title: Multidetector computed tomography follow-up of hypoattenuating small liver lesions in patients with rectal cancer.
abstract: 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.
authors.affiliation: Departments of Diagnostic Radiology, University of Texas, MD Anderson Cancer Center, Houston, USA. tchers1977@gmail.com
authors.forename: Cher Heng
authors.initials: CH
authors.lastname: Tan
authors.forename: Priya R
authors.initials: PR
authors.lastname: Bhosale
authors.forename: Prajnan
authors.initials: P
authors.lastname: Das
authors.forename: Christopher H
authors.initials: CH
authors.lastname: Crane
authors.forename: Chitra
authors.initials: C
authors.lastname: Viswanathan
authors.forename: Bharat
authors.initials: B
authors.lastname: Raval
authors.forename: Cathy
authors.initials: C
authors.lastname: Eng
authors.forename: Revathy B
authors.initials: RB
authors.lastname: Iyer
mesh_terms: 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