HEAD & NECK CANCER PART-10
(All the articles published in past are available at www.shyamhemoncclinic.com/blog/)
Question: Thank you Chiragbhai for explaining role of chemotherapy in last part, especially combined chemotherapy and radiotherapy, and how it has replaced surgery for cancers of larynx, hypopharynx, tonsil, base of tongue, nasopharynx and few other sites.
You mentioned that chemotherapy gives about 80% response rate in these cancers. What is the role of chemotherapy other than with radiotherapy, as primary curative modality?
Ans: Chemotherapy is also used after surgery (Adjuvant), to reduce chances of relapse. In some high risk cases, chemotherapy is given after surgery, in combination with radiotherapy. Main features that predict need for addition of chemotherapy in this setting are: either one or both of the two features:
1. Extracapsular nodal spread
2. Positive surgical margins
Other high risk features, which merit consideration for addition of chemotherapy to radiotherapy are as noted below. They are not considered mandatory due to improvement in progression free but not overall survival: multiple nodes (without extracapsular spread), lymphatic or vascular or perineural invasion, T3 or T4 tumor, oral cavity or oropharyngeal primary with positive level 4 or 5 nodes. These are established risk factors for addition of radiotherapy alone.
Induction chemotherapy has been studied extensively prior to radiotherapy. Goal is to reduce tumor size and early studies showed improvement in overall survival. However, this is not a standard of care, and large studies are ongoing to compare Combined chemoradiation Versus Chemotherapy followed by radiation. As of now, most patients should receive combined chemoradiation (preferred agent is 3 weekly high dose cisplatin). Some patients who are not fit enough to start with combined chemoradiation due to mainly nutritional issues, may be considered for chemotherapy first to improve their weight and nutritional status or for elderly people with fitness concerns. This can be followed by either radiation alone or radiation combined with single agent carboplatin or cetuximab.
It must be noted however that a large number of patients in India are not able to tolerate standard 3 weekly high dose cisplatin combined with radiotherapy. A number of patients come with significant weight loss already and other nutritional impairments such as vitamins and protein deficiency. These patients benefit from alternate approaches like induction chemotherapy or combining radiation with easier options like carboplatin or weekly cisplatin.
Chemotherapy is NOT recommended in general for converting inoperable patients to operable. Preoperative chemotherapy is NOT standard, and should be used very selectively, if at all. This may come as a big surprise to many clinicians but is the fact.
Que: What are the other uses of chemotherapy?
Ans: One very important role is in curative treatment of nasopharyngeal cancers. Once again it is combined chemoradiation, using cisplatin. But in addition, there is important role of only chemotherapy after surgery for 3 cycles, using cisplatin and 5-FU. This is different from other sites, where only chemotherapy has no role.
A new, fast developing role is combining chemotherapy with reirradiation. Few patients may achieve long term survival with this approach. As we have seen during radiotherapy articles, repeat radiotherapy is now feasible in a select subset of patients, especially if they received radiotherapy using modern techniques like IMRT during their initial radiotherapy treatment.
Of course, chemotherapy has important role in palliation of many patients who are inoperable or have relapsed with inoperable or metastatic disease. It is important to note that single agent chemotherapy should be used in palliative setting in most cases. Combination chemotherapy is more toxic and does not result in better survival. Cetuximab and gefitinib are also used in palliative setting, with or without chemotherapy. For patients with poor performance status, chemotherapy should be avoided. Similarly, patients who have not responded to chemotherapy or have shown minimal response, should be considered for supportive care only. A number of patients cannot be given chemotherapy also because of lack of fitness, due to inability to eat from locoregional issues (such as orocutaneous fistula) or significant weight loss. Good palliative care referral is the best option for these patients, rather than subjecting them to side effects of chemotherapy.
October 14th 2015.
Dr. Chirag A. Shah; M.D. Oncology/Hematology (USA), 079 26754001. Diplomate American Board of Oncology and Hematology. Ahmedabad. firstname.lastname@example.org Shyam Hem-Onc Clinic. 402 Galaxy, Near Shivranjani, Opp Jhansi ki Rani BRTS, Ahmedabad. www.shyamhemoncclinic.com