KEMH excited about advanced cervical screening system
Cervical cancer is an almost 100 percent curable disease, but many women in developing countries still succumb to it.
In 2010, there were 11 cases of severe precancerous lesions (carcinomas that cannot spread) in Bermuda and one case of invasive carcinoma (a carcinoma that can or has already spread).
King Edward VII Memorial Hospital (KEMH) is hoping to see these figures fall even further with the introduction of the ThinPrep Imaging System with Dual Review, an advanced cervical screening system.
“We are very excited to offer the ThinPrep system to women in Bermuda,” said Jackie Simons, senior technologist for anatomic pathology. “Each Papanicolaou [Pap] test is now analysed by the new system and then screened by a skilled cytotechnologist. Cells of interest are highlighted for the technologist to review, helping them to better focus their skills on pre-cancerous cells. This new method improves disease detection and enables early treatment interventions to prevent cancer.”
The system is already in common use in the United States and is thought to be the most accurate type of testing currently available for cervical cancers. The Bermuda Hospitals Board (BHB) is the only laboratory in Bermuda offering this process. They handle around 7,500 screenings a year, about half of all screenings done in Bermuda.
“Not everyone’s Pap test comes to the hospital,” said Ms Simons. “[They are] either farmed overseas or sent to KEMH.”
The new ThinPrep system combines advanced computer imaging technology with human expertise to improve cervical cancer screening efficiency and performance. It is the first fully integrated, interactive computer system available to assist the experts in screening Pap test slides. All cervical cancer tests at BHB are now screened using this system.
In general, doctors in Bermuda recommend beginning Pap testing when women become sexually active. Women with certain risk factors may require frequent testing and are encouraged to discuss cervical cancer screening with their healthcare provider. These risk factors include a previous diagnosis of cervical cancer or a Pap test that showed pre-cancerous cells, exposure to diethylstilbestrol (DES) before birth, HIV infection and a weakened immune system due to organ transplant, chemotherapy or chronic corticosteroid use. Women can request their doctor or gynecologists send their Pap tests to the hospital for testing in order to benefit from this new system.
Cervical cancer is almost 100 percent curable if detected early. More than 30 published studies involving more than 500,000 patients have demonstrated improved performance using the ThinPrep system. Improved accuracy of testing means a better chance of early diagnosis and a better outcome for women with cervical cancer.
“The old method was simply that we would receive the cell sample and a cytotechnologist would screen the pap test and diagnose it,” said Ms Simons. “With the imager what you have is advanced computerised technology that will select cells of interest that may be abnormal or atypical cells. It just highlights where they are, but it still needs a human being to look at the test. The combination of this computer technology with qualified cytotechnologists has yielded a more sensitive Pap test where we are able to more effectively find abnormalities.”
Kudzanayi Charakupa, consultant pathologist for anatomical pathology at KEMH, said that typically less than five percent of Pap tests screened come up abnormal.
“We are looking for lesions,” said Dr Charakupa. “Ideally, we would like to catch it at the pre-cancerous stage. The aim is to get the pre-cancerous lesions and identify the patients who need intervention before cancer develops. For pre-cancerous lesions there is no need for radiation, they are just removed by surgery. Depending on how severe, the patient is either closely followed up if they harbour a mild pre-cancerous lesion, or removal by surgery will be performed for severe but pre-cancerous lesions. It is only cancerous cases that need radiation therapy.”
She said the good news is that women in Bermuda tend to be quite well informed about the need for Pap tests and general health screenings. “We are seeing mostly pre-cancerous lesions,” she said. “We are seeing very little of the invasive carcinomas. They are being caught before they become cancers. For those who are not having their annual Pap test, they need to start having them done.”
The pre-cancerous lesions are associated with the human papillomavirus virus (HPV) infection. In Bermudas, like many parts of the world, the HPV infection rate is very high. There is now an HPV vaccine offered that protects against many of the major strains of the HPV virus. The fact that we are seeing very low cervical cancer cases with high HPV infection rates reflects the effectiveness of the local cervical screening programme.
“I believe it is a personal decision whether to have the HPV vaccine,” said Ms Simons. “It is a matter of personal choice. Certainly, one can choose to practise abstinence until such time they have a partner and are in a monogamous relationship. Use of barrier protection during sex is another option, but the vaccine is available.”
Suzanne Berlin, instructor in clinical medicine at Harvard Medical School in the division of gynaecological medical oncology at Dana Farber Cancer Institute in Boston Massachusetts, praised Bermuda’s aggressive approach to screening for cervical cancer. She specialises in gynaecological tumours.
“Because of the aggressive screening done on your Island and in developed countries you don’t see a lot of advanced cases of cervical cancer,” said. “Dana Farber is involved in a big study in South Africa at the moment, because the incidence is high there.”
She said an abnormal Pap test result shouldn’t be interpreted by the patient as a death sentence.
“If you catch it within that continuum before it becomes invasive you have many more options in which to treat it,” she said. “Cancers don’t start as invasive, but become invasive over time. The Pap test and the ThinPrep procedure that has been in place since 1996, has remarkably increased the ability to detect malignancy.”
At Dana Farber, Dr Berlin sees patients who have more invasive cervical tumours that need more aggressive treatment. She said in terms of research the HPV vaccines were a big step in preventing cervical cancer. She said currently there is another study open looking at integrating a drug called Avastin with chemotherapy treatment. Avastin is an antibody therapy and used with chemotherapy,” Dr. Berlin explains. “It has been approved for management of other malignancy such as renal, lung, certain types of brain cancer and breast cancer. There is a study through the Gynecologic Oncology Group studying Avastin in advanced cervix cancers.”
“It is an antibody,” she said. “It has been approved in renal cell cancer, approved for lung cancer, breast cancer and brain cancer. They use it in recurrent treatment for various tumours. As with every chemotherapy agent there is potential for multiple side effects. The drug is still in study. The main thrust for cervical cancer really is the prevention. Once it is found at an advanced stage involving other organs or lymph nodes outside of the pelvis, cure is not possible.
“A big compliment to [BHB] for getting this imaging programme up, because it is a valuable and important tool for patient care and management. It is so important. Cervical cancer is definitely a preventable disease. The more we can deal with prevention, the better for the patient as well as the medical community in general.”