HEAD & NECK CANCER PART-8
(All the articles published in past are available at www.shyamhemoncclinic.com/blog/)
Question: Thank you Chiragbhai for explaining very important aspects about radiotherapy. Increasing levels of complexity with 3-D, IMRT, IGRT were made quite clear. We also understood why IMRT is important for critical sites like head and neck region, prostate, cervix cancers. Also, you made it quite clear that Radiation Oncologist and his team is more important than the machine, for most indications.
As doctors we need to be sensitive about needs of our patients. It is important for us to improve our knowledge so that we can guide them better, more so in such serious disorders. Are there any other points we need to know about radiotherapy?
Ans: There are many, but we will cover only the major ones.
One more advance in this field is Rapid Arc. Rapid Arc allows much faster delivery of radiotherapy. This reduces the time required for patient to be on radiation table, thus improving patient convenience. Both of these are available in few modern radiotherapy centers.
Radiotherapy machines have been improving due to better software and hardware, primarily a function of improving computers. Thus, even among these, newer versions have few more features e.g. IMRT in latest machine will have advanced version of IMRT with some improvements. OVERALL, DO REMEMBER HOWEVER THAT MORE IMPORTANT IS THE RADIATION ONCOLOGIST AND HIS TEAM, WITH AT LEAST A REASONABLE MACHINE. They need to give plenty of time to understand patient details, to work with surgeon/medical oncologist and other team members, to give sufficient time to plan radiotherapy and ensure it is delivered properly. These are more important features to assess, rather than details of machine.
Fourth level one may say is CyberKnife, SBRT etc. These are like specific surgical instruments useful only in specific cases. Primarily they are used only in few cases of stage 4 cancers, as palliative radiotherapy. Thus their usefulness is for very limited cases, and that too is not curative. Cyberknife is like a Robot which can deliver radiation from any angle thus achieving very high conformity (not possible with modern linear acclerator). Ability to achieve such angles is important for certain sites and for repeat radiation. They can be used for stereotactic radiotherapy or radiosurgery. Apart from angle, other advantage is that extremely high doses can be delivered in 1-5 fractions – used frequently for recurrent brain tumors. This method is also used in palliative setting for lung or liver isolated metastatic spread. Added advantage here is shorter duration of radiotherapy, 1 to 5 days, rather than 2 to 4 weeks.
Que: Wonderful. So now we are much wiser about how to choose radiotherapy center for our patients. You mentioned earlier about how radiotherapy has replaced surgery in few sites. Can you elaborate?
Ans: Sure. As you can understand, cancer surgery for few body sites can be quite difficult and with serious impact on quality of life by way of loss of function or cosmesis. Examples are head and neck region, bladder etc. Fortunately for many such sites, radiotherapy and chemotherapy given together (known as concurrent chemoradiation) is as effective as surgery in curing cancer, and yet with much better safety and quality of life. Important such sites include cancers of base of tongue, tonsil, hypopharynx (pyriform sinus), larynx, nasopharynx etc. For these sites, chemoradiation is the standard of care, not surgery. First such breakthrough came in larynx cancer, where surgery led to permanent loss of voice, whereas chemoradiation could preserve that. Most commonly used chemotherapy in this situation is cisplatin or carboplatin. They are given in small doses, once every week or three weeks, as outpatient basis. For some patients where chemotherapy may not be feasible or tolerable, a non chemotherapy agent Cetuximab can be combined with radiotherapy, also giving good results.
For head and neck region, chemoradiation is also the standard of care for inoperable squamous cell cancers, and improves survival significantly, compared to only radiotherapy. It is also the standard of care for postoperative treatment of high risk cancers, such as those with positive resection margins OR extracapsular extension of nodal disease.
Chemoradiation is generally safe even when patient may be medically unfit for surgery.
Chemoradiation has also replaced surgery for few other body sites, such as cervix, esophagus, lung, bladder, anal canal etc. Clinical trials are ongoing for few other sites as well.
I AM INDEBTED TO DR VIVEK BANSAL, FOR HIS SUGGESTIONS.
August 8th 2015.
Dr. Chirag A. Shah; M.D. Oncology/Hematology (USA), 079 26754001. Diplomate American Board of Oncology and Hematology. Ahmedabad. email@example.com Shyam Hem-Onc Clinic. 402 Galaxy, Near Shivranjani, Opp Jhansi ki Rani BRTS, Ahmedabad. www.shyamhemoncclinic.com