Cancer Diagnosis - Stereotactic Biopsy

Not all tumors are cancer, but all abnormal tissue growths are at least unsettling. Many tumors are discovered on a routine X-ray or perhaps palpated by a physician during a routine physical examination. Some tumors can be ruled non-cancerous simply by the way the feel or look on a radiological film. Other tumors, however, are not so easily dismissed. In cases where the issue of cancer is equivocal, a sample of the tissue—a biopsy—must be taken of the tissue. But what if the tumor is located in a part of the body that should be spared as much as possible, like breast or brain? When possible cancer grows in a precious location, great effort is made to take only as much tissue as necessary and to make sure part of the tumor is dissected during the biopsy. Under these circumstances a stereotactic biopsy is usually performed.

 

 

A stereotactic biopsy is one in which tissue is harvested using some sort of visual guidance, such as a fluoroscope or MRI. A stereotactic biopsy may also involve a frame into which the patient is placed so that very precise placement of the biopsy instrument can be made. Consider a brain tumor, for example. When surgery is not going to be used to make the diagnosis, a stereotactic biopsy may be used to obtain a small amount of tissue. In a stereotactic biopsy for a brain tumor, the patients head is placed in a stereotactic frame and a CT or MRI is performed. Because the stereotactic frame is calibrated, the exact location of the tumor can be determined in all three axes of space. Using the same stereotactic frame, a small needle is advanced to the tumor and a portion of the abnormal tissue is removed. Obviously the path of the needle needs to be guided through less important regions of brain so as to reduce the possibility of unwanted neurological side effects. A stereotactic biopsy of the brain can provide useful information about a brain tumor without subjecting the patient to brain surgery.

 

Stereotactic biopsy can also be done for breast cancer diagnosis using a mammogram or ultrasound to precisely locate the tumor. This stereotactic biopsy approach is particularly useful for core needle biopsy procedures of the breast. Since the accuracy of the results of the core needle biopsy of the breast rely solely on a representative sample of the breast tumor being removed, having radiographic proof that the sample came from the tumor is critical.

 

Stereotactic biopsy has greatly improved prostate cancer diagnosis, also. The prostate gland is important for a number of functions in men; having an intact prostate can lead to a greatly improved quality of life compared to those men who have had a prostatectomy. Prostate cancer, the most common cancer in men, threatens the health of the prostate and the well being on millions of Americans. Accurate diagnosis of prostate cancer requires systematic sampling of the prostate. By using stereotactic biopsy, all regions of the prostate can be sampled which greatly improves diagnostic accuracy. At the same time, the function of the prostate can be preserved by using a stereotactic biopsy approach.