New test to diagnose ovarian cancer?
On the occasion of the 136th Papanikolaou, Google celebrates the doctor with its own icon. A new test for the effective diagnosis of uterine cancer and ovarian cancer has been developed, which is based on the old Pap test.
In a study by the Johns Hopkins Kimmel Cancer Center in Baltimore, researchers have successfully tested a test for the early detection of uterine cancer and ovarian cancer that massively improves the treatment of the diseases. The test builds on the well-known Pap test. The results of the study were published in the English-language journal "Science Translational Medicine".
What is the Pap test?
Georgios N. Papanikolaou (1883-1962) was born in Greece. The doctor developed the world-famous Pap test. With this test, it is possible to diagnose cervical cancer and the preliminary stages of the disease. Unfortunately, the test often does not identify ovarian cancer until very late. This cancer often grows unnoticed and initially does not show any typical symptoms. The disease is usually only recognized when the tumor has already spread in the abdomen. The Robert Koch Institute (RKI) writes on this topic "The survival prospects of patients with ovarian cancer are rather poor compared to patients with other cancers of the genital organs." Ovarian cancer affects older women and often leads to death. Less than half of the sick people survive the first five years after diagnosis of the disease.
There is no effective early diagnosis procedure
The biggest problem with the treatment of ovarian cancer is that there is no effective early detection method available for ovarian tumors. This means that the disease cannot be recognized early enough so that there is still a relatively good chance of successful treatment. Of course, attempts to develop such an early detection method have been made several times, for example with the help of ultrasound or certain tumor markers, unfortunately so far always in vain. Successful early identification of ovarian cancer could massively improve healing and treatment for this form of cancer. Researchers have now managed to take an important step closer to such a screening. This screening procedure can also be used for the early detection of uterine cancer.
Who was Georgios N. Papanikolaou?
Papanikolaou, who was born on the Greek island of Evia in 1883 and completed his medical studies at the age of 21, emigrated to the USA after the First World War to do research with his wife. Through his discovery, the spread of cervical cancer was severely restricted. In 1928 he invented the so-called Papanikolaou (Pap) smear, which is still routinely used today to enable early diagnosis of cervical cancer. The test significantly reduced fatal courses of the disease, and the number of women dying from it fell by as much as two thirds.
How reliable was the test?
For the test, the gynecologist smears cells from the cervix and from the cervical canal. Further tests in the laboratory must then determine whether there is an inflammation or pathological change. Occasionally, such a smear also contains cells of the uterine body and ovaries. The researchers suspected that this fact could be used to detect not only normal but also degenerated cells in the smear in the case of uterine or ovarian cancer. They therefore examined tumor tissue from 46 patients with various stages of the disease, 24 of whom had uterine cancer and 22 had ovarian cancer. Then it was analyzed which mutations occurred in the cancer cells of the patients and whether changes also occurred in cells that came from the smear of the women. The disease was demonstrated in all 24 patients with endometrial cancer. In contrast, the rate for ovarian cancer was only 41 percent.
New test checks twelve typical mutations
However, the researchers were able to identify twelve genes in their work, which mutated more frequently in both types of cancer. So a genetic test was developed that can detect these twelve typical mutations. The new test detected a disease in twelve patients with endometrial cancer and two women with ovarian cancer, but it always showed a negative result in the control group.
Cervical cancer was identified with 100 percent accuracy
In honor of Papanikolaou, the new test was called PapGene test. This test is based on an otherwise usual removal of cell material from the cervix, which is not a problem for women. In addition, DNA analysis to identify possible mutations was also easy to carry out. When diagnosed with uterine cancer, the test achieved an impressive 100 percent success rate. Further research should now focus on increasing the so-called sensitivity, since the test identified ovarian cancer with an accuracy of only about 40 percent.
How can the sensitivity of the test be improved?
It could improve the sensitivity of the test if it is performed at different times in the menstrual cycle, if the examination brush is inserted deeper into the cervical canal and a larger number of genome regions are taken into account. Fortunately, the test already misdiagnoses none of the healthy women as positive. This has been a common problem with previous approaches to ovarian cancer detection. Further research is now urgently needed to determine whether the new method can be used as a screening method. (as)