Posts tagged ‘head and neck cancer’

Researchers from Princess Margaret Hospital (PMH) have identified a new enzyme that affects radiation response in patients suffering from head and neck cancer. PMH researchers have made a discovery that may be significant in controlling the side effects for cancer patients. They have discovered that targeting an enzyme called Uroporphyrinogen Decarboxylase (UROD) can sensitize diseased tissue to radiation and chemotherapy.

UROD has been identified as a key ingredient in human cancers and the study suggests that targeting UROD can selectively enhance the effects of radiotherapy and chemotherapy in cancerous tumors of head and neck while minimizing toxicity to normal tissues. These findings have been published in Science Translational Medicine.

Chief investigator, Dr. Fei-Fei Liu (Professor of Radiation Oncology at the University of Toronto and PMH, and Senior Scientist at the Ontario Cancer Institute and The Campbell Family Cancer Research Institute) states that analysis of patient biopsies disclosed that UROD levels were higher in tumor tissues than in the normal ones. UROD can be used to make a general prediction of how will a patient respond to radiation therapy since the cancer patients with lower UROD levels prior to radiation treatment had improved clinical outcome.

Dr. Emma states that lower doses of radiation and chemotherapeutic drugs could be administered to cancer patients without affecting the treatment efficacy. Dr. Liu says that UROD is an enzyme that participates in production of a molecule called heme that is vital to all body organs. Targeting UROD creates an opportunity to exploit the heme synthesis pathway that disrupts the equilibrium of iron and free radical levels in cells which thereby kills cancer cells.

Source: http://www.eurekalert.org/pub_releases/2011-01/uhn-pmh012511.php

A robotic surgical procedure, which is less intrusive, to cure the malevolent swelling in the upper airway and digestive track is as effectual as other minimally intrusive surgical procedures anchored in patient function and endurance, as per the canvassers at the University of Alabama (UAB) located at Birmingham. The squamous cell carcinomas linked to the head and neck answer for approximately 4% of the cancerous growth detected in America yearly. At present, the common minimally insidious surgery for these swellings is transoral laser microsurgery.

UAB’s otolaryngologist and this investigation’s chief author, Scott Magnuson, and his colleagues from the UAB and the Mayo Clinic analyzed 89 patients with diverse phases of squamous cell carcinomas associated with the head and neck. All of the patients were scrutinized during their stay in the sickbay and up to 33 months subsequent to surgical treatment. The general two-year endurance percentage for these patients was 86.3 percent, which is analogous to the standard healing, as per Magnuson, who is also a scientist in the UAB’s Comprehensive Cancer Center. He has mentioned, however, that the patients with swellings in the initial stage seemed to have little better endurance, bereft of cancerous repetition, than those with advanced stages.

Magnuson stated that the patients’ ability to swallow differed based on the site of the tumor, preoperative swalloing capacity, the cancerous stage and the patients’ age. These findings on function were in line with earlier investigations. Some patients endured an oral diet 48 hours subsequent to surgical procedure while some were released with a temporary nasal feeding tube or lasting gastric feeding tube. He has revealed that all the patients in the investigation repossessed the swallowing power at the moment of the ultimate follow up visit, with no patients remaining reliant on feeding tubes. Magnuson has mentioned that the study’s repercussions are positive and illustrate that robotic surgery tenders a scientifically viable and oncologically credible treatment.

Magnuson also said that this is, however, a comparatively fresh procedure, and long-standing oncological ramifications are not obtainable. Nevertheless, early functional and oncological results rationalize the continued healing of select patients, who possess squamous cell carcinomas associated with the ‘head and neck’, with computerized surgeries. Transoral robotic surgery (TORS) has been proved in former studies as one operation that diminishes overall patient morbidity and death, chiefly in the capability to ingest subsequent to surgery. TORS is at present endorsed by the Food and Drug Administration (FDA) to cure T1 and T2 oropharyngeal tumors.

Source:

http://esciencenews.com/articles/2010/12/20/robotic.surgery.head.and.neck.cancer.shows.promise

http://www.emaxhealth.com/1024/robotic-surgery-shows-promise-head-and-neck-cancer-treatment

A pioneering study from UC Davis Cancer Centre by Allen M. Chen and his fellow researchers has revealed the fact that for cancers of the head and neck, those who have never smoked have much better survival rates than smokers after the application of radiation therapy. This unique research outcome is one of its kind, probing into prognosis variations resulting from a patient’s smoking history.

According to Chen, ‘There is something unique about the biology of head and neck cancers among non-smokers that makes them more amenable to cure by radiation therapy’. He further states, ‘These tumors just melt after a few doses of radiation. If we could understand why, there would be important implications for new drugs and treatments’.

Chen brings across a few possible explanations which might enlighten cancer research and treatments. His foremost suspect for propelling this difference in radio therapy reception amongst patients is human papillomavirus (HPV), a sexually transmitted disease primarily associated with head and neck cancer of never-smoking patients.

Chen said, ‘The most common theory is that these tumors express a characteristic viral antigen on the cell surface that makes the immune system recognise the cancers more readily, which may enhance the effects of radiation’.  A further theory by Chen implies that non-smoking patients carrying HPV-related tumors have lesser number of mutations in key  genes critically responsible for radiation purposes.

To further impose his insinuations empirically, Chen compared 70 smoking patients diagnosed with non-metastatic squamous cell carcinoma of the mouth and throat from the UC Davis Department of Radiation Oncology with another 70 non-smoking patients, considering the subjects evenly on the basis of age, gender, ethnicity, stage of disease, history of treatment and primary tumor sites.  The results turned out to be immensely impressive.

Chen’s study revealed that 14 of the 70 never-smokers experienced a reappearance of the disease as compared to the 26 patients having a smoking history. Furthermore, 82 percent of the non-smokers continued to be free from the disease after a period of three years as compared to the smoker patients. Most importantly, the patients who never had a smoking history underwent minimal treatment complications than the smokers.

Chen’s analysis is proving to be a groundbreaking incident in the history of cancer research and treatment. His subsequent endeavour is to identify biological or genetic differences among smoking and never-smoking head and neck cancer patients who are undergoing radiation therapy. He announces, ‘We are in the process of conducting several laboratory experiments designed to better understand why cancers arising from never smokers are so exquisitely radiosensitive.’ This might be the answer to all queries regarding differences in prognosis.

Source: American Journal of Clinical Oncology

The outcome for cancers of the head and neck is more likely to be influenced by social behavioral patterns instead of genetic ancestry, especially in African Americans, revealed the results of a study that had been undertaken by the Henry Ford Hospital.

While the researchers uncovered evidence of self reported African Americans facing a far greater risk of developing the terminal stage of cancer, there are no hard facts available that can correlate the ancestry with cancer stage or survival.  On the contrary, evidence shows only about 5% of the persons who reported themselves of African American ancestry to have 95% or more of West African ancestry.

The study leader and director of research associated with the Department of Otolaryngology, Henry Ford Hospital, Maria J. Worsham, said that this was the first possible piece of evidence which used genetic races to find out about the various stages of cancer as well as survival rates in patients diagnosed with head and neck cancer.

While the number of African Americans being diagnosed with late stages of cancer have more chances of succumbing in comparison to the Caucasians, it has not been possible to get a consensus on the possible causes so far. However, factors like the stage of cancer at diagnosis, access to health care as well as the insurance status are all likely to contribute to the equation. Smoking and consumption of alcohol are also regarded as two principal risk factors for this particular type of cancer.

The results of the study were brought forward at the annual meeting of the ‘American Academy of Otolaryngology–Head & Neck Surgery Foundation’ at Boston on 26th September.

The actual study was conducted on 358 patients, 37 of whom were African Americans. The researchers looked at the diagnosis particularly the late stages vis-à-vis the early ones along with the overall survival rate for African Americans suffering from HNSCC or Head and Neck Squamous Cell Carcinoma. It was conducted on the basis of their self reported race which could be traced back to the West African ancestry.  The study was also based on the panel comprising of 100 AIMs for estimating the genetic background.

The ultimate result could not establish any relation between the West African ancestry and the outcome of HNSCC.  It was the only the self reported race which was associated with the various stages of the head and neck cancer.

Source: Public Release by Henry Ford Health System on 26th September, 2010.

Study co-authors:  George Divine, Ph.D., Henry Ford Biostatistics and Research Epidemiology; Rick A. Kittles, Ph.D., University of Illinois School of Public Health.