ROSEMONT, Illinois – Sentinel node biopsy, a technique used to determine whether breast cancer or melanoma (a type of skin cancer) has spread to the lymph nodes, now shows potential in the staging of head and neck cancers, according to a study published in the August issue of the Journal of Oral and Maxillofacial Surgery.

Lymph nodes, small, bean-shaped organs located throughout the body, including the neck, filter bacteria and other invading organisms from the lymphatic system, a part of the immune system that helps fight infections and cancers. The sentinel node (SN) is the first lymph node to receive drainage from a cancerous tumor.

If a SN biopsy does not show cancer cells, there is a greater chance the cancer has not metastasized. If a SN does contain cancer cells, other lymph nodes may also be removed and analyzed to see how far the cancer has spread. This process, known as staging, is essential for planning treatment and making a prognosis.

The relatively non-invasive SN technique could spare many patients the ordeal of a neck dissection, a major open surgery performed under general anesthesia involving the removal of lymph nodes and other tissues suspected or known to contain cancer, says co-author Celine Dekeister, MD, a resident in the department of oral and maxillofacial surgery at Purpan Hospital in Toulouse, France.

While the presence of metastases remains the most important factor in making a prognosis for patients with cancers of the head and neck, the current standard for determining lymph node involvement of head and neck tumors when MRIs, CT scans and clinical examinations are negative is an invasive neck dissection that damage the nerves controlling shoulder movement and impair the lymphatic drainage system, an important part of the immune system that may actually have a protective effect in these types of tumors.

"The SN technique could provide a less invasive, less debilitating alternative to standard surgery," Dr. Dekeister says.

In a prospective study of patients with squamous cell cancer of the oral cavity and oropharynx (back of the throat), SN identification enabled oral and maxillofacial surgeons to stage 6 of 7 patients (86%) found by neck dissection to have positive lymph node involvement.

An estimated 10 to 30 percent of patients with tumors of the oral cavity and oropharynx have lymph node involvement even when the metastases cannot be felt or seen with MRIs or CT scans. Recent research suggests this number actually may be higher. "These findings explain the need for an alternative to a surgical procedure that is often useless and sometimes leads to undesirable sequelae, profoundly affecting the lymphatic system," she says.

"Lymphoscintigraphic SN detection may have a role in the management of squamous cell carcinoma of the head and neck," says Dr. Dekeister, "but prospective, randomized clinical trials are necessary before recommending the technique for widespread use."

SOURCE: American Association of Oral and Maxillofacial Surgeons

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