8.3 Small Cell Lung Cancer Treatment
8.3.1 Small Cell Lung Cancer Treatment Overview
8.3.3 Radiation Therapy
8.3 Small Cell Lung Cancer Treatment: (SCLC)
For patients with Small Cell Lung Cancer (SCLC), studies have shown that the outcome of treatment is, generally, not affected by the stage of the tumor. The two stages that used are, ‘limited-stage’ and ‘extensive-stage’ SCLC.
8.3.1 Overview of Small Cell Lung Cancer Treatment
The reason for the importance placed on determining the neuroendocrine origin of a lung cancer, as is the case for small cell lung cancer, is because this type of lung cancer is very responsive to chemotherapy and radiation treatment.
Small cell lung cancer is a very rapidly-growing cancer that begins to metastasize very early on in its growth. Because of this behavior, small cell lung cancer usually presents with metastatic disease; this is why treatment strategies are those of systemic (whole-body) therapy.
Studies have shown that local tumor spread occurs in up to 80 % of patients with small cell lung cancer when treated with chemotherapy alone. In addition, the combined use of thoracic radiation therapy, significantly reduces the high local recurrence rate.
Patients with limited-stage small cell lung cancer will have chemotherapy, thoracic radiation therapy and possibly prophylactic radiation treatment of the brain.
Table 8.3 Treatment of Small Cell Lung Cancer (SCLC)
For patients with limited-stage small cell lung cancer who have no distant metastases, no evidence of disease in the mediastinum and no clinical contraindications to surgery, surgical resection is indicated. Adjuvant chemotherapy, with four cycles of cisplatin-based treatment, follows the surgery.
Chemotherapy is a treatment option for both limited-stage and extensive-stage small cell lung cancer.
Firstly, for limited-stage disease, a single chemotherapeutic drug is used in combination with radiation. More commonly, a platinum-based drug (carboplatin or cisplatin) in combination with etoposide. Alternative treatment includes combination chemotherapy with four cycles of a platinum-based regimen in conjunction with thoracic radiation therapy.
For patients who have symptoms of superior vena cava (SVC) obstruction, chemotherapy is the initial treatment of choice as the response to chemotherapy is usually rapid.
In extensive-stage disease, a combination of two chemotherapeutic drugs may be necessary, the choice of which may vary.
8.3.4 Radiation Therapy
Radiation treatment is used in almost all cases of limited-stage small cell lung cancer. A single external radiation port may treat limited-stage small cell lung cancer.
Limited thoracic radiation therapy fields will include the residual post-chemotherapy tumor and all involved lymph node regions. In some cases, oncologists will use thoracic radiation therapy with the first or second cycle of chemotherapy, rather than with later cycles of chemotherapy.
In some cases, together with the first or second cycle of chemotherapy, the treating medics also give thoracic radiation therapy.
If patients with extensive-stage small cell lung cancer do not respond to chemotherapy, radiation therapy may be necessary. For extensive tumors, radiation to larger areas of the body may be necessary. Sometimes, oncologists will use thoracic radiation therapy and chemotherapy together . In other cases, radiation therapy may be necessary after the completion of chemotherapy.
Positron emission tomography (PET) may be used to image the thorax and has a role in radiation treatment planning.
Patients who have a good, partial response to their initial chemotherapy may have prophylactic cranial irradiation (PCI). Also, if there is metastasis from small cell lung cancer to the brain, PCI is sometimes the treatment of choice .
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Medline Plus Lung cancer – small cell (Retrieved 3rd May 2015): http://www.nlm.nih.gov/medlineplus/ency/article/000122.htm