The Pap test has become more reliable since its invention nearly 70 years ago by Dr. George Papanicolaou. But one thing scientists still haven’t been able to prevent is human error in reading the smears, which are used to detect several diseases including cervical cancer and herpes.
Experts say patients can take certain precautions to ensure that the diagnosis they receive from their physician, based on Pap smear results, is accurate.
First, if you are worried about a Pap smear that has already been used in a diagnosis, call your doctor.
“Your physician can recall the slides from the laboratory, send it somewhere else and get a second opinion,” said Dr. Wolfgang Fuhs, chief of laboratories for the state Department of Health Services. The state requires labs to keep your specimen on file for five years.
The American Cancer Society recommends that women who are sexually active or older than 18 have a Pap smear once a year for three consecutive years. If the test is consistently negative, then the frequency of taking a Pap test can be decided by doctor and patient, the organization said.
Pap smears are taken by a physician or nurse. A specimen of cervix cells is placed on a stained slide. Cytotechnologists study slides--each containing thousands of cells--under a microscope to detect any signs of abnormal cell growth.
About 60,000 women will get cervical cancer this year and 7,000 will die from it, the society has reported. “It’s tragic that anyone dies from cervical cancer today because we know how to prevent that,” said Dr. Robert Hutter, past president of the cancer society.
Hutter and other pathologists said patients should demand their doctors do background checks on the labs they use to read Pap smears. “You rely on the physicians to use good judgment in sending out laboratory samples,” said Dr. Dorothy Rosenthal, chief of cytology at UCLA Medical Center. “Unfortunately, many physicians are guilty of going for the lowest price, not the best quality.”
Here are some of the questions experts recommend asking:
- How many slides does a cytotechnologist read per year?
Some labs require their employees to read no more than 12,000 slides a year. The number of slides a cytotechnologist reads can be calculated by dividing the lab’s annual volume of slides by the number of cytotechnologists processing those slides. Physicians usually can obtain this information from labs.
- Does the lab have a quality assurance program and re-examine at least 10% of its slides before issuing diagnoses?
- Is the lab holding in-service training for its cytotechnologists?
- Do cytotechnologists earn a salary or are they paid on a per-slide basis?
Paying per slide is troubling to many pathologists because they believe it encourages speed over accuracy. “If your car payment is coming due or you need a new set of tires, you work more,” Rosenthal said.
- Are cytotechnologists allowed to take slides home at night?
If they are, many pathologists advise asking your doctor to find another lab. “There is no way between kids, the dog, the telephone and rug salesmen that you can do a credible job,” Rosenthal said.
If you are experiencing symptoms such as vaginal bleeding, pathologists say you should see your doctor immediately, even if your latest Pap smear came back negative. “If there is any discharge, burning, itching or foul odor, that person needs to get themselves in as quickly as possible for an examination,” Rosenthal said.