Cancer Care Associates

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CBC stands for complete blood count and is performed as a blood test. At Cancer Care Associates, the laboratory has the rare ability to perform a CBC by fingerstick and obtain a result within minutes. The test measures the levels of various blood elements including number and subtypes of white blood cells (WBC), quantity of red blood cells (measured as hematocrit (HCT) and hemoglobin (HGB) to assess for anemia), and numbers of platelets. White blood cells fight infection and when low in number place a patient at risk of infection. Red blood cells carry oxygen and when low in number results in fatigue. Platelets prevent or help stop bleeding.

Chemistry panels measure a variety of organ functions. At Cancer Care Associates the chem panel includes measurements of electrolytes, kidney function, nutritional level, and potential damage to the liver and skeletal system. The electrolytes include levels of sodium, potassium, chloride, and carbon dioxide. Kidney function is measured by BUN and creatinine and high levels are undesirable. Albumin, a protein made by the liver, will be low in situations of poor nutritional level or dysfunction of the liver. Liver function tests also include bilirubin, transaminases (AST and ALT), and alkaline phosphatase. Mild elevation of liver tests is common and usually doesn’t indicate disease. Persistently significant elevations are undesirable and require evaluation. Alkaline phosphatase can also be elevated due to skeletal system damage.

Tumor markers are blood tests which when abnormally elevated may indicate cancer activity. The tests measure proteins made by cancer cells which are then released into the blood stream. The proteins differ depending on the cancer and for many cancers no tumor marker test is available. In concept these should be excellent tests. In reality most tumor markers are inaccurate, as they can be elevated for many non-cancer reasons, which differ from test to test, and unfortunately are often at normal levels in the setting of obvious advanced cancer. Therefore normal tumor marker levels do not guarantee that a patient is cancer free, and elevated marker levels do not necessarily indicate a relapse. At this time the most helpful markers are PSA for prostate cancer, and HCG and AFP for cancer of the testis. CA 125 is moderately helpful in monitoring the treatment of ovarian cancer but of limited usefulness in ovarian cancer screening. Unfortunately there are currently no reliable markers for the other common cancers such as breast, lung and colorectal. Markers for breast cancer include CEA, CA 15-3, and CA 27-29. The marker CEA is sometimes used in lung and colon cancer. The marker CA 19-9 is sometimes helpful in pancreatic cancer. As noted above, the markers currently available for these cancers are unable to establish whether or not a patient is cancer free, and are generally considered unreliable as a monitoring tool of cancer status. The exception is when levels are very high in the setting of metastatic disease. In that situation, fluctuations in marker levels may correlate with progress of treatment. Dropping markers generally indicate a favorable response to therapy and rising markers reflect the opposite. The search for more accurate markers is an area of very active research. Learn more >

An ultrasound is an examination usually performed in a radiology department using radiowaves and does not involve Xrays. A probe (transducer) is placed over an area of the body such as the breast or liver, and radiowaves are transmitted through the body part and bounce back and are recorded. An ultrasound can detect an abnormality of a body part and suggest whether or not it is cancer but is not definitive. A biopsy of the abnormality is the only way to establish without doubt that the abnormality is cancer.

During a biopsy procedure a small specimen from the area of concern is removed for examination under the microscope. This can be done with a hollow needle under a local anesthetic using ultrasound or CT guidance, or may be performed through a scope. A number of flexible scopes can be used to guide the biopsy procedure such as an endoscope into the stomach (often referred to as an EGD or upper GI endoscopy), the colon (colonoscopy), the bladder (cystoscopy), or the airways of the lungs (bronchoscopy). Sometimes the biopsy will require the skills of a surgeon and an actual operation. After removal, the specimen is examined by an expert physician (pathologist) to determine if a cancer is present and also often the specific cancer type. This test is the definitive test in establishing that a patient has cancer, and guides the treating physicians in formulating a treatment plan.

This is a test that uses Xrays. CT (or CAT) is an abbreviation for computer axial tomography. Patients lie on a moving platform and enter an Xray machine shaped like a large donut. Within that structure an Xray unit rotates around the patient’s body and images are generated with the use of a computer. This permits a 3 dimensional view of the inside of the body and is particularly valuable in evaluating the lungs and abdominal organs (except for the GI tract). Iodine based contrast is injected intravenously in order to outline blood vessels. Patients with allergies to iodine or shellfish should discuss this with their physician prior to undergoing the injection. Diabetics need to be concerned as well because the iodine contrast can cause damage to the kidneys and a blood test to check for normal creatinine levels should be performed first. Oral medications to lower blood sugar should be omitted for one day. Abdominal and pelvic CT scans give more information when the intestines are outlined by ingesting an oral contrast (barium) before the scan. The most modern CT scan, the spiral CT, can photograph the body from the neck to the pelvis within minutes. Everyone’s body has some variation and therefore not all abnormalities on a CT scan indicate cancer. A specially trained physician called a radiologist will interpret the scan and using well-established criteria, can infer whether an abnormality is cancer. But again a biopsy is the only way to be certain. It is important to note that a CT scan cannot detect cancer that is smaller than 1 cm. A 1 cm cancer represents 1 billion cancer cells. Therefore contrary to popular impression, a normal CT scan doesn’t guarantee that a patient is cancer free.

This is a test that doesn’t use Xrays. MRI stands for magnetic resonance imaging. A patient lies on a moving platform and enters a relatively narrow tunnel that contains a very powerful magnet. A computer generates a 3 dimensional view of the inside of the body by reading changes in the electromagnetic fields of different internal structures that are targeted by the magnet. MRI is particularly useful for evaluating the brain and spinal cord. It is also starting to be used to evaluate the breast. For technical reasons it is less effective in looking within the chest and abdomen although this may change in the near future. Sometimes MRI testing requires contrast injection into the vein with gadolinium. Patients with metallic medical devices such as pacemakers cannot have an MRI. Some patients are afraid of closed spaces, a condition known as claustrophobia, and may require a sedative prior to the scan. Open MRIs are less enclosed but also less accurate in evaluating the brain and spinal cord. As is the case for CT scans, MRI scans aren’t reliable for any one area of cancer that is smaller than 1 cm. As with CT scans, a normal MRI does not guarantee that a patient is cancer free.

This is a nuclear medicine test and should not be confused with a bone density Xray which is used to diagnose osteoporosis. A nuclear medicine bone scan requires the injection of a radioactive substance into the vein which then travels to areas of high bone activity. After several hours pictures are taken with a special camera. Although a bone scan can detect cancer, it also will register areas of bone abnormality due to arthritis, inflammation, infection, and trauma such as current bruises and old fractures. Abnormalities on bone scan require some caution in interpretation. A bone scan cannot detect small areas of involvement by cancer.

A PET scan is short for positron emission tomography and is a nuclear medicine test. A radioactive form of glucose is injected into the vein and the scan measures differences in rate of glucose uptake by different structures within the body. Following injection, the patient lies on a moving platform through a rather open circular structure and a computer generates a 3 dimensional picture. Although a photo is made of the scan for the purpose of placement in a patient’s chart, the scan is actually read on a computer monitor so that the image can be rotated 360 degrees, permitting more accurate interpretation. Not all abnormalities on PET scan result from cancer. Areas of inflammation and infection will also cause scan abnormalities. Diabetics will need to have blood sugar at controlled levels to permit an accurate scan. The PET scan will not detect every cancer and both normal and abnormal scans need caution in interpretation. Cancers smaller than 1 cm may not be detected and therefore a normal scan does not mean that a patient is cancer free.

This is a technique of imaging the breast with Xray. In most cases of breast cancer, the breast tissue has a reaction to the cancer and forms scar tissue and deposition of calcium in a pattern on the mammogram that is determined to be suspicious by the radiologist. Up to 10% of breast cancers will not be detected on mammogram because in those cases, there is no reaction within the breast to having the cancer. Mammograms can detect very small cancers, 1-2 mm in size, about the size of a dot made by a pencil. Postmenopausal women who are not taking estrogen have easier mammograms to interpret compared to women who are still menstruating. Compression or squeezing of the breast is needed for the clearest pictures. Beware of centers claiming low levels of discomfort. Multiple analyses have consistently shown that the most accurate mammograms are performed at the busiest breast centers with the highest volume of patients. Therefore long waiting times in making routine mammogram appointments is a good sign! However all centers will make appointments within 2 weeks for women with a suspicious lump, and that waiting period will not be dangerous.

A bone marrow biopsy permits an analysis of the blood producing tissue within the center of bones. The specimen is usually obtained using a hollow needle placed into the back of the large bone in the pelvic area called the posterior iliac crest using either local anesthetic or conscious sedation. A patient typically lies on his/her stomach and the uppper buttock area is cleaned with iodine and alcohol. Following the administration of the anesthetic a small incision is made into the skin and the needle is inserted. There is generally some mild soreness for 2-3 days. Skin infection or significant bleeding is rare. The specimen is examined by a pathologist under the microscope and special tests can also be performed such as testing for chromosome and DNA abnormalities. Preliminary results can be available in 1-2 days. More extensive analysis can take 2-3 weeks.