, TX.
authors.forename: Ljiljana
authors.initials: L
authors.lastname: Milojevic
authors.affiliation: All authors: University of Texas MD Anderson Cancer Center, Houston, TX.
authors.forename: Kwong K
authors.initials: KK
authors.lastname: Wong
authors.affiliation: All authors: University of Texas MD Anderson Cancer Center, Houston, TX.
authors.forename: Anais
authors.initials: A
authors.lastname: Malpica
authors.affiliation: All authors: University of Texas MD Anderson Cancer Center, Houston, TX.
authors.forename: Charlotte C
authors.initials: CC
authors.lastname: Sun
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D018284:Cystadenocarcinoma, Serous / Q000473:pathology*; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008875:Middle Aged; D010051:Ovarian Neoplasms / Q000473:pathology*; D010534:Peritoneal Neoplasms / Q000473:pathology*; D011379:Prognosis; D012042:Registries; D016896:Treatment Outcome; D055815:Young Adult