Patterns of locoregional recurrence after surgery and radiotherapy or chemoradiation for rectal cancer.
OBJECTIVE
To identify patterns of locoregional recurrence in patients treated with surgery and preoperative or postoperative radiotherapy or chemoradiation for rectal cancer.


METHODS
Between November 1989 and October 2001, 554 patients with rectal cancer were treated with surgery and preoperative (85%) or postoperative (15%) radiotherapy, with 95% receiving concurrent chemotherapy. Among these patients, 46 had locoregional recurrence as the first site of failure. Computed tomography images showing the site of recurrence and radiotherapy simulation films were available for 36 of the 46 patients. Computed tomography images were used to identify the sites of recurrence and correlate the sites to radiotherapy fields in these 36 patients.


RESULTS
The estimated 5-year locoregional control rate was 91%. The 36 patients in the study had locoregional recurrences at 43 sites. There were 28 (65%) in-field, 7 (16%) marginal, and 8 (19%) out-of-field recurrences. Among the in-field recurrences, 15 (56%) occurred in the low pelvis, 6 (22%) in the presacral region, 4 (15%) in the mid-pelvis, and 2 (7%) in the high pelvis. Clinical T stage, pathologic T stage, and pathologic N stage were significantly associated with the risk of in-field locoregional recurrence. The median survival after locoregional recurrence was 24.6 months.


CONCLUSIONS
Patients treated with surgery and radiotherapy or chemoradiation for rectal cancer had a low risk of locoregional recurrence, with the majority of recurrences occurring within the radiation field. Because 78% of in-field recurrences occur in the low pelvic and presacral regions, consideration should be given to including the low pelvic and presacral regions in the radiotherapy boost field, especially in patients at high risk of recurrence.
Yu
Tse-Kuan
TK
Department of Radiation Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA.
Bhosale
Priya R
PR
Crane
Christopher H
CH
Iyer
Revathy B
RB
Skibber
John M
JM
Rodriguez-Bigas
Miguel A
MA
Feig
Barry W
BW
Chang
George J
GJ
Eng
Cathy
C
Wolff
Robert A
RA
Janjan
Nora A
NA
Delclos
Marc E
ME
Krishnan
Sunil
S
Das
Prajnan
P
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017024:Chemotherapy, Adjuvant; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000401:mortality* / Q000517:prevention & control*; D011878:Radiotherapy / Q000451:nursing*; D012004:Rectal Neoplasms / Q000401:mortality* / Q000601:surgery / Q000628:therapy*; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D016019:Survival Analysis; D015996:Survival Rate; D013781:Texas / Q000453:epidemiology; D017211:Treatment Failure