All things considered, here is what’s new with cervical cancer. Generally speaking, a number of new research findings are ready to transition into clinical practice.
Here are some examples: Genotyping with DNA amplification was in use to analyze the subtypes of human papilloma virus (HPV) in scrapings and biopsy samples from patients with or without cervical cancer (Ref.3). All in all, HPV is a high risk factor for cervical cancer. Laboratory physicians can use the technique of genotyping to identify the transmission of the virus. This technique also can track the subtypes of HPV, particularly the ones that cause cervical cancer. This procedure is very sensitive. In essence, it can detect abnormal cells as much as two years before it would be seen in biopsy material with conventional Pap tests showing as atypical cells.
Here are some points worth noting:
Chemotherapy
Chemotherapy can improve survival of patients with cervical cancer. However, often the toxic side-effects on the bone marrow can limit its usefulness. Ref. 4 researched the use of low-dose cisplatin in combination with gemcitabine as a chemotherapy, given in weekly intervals. As a result patients with advanced cancer of the pelvis with extensive pelvic metastases survived 36% after 15 months and another 36% had a partial response. The authors noted that this low dose combination had a remarkable lack of bone marrow toxicity, but had a good clinical response. Altogether the researchers had to give on average 10 treatment courses.
Radiotherapy
Given these points, radiotherapy, as shown above, is useful for treatment of early stages of cervical cancer. However, Ref. 5 showed that “concomitant boost accelerated radiotherapy” can give even better results. It does so by optimizing the delivery of optimal radiation to where the tumor cells are in the pelvis and the para-aortic regions. In short, the radiologist achieves this using fractionated radiotherapy treatments to the tumor, the pelvic region and by using brachytherapy (radioactive caesium implants) as well. On balance, the specialist can even treat micro-metastases before they have a chance of becoming larger and reduce survival.
Late complications of radiotherapy
To explain, for a small percentage of patients radiotherapy can have serious late complications. In the long run, one of the serious late side-effects is the development of a radiation induced sarcoma. Ref. 6 examined 5 such cases. They all developed in the pelvic bone behind the sacroiliac joint. The latent period was 5 years or more following the radiation therapy. CT and MRI scans were utilized in evaluating the extent of the tumor. Treatment is like any other bone tumor.
Chemoprevention versus vaccination with HPV vaccine
Chemoprevention is something that works for breast cancer with Tamoxifen. In brief, for cervical cancer a similar approach is a new concept. Ref. 7 examines the possibility to exploit the strong correlation between human papilloma virus (HPV) infection and cervical cancer. These authors are suggesting that it should be possible to prevent a lot, if not all of cervical cancers through treatment of the HPV viruses with ongoing antiviral antibiotics.
HPV Vaccination
HPV vaccine for cervical cancer prevention
Here is a thought-provoking article that examines the implications of an HPV vaccine that is being manufactured by GlaxoSmithKline and also by Merck. If this is used in young girls before they are sexually active, it could prevent millions of cervical cancer cases in the world. However, there have been some negative reactions about the vaccine, reports that the vaccine stings when injected. And recently some deaths were reported, but it is not clear whether or not that was vaccine related. Although I had a different opinion in the past, my opinion now is that it is safer to give the vaccine than not to give it.
Safety of HPV vaccine
On the whole the vaccination program will save lives from reduced mortality of cervical cancer in the long run. Now about 35 million doses of Gardasil have been given to girls and women in the US. This web site gives a clear pictorial display about the safety of the vaccine. In the meantime it is clear that the so-called “deaths” initially reported were not related to the vaccine at all.
Natural progesterone
Natural progesterone has beneficial effects on precancerous cells, at least in a mouse model. But a clinical trial in women using vaginal progesterone cream failed to show the same effect. As a matter of fact, the atypical cells of the cervix were made worse with the progesterone. It likely is not effective for prevention of cervical cancer or for treatment. It remains to be seen whether it would make sense to be combined with all of the other treatment modalities as described or not.
Summary
Despite all of the progress in the treatment of cancer of the cervix, the statistics of longterm survival remain poor for the further advanced cancer with local and distant metastases. It is clear that the deeper the invasion at the time of diagnosis, the higher the %-age of metastases and the less the longterm survival. Early diagnosis or better still, prevention by regular Pap tests and pelvic exams, will lead to the goal of a cure for cancer of the cervix. Eventually immunization of both males and females on a large population base will prevent further unnecessary mortality of women from cancer of the cervix.
More info on vaccination for cervical cancer prevention:
CDC: http://www.cdc.gov/hpv/vaccine.html
World Health Organization: http://www.who.int/bulletin/volumes/85/2/07-020207/en/index.html
References
1. Cancer: Principles &Practice of Oncology.4th edition. Edited by Vincent T. DeVita, Jr. et al. Lippincott, Philadelphia,PA, 1993. Chapter on gynecological tumors.
2. Cancer: Principles&Practice of Oncology. 5th edition, volume 1. Edited by Vincent T. DeVita, Jr. et al. Lippincott-Raven Publ., Philadelphia,PA, 1997. Chapter on gynecological tumors.
3. WG Quint et al. J Pathol 2001 May;194(1):51-58.
4. A Duenas-Gonzalez et al. Am J Clin Oncol 2001 Apr;24(2):201-203.
5. BD Kavanagh et al. Am J Clin Oncol 2001 Apr;24(2):113-119.
6. K Nakanishi et al. Skeletal Radiol 2001 Mar;30(3):132-137.
7. M Follen et al. Cancer 2001 May 1;91(9):1758-1776.
