Extensive Stage Small Cell Lung Cancer

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Small cell lung cancer is less common than non-small-cell lung cancer, accounting for about 15% of lung cancers. It tends to be more aggressive, growing rapidly and spreading quickly, but often responds well to chemotherapy. Unlike non-small cell lung cancer, the malignancy is divided into only two stages: limited and extensive.

Extensive stage small-cell lung cancer is defined as the stage during which the cancer has metastasized (spread) to other parts of the body, such as the lung or brain. The liver, adrenal glands, and bone are also common sites of metastasis.

Roughly 60 to 70% of people with small-cell lung cancer will have extensive disease at the time of diagnosis. In the past, chemotherapy was the primary treatment, with or without radiation. In 2018, however, it was found that using an immunotherapy drug in combination with chemotherapy could prolong survival.


Symptoms of extensive-stage small-cell lung cancer can be categorized by those that affect the lungs, those caused by paraneoplastic syndromes (an abnormal immune response triggered by the tumor), and those related to metastasis.

Symptoms related to the lungs include:

Symptoms of paraneoplastic syndromes include:

  • Muscle weakness in the upper limbs, vision changes, and difficulty swallowing (Lambert-Eaten myasthenic syndrome)
  • Weakness, fatigue, and a low sodium level in the blood (also known as the syndrome of inappropriate antidiuretic hormone secretion, or SIADH)
  • Loss of coordination and difficulty speaking (paraneoplastic cerebellar degeneration)
  • Clubbing (rounding) of the fingernails

Symptoms related to metastasis include:


In the past, the treatment of extensive-stage small-cell lung cancer most commonly involved chemotherapy administered on its own. A 2018 study published in The New England of Journal of Medicine, however, found that first-line therapy (the initial treatment) using the immunotherapy drug Tecentriq (atezolizumab) in combination with the chemotherapy agents carboplatin and etoposide significantly prolonged survival relative to using chemotherapy alone. Due to these findings, the combination was given priority review by the FDA.

Sometimes radiation may be used as a form of palliative therapy to help relieve symptoms, such as bone pain, bleeding of the lungs, airway obstruction, or severe neurological complications.


Survival rates for small cell lung cancer have improved since the addition of radiation therapy to treatment but still remain low.

Without treatment, the average life expectancy for a person with an extensive diagnosis is two to four months. With treatment, the expectancy rises to between six and 12 months, with a median five-year survival rate of up to 4%.

As we have come a long way in treating other fast-growing cancers, such as leukemia, it is hoped that better treatments will be found to treat small cell lung cancer in the near future.


Studies suggest that learning what you can about your lung cancer can improve your quality of life, and possibly even your outcome. Ask questions. Learn about clinical trials. Consider joining a support group.

Many of us hesitate to talk about end-of-life issues, but discussing these with your doctor and your family—even if all of you are hoping for a cure—is associated with fewer feelings of loneliness and a better quality of life.

Never lose hope, even if you have chosen not to pursue further treatment. Hope for quality time with loved ones, with good control of your symptoms. Hope for the future of your loved ones who will remain, with memories of you in their hearts.

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  1. Basumallik N, Agarwa M. Cancer, Lung Small Cell (Oat Cell). StatPearls Publishing. Updated February 14, 2019.

  2. Shirasawa M, Fukui T, Kusuhara S et al. Efficacy and risk of cytotoxic chemotherapy in extensive disease-small cell lung cancer patients with interstitial pneumoniaBMC Cancer. 2019;19(1). doi:10.1186/s12885-019-5367-0

  3. Horn L, Mansfield A, Szczęsna A et al. First-Line Atezolizumab plus Chemotherapy in Extensive-Stage Small-Cell Lung CancerNew England Journal of Medicine. 2018;379(23):2220-2229. doi:10.1056/nejmoa1809064

  4. American Cancer Society. Signs and Symptoms of Lung Cancer. Updated October 1, 2019.

  5. Latimer KM, Mott TF. Lung cancer: diagnosis, treatment principles, and screening. Am Fam Physician. 2015;91(4):250-6.

  6. Iyer P, Ibrahim M, Siddiqui W, Dirweesh A. Syndrome of inappropriate secretion of anti-diuretic hormone (SIADH) as an initial presenting sign of non small cell lung cancer-case report and literature reviewRespir Med Case Rep. 2017;22:164-167. doi:10.1016/j.rmcr.2017.08.004

  7. Tian S, Zhang X, Jiang R et al. Survival Outcomes With Thoracic Radiotherapy in Extensive-Stage Small-Cell Lung Cancer: A Propensity Score-Matched Analysis of the National Cancer DatabaseClin Lung Cancer. 2019;20(6):484-493.e6. doi:10.1016/j.cllc.2019.06.014

  8. Li Y, Ling L, Zhanyu P. Effect of Wellness Education on Quality of Life of Patients With Non–Small Cell Lung Cancer Treated With First-Line Icotinib and on Their Family CaregiversIntegr Cancer Ther. 2019;18:153473541984237. doi:10.1177/1534735419842373

  9. Dalal S, Bruera E. End‐of‐Life Care Matters: Palliative Cancer Care Results in Better Care and Lower CostsOncologist. 2017;22(4):361-368. doi:10.1634/theoncologist.2016-0277

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