Colorectal Cancer Stem Cells Marker Expression in Rectal Cancer Patients Undergoing Chemoradiotherapy-A Pilot Study
- To obtain the distribution of stem cell markers (CD166, CD44, and ESA) in tumor tissue
samples before and after neoadjuvant chemoradiotherapy (NCRT) in patients with stage II
or III rectal cancer.
- To correlate disease-free survival after NCRT with baseline expression and change in
expression of stem cell markers (CD166, CD44, and ESA) after NCRT.
- To correlate baseline and post-NCRT expression of all three stem cell markers (CD166,
CD44, and ESA) with circulating tumor cell (CTC) count and stem cell marker expression
on CTC at baseline and after NCRT.
OUTLINE: Patients receive chemotherapy according to the treating physician's choice and
undergo concurrent radiotherapy over approximately 6 weeks. Between 6-8 weeks after
completion of neoadjuvant chemoradiotherapy (NCRT), patients undergo low anterior or
abdominoperineal surgical resection. Some patients may then receive additional chemotherapy.
Tumor tissue samples are obtained via sigmoidoscopy-guided biopsies at baseline and at the
time of surgery. Blood samples are also collected at baseline and after completion of NCRT.
Samples are isolated for RNA analysis of CD44, CD166, and ESA expression by quantitative
reverse transcriptase-PCR and IHC.
After completion of study treatment, patients are followed up every 3 months for 2 years and
then every 6 months for 3 years.
Masking: Open Label, Primary Purpose: Treatment
Estimation of stem cell markers with stated precision
Bhaumik B. Patel, MD
Barbara Ann Karmanos Cancer Institute
United States: Federal Government