Washington, Jan 3 (IANS) A new technique will enable physicians to distinguish cancerous lymph nodes from healthy tissue in cancer patients.Researchers from the University of Erlangen-Nürnberg, Germany, used a hybrid single photon emission computed tomography-computed tomography (SPECT-CT) camera to determine and locate the spread of cancer cells to nearby lymph nodes.

The demonstration or exclusion of cancer spread (metastasis) in regional lymph nodes plays a major role in treating the disease since all patients with lymph node metastases are considered to be at high risk for recurrence, the researchers said.

Currently, patients with differentiated thyroid carcinoma (DTC) who have had their thyroid removed are treated with radioactive iodine, which effectively zeros in on and kills any remaining cancerous thyroid cells.

Because one of the functions of the thyroid gland is to absorb iodine from the blood, radioiodine is taken up by any thyroid tissue not removed by surgery, including cancerous cells spreading to other body parts, such as lymph nodes.

In addition to emitting electrons that destroy the tissue harbouring the radionuclide, radioactive iodine emits photons suitable for imaging, said a Erlangen-Nürnberg release.

“Normal thyroid tissue as well as residual cancer cells concentrate radioiodine. Performed after ingestion of radioiodine, SPECT-CT provides three-dimensional images of the distribution of the radionuclide in the human body and is therefore used for staging this type of cancer,” said Torsten Kuwert, co-author of the study.

In the study, 57 patients received radioiodine therapy. Afterwards, a SPECT-CT camera was rotated around the patients at a variety of angles to capture where the radioactivity was occurring.

SPECT imaging can locate cells in the body that are not behaving normally, but does not provide the detailed, X-ray-like images that CT imaging can. The hybrid camera, however, is able to reveal both the malignant cell activity and the exact anatomical location.

According to the American Cancer Society, DTC is the most common form of thyroid cancer and one of the success stories in the war on cancer.

Since the advent of radioiodine therapy, it has been considered one of the more curable cancers. In 2009, about 37,340 new cases of thyroid cancer will be diagnosed in the US. Of the new cases, about 28,410 will occur in women, and 8,930 in men.

These findings were published in the Journal of Nuclear Medicine.