With the Yahoo blog coming to the close.
I would like to write my last blog on target drug therapy for non small cell lung cancer which turn out to be unresectable.
The treatment of lung cancer always falls into a trap of discovering the tumour late.
For small tumour in young patient, the impact on breathing and systemic upset is minimal.
Only large tumour is symptomatic
But it is not necessarily that small tumour need to grow big to disseminate to other part of body.
Quite a lot of patient present with serious or widespread metastases when diagnosed lung cancer.
Today tissue biopsy is mandatory as genetic study is important to guide target drug therapy.
Usually the EGFR is tested first followed by EMLA- ALK and some time Kras study.
The latter is mainly for prognosis purpose.
Is testing for EGFR mutation and ALK-FISH testing mutually exclusive each other?
Since if EGFR is +ve, oral tyrosine kinase inhibitor is used with good efficacy.
If EGFR is -ve, traditional chemotherapy with cisplatinum + permetrexed is the norm.
With failure of response to chemotherapy, the use of monotherapy with crizotinib is considered after ALK testing,
response is usually remarkable.
The concern of cost makes crizotinib not popular. As in every new drug without competition, usually the cost or charge is arbitary.
with oral TKI, now Iressa and erotinib( Tarceva) has good and patient- benefited competition. Not long later, a new oral TKI known as Icotinib will be entering the market, this would further bring down the charges.
Also the percentage of alk FISH mutation +ve is only 6 - 8 % wihich is growing as more patient are tested routinely.
But oral TKI does not eradicate the disease.
It dose shrink the disease but in much longer duration compared to debulking surgery.
Eradication of remaining non dividing tumour cells remain either the chemotherapy drug or self immunity.
Non cessation or long term oral drug therapy with TKI is compulsory.
So after Complete remission by all radiological or chemical criteria and clinical assessment, chemotherapy may be worthwhile.
Post down-staging debulking surgery may also be considered.
Rechallange with oral TKI after stopping is also reported sometimes to be useful.
So practically all lung cancer can be successfully palliated either with oral TKI drug or iv chemotherapy. But to improve survival, early detection is much more effective.
Cessation of smoking helps but genetic factor predisposing adenocarcinoma is best fought with screening low dose CT scan of thorax.
Surgery is still the gold standard for curative treatment of lung cancer.
Dr Chung Shiu Shek Phone 3160 88 65 or HK side 3543 1814