TDT has developed marker tests which utilize RT PCR to amplify the mRNA of a protein called Guanylyl Cyclase C (GCC). Dr. Waldman and his research team have established that GCC is found only in the mucosa of the intestine, and on colorectal cancer cells in extra-intestinal sites. This establishes GCC as a highly selective marker for detecting colorectal cancer metastases. Clinical studies have demonstrated that GCC RT-PCR can detect a single cancer cell in 10,000,000 normal cells.

Tests developed include:

Lymph Node test - Detects metastatic cells in lymph nodes for accurately staging patients.

Blood Monitor test - Detects circulating colorectal cancer cells in patients undergoing post-treatment monitoring for recurrent disease.