title: Acute Toxicity and Tumor Response in Locally Advanced Rectal Cancer After Preoperative Chemoradiation Therapy With Shortening of the Overall Treatment Time Using Intensity-Modulated Radiation Therapy With Simultaneous Integrated Boost: A Phase 2 Trial.
abstract: This phase 2 study investigated the efficacy and safety of preoperative intensity modulated radiation therapy with a simultaneous integrated boost (IMRT-SIB) without dose escalation, concomitant with standard capecitabine chemotherapy in locally advanced rectal cancer.
  
  
  
  Between January 2014 and March 2015, 51 patients with operable stage II-III rectal adenocarcinoma received preoperative IMRT with pelvic dose of 41.8 Gy and simultaneously delivered 46.2 Gy to T2/3 and 48.4 Gy to T4 tumor in 22 fractions, concomitant with capecitabine, 825 mg/m2/12 hours, including weekends. The primary endpoint was pathologic complete response (pCR).
  
  
  
  Fifty patients completed preoperative treatment according to the protocol, and 47 underwent surgical resection. The sphincter preservation rate for the low rectal tumors was 62%, and the resection margins were free in all but 1 patient. Decrease in tumor and nodal stage was observed in 32 (68%) and 39 (83%) patients, respectively, with pCR achieved in 12 (25.5%) patients. There were only 2 G ≥ 3 acute toxicities, with infectious enterocolitis in 1 patient and dermatitis over the sacral area caused by the bolus effect of the treatment table in the second patient.
  
  
  
  Preoperative IMRT-SIB without dose escalation is well tolerated, with a low acute toxicity profile, and can achieve a high rate of pCR and downstaging.
authors.affiliation: Division of Radiotherapy, Institute of Oncology, Ljubljana, Slovenia. Electronic address: jbut@onko-i.si.
authors.forename: Jasna
authors.initials: J
authors.lastname: But-Hadzic
authors.affiliation: Division of Radiotherapy, Institute of Oncology, Ljubljana, Slovenia.
authors.forename: Franc
authors.initials: F
authors.lastname: Anderluh
authors.affiliation: Division of Surgery, Institute of Oncology, Ljubljana, Slovenia.
authors.forename: Erik
authors.initials: E
authors.lastname: Brecelj
authors.affiliation: Division of Surgery, Institute of Oncology, Ljubljana, Slovenia.
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Edhemovic
authors.affiliation: Division of Radiotherapy, Institute of Oncology, Ljubljana, Slovenia.
authors.forename: Ajra
authors.initials: A
authors.lastname: Secerov-Ermenc
authors.affiliation: Division of Radiotherapy, Institute of Oncology, Ljubljana, Slovenia.
authors.forename: Rihard
authors.initials: R
authors.lastname: Hudej
authors.affiliation: Division of Radiotherapy, Institute of Oncology, Ljubljana, Slovenia.
authors.forename: Ana
authors.initials: A
authors.lastname: Jeromen
authors.affiliation: Division of Surgery, University Medical Centre Maribor, Maribor, Slovenia.
authors.forename: Miran
authors.initials: M
authors.lastname: Kozelj
authors.affiliation: Division of Surgery, University Medical Centre Maribor, Maribor, Slovenia.
authors.forename: Bojan
authors.initials: B
authors.lastname: Krebs
authors.affiliation: Division of Radiotherapy, Institute of Oncology, Ljubljana, Slovenia.
authors.forename: Irena
authors.initials: I
authors.lastname: Oblak
authors.affiliation: Division of Surgery, University Medical Centre Lubljana, Ljubljana, Slovenia.
authors.forename: Mirko
authors.initials: M
authors.lastname: Omejc
authors.affiliation: Division of Diagnostics, Institute of Oncology, Ljubljana, Slovenia.
authors.forename: Andrej
authors.initials: A
authors.lastname: Vogrin
authors.affiliation: Division of Radiotherapy, Institute of Oncology, Ljubljana, Slovenia.
authors.forename: Vaneja
authors.initials: V
authors.lastname: Velenik
mesh_terms: D000230:Adenocarcinoma / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery / Q000628:therapy*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001003:Anal Canal; D000964:Antimetabolites, Antineoplastic / Q000008:administration & dosage* / Q000009:adverse effects; D000069287:Capecitabine / Q000008:administration & dosage* / Q000009:adverse effects; D059248:Chemoradiotherapy / Q000009:adverse effects*; D019583:Dose Fractionation, Radiation; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D059351:Organ Sparing Treatments / Q000379:methods; D057234:Preoperative Period; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects / Q000379:methods*; D012004:Rectal Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery / Q000628:therapy*; D013997:Time Factors
chemical_list: D000964:Antimetabolites, Antineoplastic; D000069287:Capecitabine