Understanding head and neck cancer

More than 600 new cases of head and neck cancer are diagnosed each year in Ireland


Receiving a cancer diagnosis is a daunting experience for anyone. It has an impact not only on the patient, but on their family and friends. Following a diagnosis a patient may feel a deep sense of anxiety and fear of what lies ahead. The first priority for the doctor is to give the patient a clear understanding of their disease and to outline the available treatments.

Like any great science, medicine depends on the delivery and dissemination of knowledge to drive progress, which can be interpreted in many ways. We have seen progress in the context of cancer biology and therapeutics but the dissemination of knowledge and cancer awareness to the greater public is often left lacking. Awareness potentially saves lives.

This year we mark next Monday, July 27th, as “World Head and Neck Cancer Day”. Ireland joins the international movement of 53 countries to increase awareness, and promote education and training in the diagnosis, treatment, outcomes, and research of head and neck cancer.

More than 54,000 new cases of head and neck cancer were projected in the US in 2014. In Ireland this figure is in excess of 600 new cases per year.

READ MORE

Causes

The head and neck region is an anatomically diverse region of the body that is composed of soft tissue, bones, skin, and a variety of glands and organs. Cancer is not one disease but many diseases and is ultimately caused by the uncontrolled growth of a single cell.

There are many different types of cancer within the head and neck, each with their own tissue characteristics and biological behaviour.

Cancers may develop in several areas of this region, including the mouth, throat, larynx (voice box), glandular tissue (thyroid), salivary tissue (parotid gland), lymphatic tissue, nose and sinuses.

Head and neck cancers form after an accumulation of genetic events, which are accelerated by genomic instability related to carcinogen, or cancer-causing exposures, particularly tobacco and alcohol.

The link between cancer and cigarette smoking is now indisputable. Both alone and in synergy with alcohol, smoking is the consistent finding within the social history of the majority of our patients. Tobacco use and alcohol consumption account for an estimated 74 per cent of cancers of the head and neck.

Smoking

On a cellular level, tobacco exposure is associated with increased rates of p53 mutations. This p53 is a protein which acts as a tumour suppressor that accumulates in response to cellular stress, including damage to the genome or DNA of the cell. Accumulation of p53 induces an arrest in the cell cycle of growth.

This allows the cell to repair the segment of damaged DNA and then continue with normal cellular function. If damage is beyond repair, p53 causes the cell to die. Mutations in p53 have been associated with decreased overall survival and increased recurrence of disease because of decreased therapeutic response.

All our patients are encouraged to stop smoking, with the assistance of our smoking-cessation officer.

Unfortunately, such is the power of addiction that the majority fail to give up smoking, even after their diagnosis.

There are many forms of nicotine- replacement therapies including patches, nasal sprays, gums, inhalers and lozenges. In recent times, electronic cigarettes – or ecigarettes – have become widely available. The main issue of contention is the lack of regulation surrounding certain constituents and the product design. Safety issues arise from potentially defective battery-powered heating elements, leaking nicotine cartridges, and nicotine poisoning in young children.

HPV

Human papilloma virus (HPV) is a well-documented carcinogenic risk factor in the context of cervical cancer. Although there are more than 100 types of HPV, only a small number of these are considered high risk or carcinogenic.

One type, HPV16, is responsible for the majority (more than 90 per cent) of HPV head and neck cancers. HPV causes a distinct subset of HPV-positive head and neck cancers that arise in the lymphoid tissues of the palatine and lingual tonsils.

These tonsillar structures are within an anatomical subsite of the head and neck called the “oropharynx”. Patients with a HPV-driven oropharyngeal cancer are predominantly male, within the 50-60 year- old age group and often without a smoking history.

HPV is a sexually transmitted infection. Although it is difficult to delineate which specific behaviours confer the greatest risk of oral HPV infection and HPV head and neck cancers, oral sexual behaviours are believed to be the primary mode of transmission.

The proportion of oropharyngeal cancers attributable to HPV in the US rose from 16 per cent in the 1980s to almost 80 per cent in the past decade. We are seeing a similar pattern emerge in Ireland.

HPV-positive tumours are significantly more responsive to therapy than HPV-negative cancers because there are fewer mutations present within the viral carcinogenic cancers compared with the classical chemical carcinogenic (smoker/drinker) tumours. Therefore, having a HPV-positive tumour brings with it a survival advantage compared with classical cancers in this region.

Despite the overwhelming evidence supporting the role of HPV in the etiology of oropharyngeal cancer, it has not been conclusively linked to other cancers, namely oral cancer or larynx cancer.

HPV vaccination

In Ireland, we have an excellent HPV-vaccination programme to reduce the risk of cervical cancer for girls. Vaccination is most effective in childhood or early adolescence, prior to the initiation of sexual activity and exposure to HPV. Vaccination against HPV can be administered in two forms. HPV 16 and 18 are the vaccine types for the bivalent vaccine, and HPV 6, 11, 16 and 18 are the vaccine types for the quadrivalent vaccine.

By the end of 2013, more than 144 million doses of the quadrivalent vaccine and about 41 million doses of the bivalent vaccine had been distributed worldwide. WHO’s Global Advisory Committee on Vaccine Safety has reviewed safety data for both vaccine types on a number of occasions, most recently in March 2014.

These reviews continue to affirm HPV vaccines as highly immunogenic, safe and effective.

The incidence of HPV-positive head and neck cancer is now expected to exceed cervical cancer incidence in the US by 2020 and, therefore, the role of vaccination is essential.

It is imperative that we now introduce a vaccination programme for Irish boys as some of our international counterparts have done to protect both girls and boys against the oncogenic dangers of this virus, both in the cervix and the oropharynx.

Investigating a patient with suspected head and neck cancer Initial clinical consultations of our patients involve a thorough history and detailed examination in an effort to define the clinical problem. Patients with cancers of the head and neck have a large variety of symptoms and signs according to the subsite of the disease.

These may include shortness of breath, hoarseness, difficult or painful swallowing, weight loss, a non-healing ulcer in the mouth, loose teeth, neck lumps, persistent ear pain, spitting or coughing blood.

Once a diagnosis is established, treatment is decided according to the stage of disease, stage 1 indicating early disease and stage 4 being advanced. The same staging system is employed worldwide and this allows for standardisation of cancer care and clinical research specific to each cancer subtype.

Decision-making in the treatment of any head and neck cancer patient is made with input of the multidisciplinary team (MDT).

The MDT includes ear, nose and throat (ENT) specialists, head and neck surgeons, radiation oncologists, maxillofacial surgeons and allied dental experts, neuro-radiologists, pathologists, medical oncologists, physiotherapists, speech and language therapists, nutritionists and oncology nursing specialists.

Successful treatment of patients with head and neck cancer is predicated on MDT strategies to maximise oncologic control and minimise the impact of therapy on a person’s form and function.

Contemporary oncology follows “evidence-based medicine”; in other words, statistically proven therapeutic modalities published in peer-reviewed journals. Anything beyond that is simply reckless and dangerous.

Occasionally we see patients deciding to substitute alternative therapeutic approaches for conventional, sometimes at considerable cost to themselves and their family.

In my experience this has always resulted in a frustrating delay in effective therapy. Alternative medicine as a substitute for conventional therapy has absolutely no role in attempting to cure head and neck cancer.

I would, however, fully support alternative or complementary techniques when applied as part of an integrative medical strategy. In Memorial Sloan Kettering Cancer Center in New York, where I received my fellowship training, certain patients receive a variety of services to complement traditional medical care; these include acupuncture, music therapy, mind/body therapies, dance and movement therapy, yoga, and touch/massage therapy. I believe these had a positive impact on the patients and their families during intensely stressful times.

Cancer therapy The head and neck have essential functional roles including talking, breathing, smell, vision, hearing, chewing, swallowing and our aesthetic appearance. Therefore, any therapeutic intervention carries significant potential morbidity. We treat cancer with three main modalities: surgery, radiation therapy or chemotherapy.

Surgery of the head and neck incorporates many different techniques and skills. We are now in the age of highly specialised technological innovations. There is a drive towards minimally invasive surgery. These techniques include endoscopic surgery with high-definition telescopes, laser systems with microscopic accuracy, and robotic surgery.

They have the potential advantage of improved rehabilitation, less pain and reduced post-operative stays in hospital. Robotic surgery has taken off internationally but there is not a single robot in the public healthcare system in Ireland.

In recent years, radiation oncology has also made significant advances in its therapeutic application, especially with the use of conformal techniques (IMRT), which shape the radiation beam to closely approximate the shape of the tumour. This reduces the potential side effects and allows a higher radiation dose to be applied directly to the tumour.

Overall, some head and neck cancers have an excellent prognosis. Unfortunately, two-thirds of all our patients present with advanced disease at the time of diagnosis. If these patients fail our first line of therapy, their prognosis is often very challenging.

Head and neck cancers often advance quickly and, given the anatomical complexity of the region, frequently impinge or invade the patient’s airway. This highlights the need for effective and efficient therapy for all these patients.

The reality of the Irish healthcare system is one of bed closures, theatre closures, staffing shortages, consultancy vacancies, overcrowding and a fundamental lack of resources. Irish oncology patients face these additional challenges that are unrelated to their disease but play a direct, unacceptable and unwanted role.

We can and should be able to do better in modern Ireland.

James Paul O'Neill is professor of otolaryngology, head and neck surgery at the Royal College of Surgeons in Ireland and Beaumont Hospital, Dublin. See your doctor if you have any of these symptoms A sore in the mouth that won't heal (the most common symptom) or that bleeds easily. A red or white patch in the mouth that won't go away. Difficulty chewing, swallowing, or moving the jaws or tongue. Numbness in the tongue or other areas. Loosening of teeth or dentures that no longer fit. A lump or swelling in the neck. Frequent nosebleeds, ongoing nasal congestion, or chronic sinus infections that do not respond to treatment. Persistent sore throat. Persistent hoarseness or a change in the voice. Persistent pain in the neck, throat or ears. Blood in the sputum. Changes or discolouration in a mole; a skin sore that is crusting or ulcerated, or that fails to heal (these are also signs of skin cancer).

World Head and Neck Cancer Day Next Monday, all across Ireland, specialists will be promoting awareness of and education in the diagnosis and treatment of head and neck cancer.

Royal College of Surgeons in Ireland (Albert Theatre), Monday, July 27th, 6.30pm to 9pm: Head and Neck Cancer Symposium. Some of Ireland's top oncology doctors and surgeons will give free public lectures and reception.

Free head and neck screening clinics, 1-2pm, Beaumont Hospital, ENT Outpatients, ground floor.

St Vincent's University Hospital, Elm Park, Department of ENT, first floor. University Hospital Galway, ENT Outpatients Clinic. University Hospital Waterford (UHW), ENT Outpatients Clinic.

UHW 9.30am – Opening address by Lord Mayor of Waterford.

UHW 9.45am – Irish Cancer Society information session

Sligo General Hospital, The Mall, ENT Outpatients Clinic.

University Hospital Limerick, Dooradoyle, Mid-Western Radiation Oncology Centre 12.30-13.30pm.

Educational head & neck cancer evening, 7pm-8.15 pm,

The Golf Clubhouse, Adare Manor Hotel & Resort, Adare, Co Limerick.

South Infirmary Victoria University Hospital, Cork:

Opening of flexible CO2 laser system and public lectures in the Department of ENT. Contact the department for confirmation of date and times.