The prognostic value of micrometastases detected retrospectively by RT-PCR is significant in AJCC stage II colorectal patients. Studies utilizing RT-PCR performed a more complete nodal analysis when compared to studies using IHC techniques. RT-PCR may also be more specific for the detection of clinically relevant micrometastases compared to IHC detected cytokeratins. Prospective studies are needed to evaluate the potential benefit of systemic chemotherapy in patients with molecular metastases.

Introduction-Historically, the treatment of anorectal melanoma has been abdominoperineal resection (APR) but more recently local resection alone. Although treatment at melanoma centers has become less aggressive in the modern era, the adoption of this approach and related outcomes across the United States is unknown.

Since the introduction of sentinel node biopsy in 1990 as a minimally invasive surgical technique for the diagnosis of melanoma lymphatic metastases, the number of applications has expanded. We review applications and the current status of sentinel node biopsy in melanoma, breast, colon, gastric, esophageal, head and neck, thyroid, and lung cancer.Variations on techniques specific to each organ are explained, and the current role of sentinel node biopsy in diagnosis and treatment is discussed.

The sentinel lymph node (SLN) technique has practical applications in multiple solid tumors including colorectal carcinoma. Identifying the SLN(s) provides better staging of the regional lymphatics beyond standard H&E analysis. This additional information assists in predicting biology and may be useful in guiding adjuvant therapy. We postulate the era of sentinel node has ushered in a new generation of node-negative patients; patients that have an exceptionally favorable outcome when compared to historic controls.

This is the first prospective evaluation of the prognostic impact of MM in colorectal cancer. These results indicate that the detection of MM may be clinically relevant in CC and may improve the selection of patients for adjuvant systemic chemotherapy. Patients with CC who are node negative by cumulative detection methods (H&E/IHC and qRT) are likely to be cured by surgery alone.