title: The changes in residual cancer burden after interval debulking surgery are effective in evaluating the response to adjuvant chemotherapy.
abstract: OBJECTIVE
  To study the clinical significance of the change of residual cancer burden (RCB) of epithelial ovarian carcinoma (EOC) between primary (PDS) and interval debulking surgery (IDS) in order to evaluate the effectiveness of adjuvant chemotherapy.
  
  
  METHODS
  Thirty-eight EOC patients with suboptimal PDS with adjuvant chemotherapy were selected for this retrospective study and divided into pathologically negative (group A) and pathologically positive (group B) groups based on the histopathological examination and the change of size of residual disease after IDS. Patients in group B were further divided into groups B1 (partial remission criteria, n = 9), B2 (consistent with stable disease, n = 12) and B3 (consistent with disease progression, n = 4) based on the changes in RCB between PDS and IDS and the guidelines to evaluate the response to treatment in solid tumors (Response Evaluation Criteria in Solid Tumors, RECIST). The responses to chemotherapy evaluated by pathological examination of RCB versus by CA-125, recurrence patterns, and prognoses were analyzed.
  
  
  RESULTS
  The clinical benefit rates evaluated by pathological assessment for groups A, B1, B2 and B3 were 100, 100, 100 and 0%, respectively (p < 0.01), whereas the rates were not statistically different when evaluated by CA-125 (100, 100, 91.7 and 100%, respectively; p > 0.05). The median progression-free survival (PFS) for patients in groups A and B was 36 and 6 months, respectively (p < 0.05); the median overall survival (OS) was 93 and 42 months, respectively (p < 0.05). There were no significant differences in median PFS or OS among patients in groups B1, B2 and B3 (PFS: 16, 6 and 1.5 months; OS: 52, 31 and 30.5 months, respectively; all p > 0.05), but there were significant differences in median PFS or OS between B1 and B3. There was no significant difference in recurrence rates between groups A and B (53.8 vs. 72.0%, p > 0.05), but there were significant differences in the rate of drug-resistant recurrence [28.6% (2/7) vs. 72.2% (13/18), p < 0.05] and in median PFS of relapsed patients (19 vs. 4 months, p < 0.05).
  
  
  CONCLUSIONS
  The histopathological assessment of RCB between PDS and IDS may be used to evaluate and predict the response to adjuvant chemotherapy in EOC.
authors.affiliation: Department of Gynaecology, Peking University People's Hospital, Beijing, China.
authors.forename: Lili
authors.initials: L
authors.lastname: Kong
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Li
authors.forename: Qiying
authors.initials: Q
authors.lastname: Xu
authors.forename: Lihui
authors.initials: L
authors.lastname: Wei
authors.forename: Jianliu
authors.initials: J
authors.lastname: Wang
authors.forename: Heng
authors.initials: H
authors.lastname: Cui
authors.forename: Shijun
authors.initials: S
authors.lastname: Wang
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhao
mesh_terms: D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000008:administration & dosage; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D018394:CA-125 Antigen / Q000378:metabolism; D000077216:Carcinoma, Ovarian Epithelial; D017024:Chemotherapy, Adjuvant; D002945:Cisplatin / Q000008:administration & dosage; D004317:Doxorubicin / Q000008:administration & dosage; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008875:Middle Aged; D018365:Neoplasm, Residual; D009375:Neoplasms, Glandular and Epithelial / Q000188:drug therapy* / Q000601:surgery; D010051:Ovarian Neoplasms / Q000188:drug therapy* / Q000601:surgery; D017239:Paclitaxel / Q000008:administration & dosage; D011237:Predictive Value of Tests; D012189:Retrospective Studies
chemical_list: D000970:Antineoplastic Agents; D018394:CA-125 Antigen; D004317:Doxorubicin; D017239:Paclitaxel; D002945:Cisplatin