Head and Neck cancer-2- causes, prevention
HEAD & NECK CANCER PART-2
(All the articles published in past are available at www.shyamhemoncclinic.com/blog/)
Question: Dr. Chiragbhai, thank you for explaining in detail about major risk factors. We all knew about tobacco but it was eye opening to know about this addition of other chemicals in gutkha and pan masala creating even higher risk, and requiring much shorter exposure to cause cancer or other problems like Oral Submucous Fibrosis. And that areca nut (supari) also can cause cancer, role of hygiene, nutrition and other points were new for us. Most frightening was the number of children who are now at risk. You also mentioned about role of virus – HPV. What is that?
Ans: Yes. We are looking at a much larger burden of this cancer in next few years. If government does not take effective steps to curb use of these products, Swine flu will seem nothing compared to deaths we are facing from these cancers.
HPV – Human Papilloma Virus, is a well known cause of cervix cancer. Now it has been linked with oral cancers as well, primarily tonsil, especially in patients who are not using tobacco or alcohol. It is associated with high risk sexual behavior in many cases, but not all. These tumors also have a different clinical profile, with many of them being basaloid or poorly differentiated squamous cell, often with unknown primary and a large neck node. They respond better to chemotherapy and radiation compared to HPV negative cases, and have a better overall survival.
While we are talking about non tobacco etiology, it is important to mention EBV – Epstein Barr Virus as well. This virus is linked with nasopharyngeal and paranasal sinus cancers. This type of tumor is endemic in northern Africa and southern China, much less common in India.
Que: There is so much research ongoing, don’t we have a way to prevent or screen for these cancers, similar to cervix cancer where we have a vaccine and tests like PAP smear.
Ans: In a way it is very easily preventable i.e. avoiding tobacco products areca nut and alcohol, good oral hygiene, good nutrition. However, there are no medicines or other means to reduce risk in patients who are using these products. There have been clinical trials using antioxidants and other preventive agents, however none has shown adequate results. Also, it is very difficult to quit tobacco once addicted. Long term success rate is only about 30%. But it is still worth attempting, even if one can reduce amount of tobacco used, if not quit completely, it still reduces risk. It is extremely important to focus on measures to avoid any one starting new tobacco use. Children and young adults are the main groups at risk of starting tobacco use due to various reasons.
There are no good screening tests either. At the most, six monthly examination by an ENT or dental expert and personal awareness may pick up early lesions. Leukoplakia is the commonest precancerous lesion in oral mucosa. These appear as white plaques, and need biopsy, as some of them already harbor malignancy. Erythroplakia – red plaques – less common, but at higher risk of conversion to malignancy.
Established cancer signs for early diagnosis are: a non healing ulcer (over 4 weeks), bleeding from mouth or nose or in cough, persistent change of voice or hoarseness of voice, difficulty swallowing, pain on swallowing, enlarged neck nodes, ear pain.
Since most of these early symptoms are not severe, not painful and do not disturb regular life, patients and doctors both tend to ignore or keep treating symptomatically. These signs, especially in a patient with risk factors, must be evaluated urgently for early diagnosis. First negative biopsy in a suspicious lesion needs second biopsy and sometimes more evaluation before concluding it is benign. Most of these lesions cannot be clinically confused with benign lesions, hence it is important to pursue diagnosis rather than accept a negative report as confirmatory. Additional tests done for staging are CT scan, for some lesions MRI in addition to CT scan or by itself, a PET-CT scan in some cases. One very important part of initial evaluation in some cases is EUA – examination under anesthesia. This is done by the cancer surgeon, to establish true extent of disease. Many lesions cannot be evaluated properly without complete relaxation of patient, and modern scans also may not be sufficient. Need for this evaluation is however reducing due to modern scans.
February 12th 2015.
Dr. Chirag A. Shah; M.D. Oncology/Hematology (USA), 079 26754001.
Diplomate American Board of Oncology and Hematology.
Shyam Hem-Onc Clinic. 402 Galaxy, Near Shivranjani, Opp Jhansi ki Rani BRTS, Ahmedabad.