Multidetector computed tomography follow-up of hypoattenuating small liver lesions in patients with rectal cancer.
OBJECTIVE
To study the behavior of hypoattenuating liver lesions, deemed too small to characterize at baseline scanning with multidetector computed tomography (CT), in patients with rectal cancer.


METHODS
Retrospective review of locally advanced rectal cancer patients from a radiation oncology therapy database was conducted. Patients who presented before neoadjuvant chemoradiation without metastases at baseline CT and with follow-up scans for at least 1 year after therapy were evaluated. CT studies were reviewed for the presence and change in size of hypoattenuating liver lesions (<15 mm) at baseline and follow-up.


RESULTS
A total of 616 consecutive patients from the radiotherapy database were reviewed. Of these, 70 patients with a total of 163 hepatic lesions met the selection criteria. The mean patient age was 62.4 years (range, 26-85 years). All patients subsequently underwent surgery and adjuvant chemotherapy. The mean time of radiographic imaging from baseline CT to most recent surveillance CT was 3.3 years (range, 1.1-7.4 years). Two radiologists independently reviewed the CTs. The lesions were stable in 56 of 70 (80.0%, 95% confidence interval: 69%, 89%) patients. Of 163 lesions, 148 (90.8%) were stable, 8 (4.9%) regressed, and 7 (4.3%) progressed in size. No significant difference in results was found for patients stratified according to T-stage (P = 0.41) and N-stage (P > 0.99).


CONCLUSIONS
In patients with rectal cancer, majority of small hypoattenuating liver lesions remain stable and are treated as benign lesions, at multidetector CT follow-up of more than a year. Nevertheless, hepatic lesion stability during systemic therapy should still be interpreted with caution and closely followed for at least 1 year after completion of therapy.
Tan
Cher Heng
CH
Departments of Diagnostic Radiology, University of Texas, MD Anderson Cancer Center, Houston, USA. tchers1977@gmail.com
Bhosale
Priya R
PR
Das
Prajnan
P
Crane
Christopher H
CH
Viswanathan
Chitra
C
Raval
Bharat
B
Eng
Cathy
C
Iyer
Revathy B
RB
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D015331:Cohort Studies; D003131:Combined Modality Therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000556:secondary* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011878:Radiotherapy; D012004:Rectal Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000628:therapy; D012189:Retrospective Studies; D015996:Survival Rate; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome