Data from the Department of Health reveals that Lung Cancer is the second most common type of Cancer among Hong Kong residents (behind Colorectal Cancer). But while slightly more patients get diagnosed every year with Colorectal Cancer, Lung Cancer is the most deadly Cancer for the local population, accounting for 28.2% of all Cancer deaths in 2015.
There are different types of primary Lung Cancer and they are divided into 2 subtypes:
- Small Cell Lung Cancer (SCLC), which accounts for 15% of new cases, and unfortunately has very few treatments that have shown effectiveness in its treatment.
- Non Small Cell Lung Cancer (NSCLC), which includes several further subtypes, accounts for 85% of all new Lung Cancer cases, and has had several meaningful breakthroughs in its treatment over the last few years, which have improved the outcomes for patients suffering from variants of this disease.
Both types are attributable to genetic mutations, with smoking being a major risk factor for the development of both types. Interestingly enough, some research done recently has shown that Asian patients actually respond better to some of the newer treatments for Lung Cancer than patients from a European descent.
Lung Cancer is discovered in most patients after the disease has progressed to an advanced stage, and respiratory symptoms have appeared. Many diagnostic tests are then utilized in the diagnosis and staging of Lung Cancer:
1. Computed Tomography (CT) of the chest is the most commonly used imaging modality for determining the existence and spread of Lung Cancer. In some countries, low dose CT scans are used for screening of patients who are at increased risk for Lung Cancer.
2. Brain imaging using Magnetic Resonance Imaging (MRI) is very useful for detection of brain metastasis, which is quite common and very dangerous for patients suffering from Lung Cancer.
3. Nuclear imaging (PETCT) is also very useful for examining the patient’s entire body for distant metastasis.
4. Pathology and molecular testing of tumor samples are crucial for deciding regarding on the best treatment approach for patients with advanced disease. Samples from the tumor are usually taken using Needle Biopsy, Bronchoscopy or Thoracoscopy.
For patients with localised disease, surgery and/or Radiation Therapy have been the most proven treatments for a long time. For patients with advanced disease which has spread outside the lung, treatment with Chemotherapy can be beneficial, but has been very unsatisfactory, as far as disease outcomes go, for many years. Given the deadly nature of this disease, many new treatments have been developed over the last few years.
For 35% of East-Asian patients who suffer from NSCLC, the disease is related to a somatic mutation of the EGFR gene. This mutation helps the Cancer cells grow and proliferate. However, this mutation has also been used as a weapon against the Cancer, by researchers who discovered that treatments that target it can be very effective, when this mutation is discovered by biopsy and molecular testing.
Such treatments include 1st generation TKIs like Erlotinib and Gefitinib. When it was seen that these Cancers can mutate themselves in order to develop tolerance to the 1st generation treatment, further 2nd generation (Afatinib) and 3rd generation (Osimertinib) treatments were developed, which can be used in some cases when the 1st generation inhibitors stop being effective. Results from clinical trials with Osimertinib appear to indicate that it could quickly become the preferred first treatment for many options with EGFR positive disease.
Professor Mok Shu Kam, Tony, a researcher and Oncologist at the Chinese University of Hong Kong and the Prince of Wales Hospital, led one such clinical trial, which demonstrated that patients with specific EGFR mutations can have a good response to Osimertinib, even after disease progression on other treatments.
Professor Mok is considered to be one of the world's leading experts for this disease and has gained a very high global reputation; he is part of the very well regarded Oncology team at the Prince of Wales Hospital, which includes great experts in other types of Cancer as well, such as Professor Chan Tak Cheung, Anthony (an expert in Head and Neck Cancers), and Professor Winnie Yeo (an authority in Gastric Cancers).
Another meaningful advancement in the field of Lung Cancer is attributed to Professor Lam Bing, previously of the Hong Kong University, an expert in respiratory diseases, who led a clinical trial that showed the effectiveness of Sputum Cytology tests in early detection of Lung Cancer.
Immunotherapy treatments, such as PD-L1 blockade drugs (Keytruda, Opdivo), also hold great promise in the treatment of Lung Cancer. While this type of treatment made headlines last year after showing significant benefit to patients with advanced Melanoma, which previously had no effective therapeutic options, similar trials for patients with NSCLC also showed very promising results, especially for patients whose diagnostic testing for PD-L1 expression is positive.
There is more hope today for Lung Cancer patients.