Lung cancer is divided into four stages (I – IV). Stage IV lung cancer is the most advanced form of the disease. This stage is characterized by the spread of the disease has to other parts/organs of the body. The tumor can spread to within and out of chest cavity, to bones, brain or any other distant organ in the body. Stage IV is also known as metastatic lung cancer. Distant deposits of the tumor are said to metastatic deposits or metastases or even secondary tumors/deposits. Therefore, stage IV lung cancer signifies an extensive, widespread cancer. No single modality of treatment is able to treat the cancer. Moreover, the curative intent of treatment is most probably replaced by palliative intent.
Stage IV lung cancer symptoms
The symptoms depend upon the organ specific involvement by the tumor. For instance:
- Bone pain or fractures in case the tumor has metastasized to bones
- Jaundice and upper GI symptoms if spread to liver
- If the cancer has spread to the brain, it may cause headaches, vision issues, difficulty speaking or seizures.
Other symptoms of stage IV lung cancer include:
- Lumps in the neck or around the collarbone
- Abdominal or back pain
- Loss of appetite
- Numbness or tingling
Types of stage IV lung cancer
There are two main types of lung cancer:
- Small cell lung cancer (SCLC)
- Non-small cell lung cancer (NSCLC)
As their names suggests, these types of lung cancer are diagnosed when a pathologist identifies a specific type of diseased cell. Diagnosis of the sub-type of lung cancer is the first step towards management of the disease.
Small cell lung cancer
About 10 percent of all lung cancers are small cell lung cancers. SCLC is an aggressive type of malignancy and spreads very quickly. There are two main subtypes of small cell lung cancer:
- Small cell carcinoma (oat-cell cancer)
- Combined small cell carcinoma
Non-small cell lung cancer
NSCLC is the commoner type of lung cancer, comprising almost 85-90% of the total number of cases. Small cell lung cancer is much more aggressive than NSCLC generally as described by lung cancer specialist in Delhi. Three main sub-types of NSCLC:
- Adenocarcinoma of the lung
- Squamous cell lung cancer
- Large-cell undifferentiated carcinoma
Treatments of stage IV lung cancer
Management protocols for stage IV lung cancer depends upon where and how extensively the cancer has spread. Also, more important is physical fitness of patient to undergo treatment with minimal risk. In most of the cases, treatment is with palliative intent, offered to ease side effects and improve quality of life. Treatment for lung cancer stage 4 in Delhi options include:
Chemotherapy form the backbone of theses subsets of patients. It might be combined with another modality to increase the effectiveness of the treatment. Chemotherapy may not be an appropriate option to treat lung cancer metastases in the brain.
Radiotherapy is used to shrink tumors, particularly useful in bone metastasis.
These are drugs which help person’s own immune system to recognize and destroy cancercells more effectively. These can be used alone or in combination for the treatment.
Rarely surgery is of use for curative intent in this stage of lung cancer. Surgical excision of tumor is not undertaken if tumor already spread to other organs (except adrenals). Surgery is used in some cases for palliation. Talc pleurodesis is one example, wherein surgery (VATS) is used to palliate malignant pleural effusion.
Targeted drugs like Bevacizumab are designed to target specific receptors(VEGF inhibitor) or proteins on cancer cells to slow tumor growth.
Another palliative treatment modality using light & light-sensitive agents to shrink tumors.
Lung cancer and life expectancy
Lung cancer in early stages have a better outlook, as the tumor is confined to the lung itself. Once the cancer breaches the domain of the lung, and spread to lymph nodes or bloodstream, it is the potential step towards metastasis. Thereafter it can spread to any part of the body.
Overall physical fitness is an important factor determining the response to treatment. For example, only a fit person can undergo pneumectomy (removal of one lung) if required for cancer. Even after so much of progress in diagnosis of lung cancer, still the majority of cases diagnosed are in late stages.
Survival rates gives us an idea of stage wise life expectancy. Though every patient needs an individualized treatment, tailored for his stage, fitness and tumor histology/markers. Needless to say there are significant individual differences.
Current survival statistics don’t tell the whole story. In recent years, new treatments/drugs have been approved for stage 4 non-small cell lung cancer (NSCLC). In many a cases NSCLC is behaving like a more aggressive chronic condition. In a way the survival rates even in stage IV have gone up significantly.
The following are the estimated five-year survival rates for NSCLC by SEER stage:
- Localized: 60 percent
- Regional: 33 percent
- Distant: 6 percent
- All SEER stages: 23 percent
Small-cell lung cancer (SCLC) is a the most aggressive form of lung cancer. For limited stage SCLC, the five-year survival rate is approx. 15%. Median survival for limited and extensive disease is 16-24 and 6-12 months respectively on treatment. The outlook without treatment is quite dismal, only 2-4 months. Long term disease-free survival is rare.
The relative five-year survival rate for mesothelioma, a type of cancer caused by asbestos exposure, is 5 to 10 percent. Look for lung cancer treatment in Delhi and recommend to those who are in need.