Interesting Cases: GI Series Synchronous rectal and prostate cancer

  • 80 Year old gentlemen, Smoker, DM/type2 and Interstitial lung disease
  • Presented with 5 month history of stool incontinence, bleeding per rectal and pain while passing stool.
  • Sigmoidoscopy showed an ulcerated mass lesion in rectum 5 cm from anal verge
  • Biopsy- Adenocarcinoma

PET CT SCAN : Baseline

FDG avid (SUVpeak:9.3) enhancing eccentric nodular mural thickening along anterior and left lateral wall of distal rectum. Few para rectal Nodes was seen. No other distant metastases.


  • MRI Pelvis- growth in distal rectum from 10 to 5’o clock position over length of 4.6cm located above medial attachment of levator ani. Lesion showed marked restriction with mild post contrast enhancement.
  • Prostate too showed an incidentally detected T2 hypointense signal measuring 16.6 x 9 mm restricted to right lobe in apex and middle lobe (PIRADS V).
  • PSA was 5.7 ng/ml
  • Case was discussed meticulously in tumor Board

Tumor board discussion and treatment challenges

  • TRUS guided prostate biopsy had high chances of tumor bleed because of another tumor in rectum
  • Patient had synchronous adeno carcinoma rectum T3N1M0 and Carcinoma Prostate (T1N0M0)
  • Tumour Board decided to treat patient with curative radiation therapy with IGRT technique for both prostate and rectal cancer
  • Radiation was given daily to rectal disease and lymph node draining nodal stations as well to the prostate over 5 weeks with simultaneously integrated boost (Higher dose) to prostatic lesion. Patient completed radiation without any significant toxicity.

Tumor board discussion and treatment challenges

Target involved the prostatic and rectal cancer

Prostate lesion and rectum were included , prostate getting higher dose than rectum

Follow up at 1 year after treatment

  • Patient did not undergo surgery and was kept on “watch and wait” protocol with close follow up
  • Patient’s bowel bladder habits are normal and totally asymptomatic
  • PET Scan and Sigmoidoscopy at 3 months and 1 year of follow up suggested complete metabolic response and no evidence of disease anywhere in body
  • PSA <0.4 ng/ml at 1 year

PET CT at Baseline

PET CT after 1 year

Take Home Message

  • Non surgical treatment for rectal cancer is possible in selected patients
  • Informed decision making and compliance are important
  • Meticulous tumor board discussion and decision making helps
  • Advanced and precise radiation treatment on most modern equipment
  • Image Guidance and daily cone beam CT before treatment for exact matching
  • Least Possible toxicity to adjacent organs

Post Radiation : 1 year

Sigmoidoscopy at diagnosis and after 1 year of treatment