A reader posted a comment on one of my blogs and asked "What tests positively determines prostate cancer?" It prompted me to do a little research. 80 percent of men over 70 years old will get prostate cancer. That is a devastating statistic. A lot of times in the medical field diagnosing something requires a multitude of tests to rule out things and to get a better diagnosis. Such is the case for prostate cancer.

There are several tests used to diagnose prostate cancer. Blood tests, rectal exams, rectal ultrasounds, needle biopsy, and cystoscopy. A high level of PSA in the blood can be a sign of prostate cancer. PSA is a protein produced by cancerous prostate cells. With a rectal exam your doctor can feel for lumpy or a hard prostate. If a lump or hardening is found then most often they will do a needle biopsy to examine under a microscope. A cystoscopy is an examination of your bladder and uretha but can help determine several types of cancer and not just bladder cancer.

With all kinds of cancer, it is important to stay up to date with yearly exams for prevention. I hope this information helps.

Radioactive cancer patients attending this weekend's Super Bowl in Miami could be in for an alarming experience when they pass through radiation detectors designed to signal the presence of dirty bombs. Such cancer patients -- who have received treatment using radioisotopes and still may have tiny amounts of radioactive material in their bodies -- may want to come armed with letters from their doctors explaining their precarious set of circumstances.

The use of radioisotopes in medicine is growing -- and so is the use of radiation detectors in our security-conscious nation, which means patients are triggering alarms when they are not even aware they are being scanned, doctors and security officials say.

Nearly 60,000 people a day in the United States undergo treatment or tests that leave traces of radioactive material in their bodies, according to the Society of Nuclear Medicine. These traces are not enough to hurt anyone, but they are enough to trigger radiation alarms for up to three months.

Radioisotopes are commonly used to diagnose and treat certain cancers and thyroid disorders, to analyze heart function, and to scan bones and lungs. And many doctors already know to equip their patients with travel cards because of the problems they can encounter in public places.

Nearly 20 million nuclear medical procedures were performed in the United States in 2005 -- up 15 percent from 2001. Clearly, the number of people who could be mistaken for terrorists is quite large. So if you are one of these people -- with the power to create a buzz in a public setting -- get your papers in order so you can quickly confirm your identity as nothing more than a cancer patient.

Researchers from Dartmouth Medical School say they have a new way of identifying a deadly form of breast cancer that plagues 17 to 37 percent of all breast cancer patients and mostly premenopausal black women.

Identification comes in the form of locating the marker nestin -- a long filamentous protein indicating the presence of basal epithelial tumors -- which makes this type of cancer hard to diagnose and hard to treat. It also puts patients at high risk for recurrence, marked by a very short time between treatment and relapse.

"Ideally, a marker like nestin would enable clinicians to monitor these patients through frequent tests of a biomarker and, in doing so, detect the cancer before it has a chance to come back," says one professor.

Researchers must now find an effective means of detecting nestin in a clinical screening setting. It won't be as simple as a blood test -- but a non-invasive collection of mammary duct samples may enable the development of a screening tool for at-risk patients.

Technology has come a long way over the years -- and now the technology behind digital mammography is allowing life-saving screenings for the toughest patients to diagnose with breast cancer.

This is no small technological breakthough. It is a critical component for lowering the breast cancer death rate the American Cancer Society reports has declined 2.3 percent each year between 1990 and 2002. Since breast cancer is a treatable disease if caught early, digital mammography will up the odds of survival for women with this disease.

Digital mammography operates according to a computer-based technique that allows for digital manipulation of a breast X-ray. It exceeds the capability of film mammography -- and is much like the comparison between digital photography versus film photography. Both work. But one works better.

Studies show digital mammograms have a lot to offer. They detect tumors better in young women with dense breast tissue, for example. They allow for ease of storage and retrieval of images. And they can easily become part of a woman's electronic medical record.

There are still benefits of traditional mammography and women are still urged to use this less expensive option. They are also urged to conduct self-breast exams and to report for clinical exams with physicians. It's the whole package that contributes to comprehensive breast health, not just one isolated test. When used in combination with all other screening methods, digital mammography makes for a more accurate overall picture.