title: Prognostic value of histologic tumor regression, thymidylate synthase, thymidine phosphorylase, and dihydropyrimidine dehydrogenase in rectal cancer UICC Stage II/III after neoadjuvant chemoradiotherapy.
abstract: Histologic tumor regression (TR) in rectal cancer after preoperative chemoradiotherapy (CT/RT) may be useful as a surrogate end point for early treatment efficacy, but little is known about its prognostic value. The aim of this follow-up study was to evaluate whether TR is able to predict prognosis in rectal cancer patients. Furthermore, the prognostic value of thymidylate synthase (TS)-gene, thymidine phosphorylase (TP)-gene, and dihydropyrimidine dehydrogenase (DPD)-gene expression after neoadjuvant CT/RT was determined. Forty patients with rectal cancer cUICC stage II/III, receiving preoperative 5-fluorouracil (5-FU) based CT/RT were studied for therapy-induced TR and categorized as "responders" or "nonresponders" according to their TR-grade. Posttherapeutical TS-gene, TP-gene, and DPD-gene expression on surgical resection specimens was quantified by TaqMan real-time PCR after microdissection. During a median follow-up of 58 months, cancer recurrence occurred in 28%. A significant correlation was seen between disease-free survival and lymph node status (P<0.001). All patients, who developed cancer recurrence had a posttherapeutical positive lymph node status. The majority of patients with cancer recurrence were "responders" (91%) after CT/RT. There was a significant correlation between posttherapeutical TS-gene expression and cancer recurrence within the subgroup of "responders." TS-gene expression was significantly higher in patients with cancer recurrence than in those, who are disease-free up to date (P=0.028). In conclusion, lymph node status remains the most important prognostic marker in rectal cancer patients, whereas posttreatment TR by itself has no prognostic significance. Furthermore, measurement of posttherapeutical TS-gene expression may help to identify patients at higher risk for cancer recurrence.
authors.affiliation: Institute for Pathology, University of Technology, Dresden, Germany. Christiane.Jakob@uniklinikum-dresden.de
authors.forename: Christiane
authors.initials: C
authors.lastname: Jakob
authors.forename: Torsten
authors.initials: T
authors.lastname: Liersch
authors.forename: Wolfdietrich
authors.initials: W
authors.lastname: Meyer
authors.forename: Gustavo B
authors.initials: GB
authors.lastname: Baretton
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Schwabe
authors.forename: Peter
authors.initials: P
authors.lastname: Häusler
authors.forename: Bettina
authors.initials: B
authors.lastname: Kulle
authors.forename: Heinz
authors.initials: H
authors.lastname: Becker
authors.forename: Daniela E
authors.initials: DE
authors.lastname: Aust
mesh_terms: D000964:Antimetabolites, Antineoplastic / Q000627:therapeutic use; D042943:Dihydrouracil Dehydrogenase (NADP) / Q000235:genetics*; D018572:Disease-Free Survival; D005260:Female; D005472:Fluorouracil / Q000627:therapeutic use; D005500:Follow-Up Studies; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D042282:Microdissection; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D016133:Polymerase Chain Reaction; D011379:Prognosis; D012004:Rectal Neoplasms / Q000201:enzymology / Q000401:mortality* / Q000473:pathology / Q000628:therapy; D013939:Thymidine Phosphorylase / Q000235:genetics*; D013940:Thymidylate Synthase / Q000235:genetics*
chemical_list: D000964:Antimetabolites, Antineoplastic; D042943:Dihydrouracil Dehydrogenase (NADP); D013940:Thymidylate Synthase; D013939:Thymidine Phosphorylase; D005472:Fluorouracil