Oral Bacteria Found Predominantly Associated with Human Colorectal Cancer Cells

By Ramadhani Chambuso

The same oral commensal bacterium and gum disease pathogen called Fusobacterium nucleatum was found to be predominantly associated with primary human colorectal cancer cells and even in distant metastatic lesions, a study published in 2017 on the journal Science, reports. Furthermore, it was proven in mice with colon cancer that after treatment with antibiotics, Fusobacteruim load, cancer cell proliferation and overall tumour growth, all were reduced, which indicates that this organism may play a crucial role in colon cancer development.

Despite other studies suggesting the possible pro-tumorigenic role of Fusobacterium which may include modulation of host immune response to cancer cells and further enhancement of tumour cell invasion in colon cancer pathogenesis, this new study was scientifically able to show the correlation between decrease in Fusobacterium load and the decreased in rate of tumour growth and improved overall patient survival.

Although it is not clear yet if good oral hygiene would probably add advantage to preventive measures to colorectal cancer outcome, these scientists recommended the use of antibiotic Metronidazole, Fusobacterium–specific antimicrobial agents or phage therapy concurrently in colon cancer treatment. This is because broad-spectrum antibiotics may risk other gut microbial balance and did not show any additional effects on tumour growth control in their study.

Source: Bullman et al. (2017), Mima et al. (2015).

Hormonal Contraceptives may Increase a Woman’s Risk of Breast Cancer

By Ramadhani Chambuso

The risk of breast cancer was elevated among women who used hormonal contraceptives than among women who had never used them before, a study suggests, published in December, 2017 on the top journal in human Medicine, New England Journal of Medicine.

The study was done in Denmark, followed up 1.8 million women for 10.9 years who used hormonal birth control methods and only 11,517 cases of breast cancer occurred. Furthermore, when compared with women who have never used any hormonal control pills, the risk of breast cancer increased up to 38% depending on duration of use from less than 1 year to more than 10 years in all forms of hormonal contraception methods such as the pills, injections or hormone releasing-Intra Uterine Devices (IUDs).

However, the overall absolute increased risk in breast cancers diagnosed among current and recent users of any hormonal contraceptive was 13%, approximately 1 extra breast cancer for every 7690 women using hormonal contraception for 1 year.

Although these findings sound scary, on the other hand, the risk is somehow similar to the breast cancer risk contributed by physical inactivity, excessive weight gain, or alcohol consumption. However, all these extra contributing factors for breast cancer risk were not excluded in this study.

In contrary, oral contraceptives use, prevents more cancers than it causes. For example, it is known to reduce the risk of ovarian cancer, endometrial cancer and there is a strong suggestion that they may also reduce the risk of colorectal cancer.

In my opinion, this should be weighed against the clear benefits of hormonal contraception use that go beyond the obvious advantages of preventing unwanted pregnancies. In addition, the search for new hormonal contraceptives that do not elevate breast cancer risk or use of copper IUDs should be alternatively emphasized.

Source:  Mørch et al. (2017).

My Cancer Research Journey as a Story

By Ramadhani Chambuso

In clinical medicine, researchers believe that HIV/HPV co-infected women progress relatively rapidly to invasive cervical cancer.

But then, I thought that may be too general because others do not progress to the invasive disease regardless of their CD4 T cell counts or Anti-Retroviral drug use.

Therefore, what I did, was to find out if host immunity and molecular genetic variations with HIV/HPV co-infection may influence early cervical cancer development. Interestingly, I have discovered that specific immune genes in combination with HIV/HPV co-infection may influence cervical cancer development in South African Women.

Conclusively, these results enlighten our insight to the disease development, add new knowledge to the existing theories in Clinical Oncology and may change the screening and management of the disease to focus or target more on individualized molecular genetic variations for cervical carcinogenesis.

Advances in our Understanding of Paediatric Brain Tumours

By Marc Hendricks

Massive advances have been made in the last forty years in paediatric oncology. The best example of this is in acute lymphoblastic leukaemia (ALL) which is the most frequently diagnosed malignancy in children and which in the early 1970s was almost uniformly fatal. Today in developed nations the overall survival for ALL tops 80%, in some countries as high as 90%. Almost every other solid paediatric tumour has followed suit except for paediatric brain tumours, which despite comprising a third of all tumours seen by paediatric oncologists, was the group in which arguably there was the slowest progress by comparison.

Recently however, the advent of molecular mapping of paediatric brain tumours has transformed the landscape of our conventional ideas of risk stratifying children with brain tumours which traditionally was built on the prospect of resectability of the primary tumour, the presence or absence of metastatic disease and the histology of the tumour.

The two most recent examples which best demonstrate this seismic shift in our understanding of paediatric brain tumours is undoubtedly the new molecular risk stratification groups which have emerged in paediatric medulloblastoma (Kool et al., 2012; Taylor et al., 2012) and the removal of the term primitive neuroectodermal tumour (PNET) from the WHO classification, following emerging studies from Sturm et al. (2016) revealing multiple molecular sub-types amongst tumours traditionally described as PNETs. Using DNA methylation profiling, the investigators were able to demonstrate amongst other things four distinct new categories of tumour each with its own recurring genetic alterations, histopathological signature and clinical characteristics.

This technology is unravelling almost faster than therapeutic interventions can keep up as new risk groups and sub-groups are identified through cutting edge laboratory work. International clinical trial groups have been quick to follow on the heels of these discoveries by incorporating molecular categorisation into new treatment protocols in order to learn more about the optimal management of these tumours. In addition, similar technologies are now being used in other groups of brain tumours with the hope that more can be learned particularly about tumours, which up to now have eluded clinicians, surgeons and radiation oncologists. This, in concert with advances in surgical and radiotherapeutic techniques, brings with it renewed hope that a new era in paediatric brain tumour management has dawned.

Source links: Kool et al. (2012), Taylor et al. (2012), Sturm et al. (2016).

del 16 in Acute Myeloid Leukaemia (AML) in children: Are the Clinical Implications for Management the Same as for Other Good Risk Cytogenetic Myeloid Leukaemias in Children?

By Marc Hendricks

Recently del 16 has been described in AML in children and adults. According to current guidelines risk stratification for paediatric myeloid leukaemias is based on cytogenetic profiling. Patients with leukaemia with good risk cytogenetic profiles are treated with intensive chemotherapy alone and are not considered candidates for transplantation in first remission. These karyotypes include t(8;21), inv(16), t(16;16) previously described in the association with historical French-American-British M4Eo and t(15;17) in acute promyelocytic leukaemia (APL) along with the other known microvariants.

With the description of the del 16 questions have been raised about whether or not this specific genetic abnormality constitutes a newly discovered good risk variant and whether the same treatment algorithm can be followed as for the other favourable cytogenetic group. The distinction is an important one because it speaks to the need for transplantation to consolidate a remission following intensive chemotherapy: in other words, can transplant be avoided or should children with del16 rather be assigned to a standard risk group and should practitioners then be looking for HLA identical donors to proceed to transplant?

Considering the small number of reported cases there is, as yet, no clear indication that the deletion is interchangeable (as it refers to risk) with inv16 and t(16;16). The source links provided highlight the recent descriptions and the controversial question that it has raised for the management of myeloid leukaemia in children.

Source links: Arthur and Bloomfield (1983),  Rogers et al. (2017), Silva et al. (2004).

HPV Testing Alone is Better than Co-testing with Pap Smear for Cervical Cancer Screening

By Ramadhani Chambuso

Despite huge research into HPV and the introduction of preventive HPV vaccines, cervical cancer screening will remain important and comprise many millions of tests annually for decades to come.

Screening by HPV testing, which detects a cervicovaginal specimen for the presence of the nucleic acids of carcinogenic types of HPV, is more sensitive than the Pap test which is a microscopic examination of exfoliated cervical cells, for detection of cervical pre-cancers, a new study in the Journal of the National Cancer Institute finds.

However, the reports of rare HPV-negative, Pap-test positive cancers are motivating the continued use of both tests (co-testing) despite increased testing costs. In addition, the HPV test captures the known cancer causing viruses only, but it is believed that there may be other unknown cancer causing viruses and so continue to do the Pap smear plus the HPV testing is crucial.

Thus, if a single screening method were chosen to complement HPV vaccination, primary HPV testing likely would gradually supplant the Pap test.

Source link: Schiffman et al. (2017).

Simplified Test for Bowel Cancer Launched

By BBC Tayside and Central Scotland

Shared by Ramadhani Chambuso

A simplified screening test to detect the symptoms of bowel cancer has been launched in Scotland following a successful pilot.

The new test only requires collecting one stool sample compared to the six separate samples previously required.

The test will be offered every two years to all men and women in Scotland aged between 50 and 74.

It is hoped the easier process will encourage more people to participate in the screening test.

Bowel cancer is the third most commonly diagnosed cancer in both men and women in Scotland.

About 3,700 new cases were diagnosed in 2015, with 95% of cases occurring in the over-50s.

The UK National Screening Committee recommended that the test is rolled out nationally after a pilot involving 40,000 people.

‘Save your life’

Phyllis Weir from Lanark was diagnosed with bowel cancer in 2013 after taking the screening test.

She told BBC Scotland: “I was shocked at the fact I had bowel cancer because I had absolutely no symptoms at all.

“I would urge people to take this test because it can save your life.

“I wouldn’t be here today if I hadn’t taken the test.

“I have spoken to so many people since then who would still have their tests sitting in their bedroom drawer if they hadn’t heard my story.”

Visiting the Scottish bowel screening lab in Dundee’s Ninewells Hospital, Health Secretary Shona Robison said: “Early diagnosis is crucial to saving lives.

“More than 90% of bowel cancer cases can be treated successfully, if diagnosed early.

“The new test is easier to use than the previous process and this will increase the number of people completing screening.

“This will enable us to detect more conditions at an earlier stage, helping more people to beat bowel cancer than ever before.”

Source link: BBC Tayside and Central Scotland.

Hepatitis B Virus Vaccination is Protective against Lymphoma Development, a Study Finds

By Ramadhani Chambuso

Hepatitis B virus (HBV) infection has been documented as a risk factor for a certain type of blood cancer called non-Hodgkin lymphoma (NHL), worldwide.

Recently, a large cohort epidemiological study involved a database of one million people for sixteen years, reports that HBV vaccination is protective against lymphoma development in the teenagers in an endemic area in Taiwan, however they suggested longer follow-up is required for older age individuals.

Furthermore, they found that HBV infection increased the risk for developing NHL and specific aggressive lymphoma, with Hazard Ratios of 4.14 and 5.52, with a higher incidence of 17.07 and 13.9 per 100 000 person-years, respectively, compared to the non-HBV cohort.

Interestingly, this study demonstrates, for the first time, universal HBV vaccination reduces the incidence of NHL in adolescent and young adults less than 20 years. Further, it suggests that cancer prevention through HBV vaccination is not only for hepatocellular carcinoma but also NHL in endemic areas of HBV infection.

To conclude, this evidence suggests that HBV could be an etiologic factor for NHL and CD20⁺aggressive lymphomas, although confirmation of the mechanism needs further studies.

Source link: Huang et al. (2017).

Cervical Cancer Screening Should be Individualized for Women Vaccinated Against High-Risk HPV

By Ramadhani Chambuso

Appropriate cervical cancer screening intervals for women vaccinated against high-risk HPV are yet to be well established and an updated screening algorithm has not been agreed worldwide.

However, a recent simulation study done in England found that the necessary number of lifetime screens for HPV16/18-vaccinated women and HPV16/18/31/33/45/52/ 58-vaccinated women were three for cervical cancer prevention in HPV16/18-vaccinated women, while just two for HPV16/18/31/33/45/52/58-vaccinated women.

Furthermore, these researchers used a microsimulation model calibrated to real published data to determine the appropriate screening intensity for vaccinated women. As well the natural histories in the absence of vaccination were simulated for 300,000 women using 10,000 sets of transition probabilities.

In addition, the linkage of vaccination status to the screening programme was done, a process already recommended earlier in England. For example, the current US guidelines recommend the same screening intervals for women regardless of vaccination status, though this is likely to be updated once vaccinated women enter screening and the data have been evaluated. Assuming future cervical screening guidelines differ for vaccinated and unvaccinated women, countries which do not have a good record of who received the HPV vaccine may wish to consider the potential use of HPV antibody testing as part of a future cervical screening programme.

Therefore, these results clearly demonstrate that the cervical cancer screening programme should be personalised based on HPV vaccination status.

Source link: Landy et al. (2017).