Why Can Small Cell Lung Cancer Be Challenging To Treat?

Small cell lung cancer (SCLC) makes up roughly 13 percent of all lung cancers. Lung cancer is the second most common cancer among men and women and is the number 1 cause of cancer-related death among both men and women in the United States.¹

How do SCLC treatments differ?

New treatment advancements have historically been slower for SCLC compared to non-small cell lung cancer (NSCLC), although progress has picked up in recent years.⁷ SCLC can be hard to treat for a variety of reasons. These challenges contribute to the lethality of the disease, which is devastating.

It is important to remember that everyone's cancer experience is different and statistics do not often tell the whole story. Be sure to talk with your doctor about different SCLC treatment options.

Here, we examine 4 general reasons why SCLC can be hard to treat and can present a challenge to both doctors and those diagnosed with lung cancer.

1) It is aggressive and spreads quickly

SCLC is an aggressive tumor that spreads quickly and early in the disease. This makes surgery to remove it hard and sometimes impossible.

Cancer medicine is based on targeting parts of the cancer cell or building blocks in order to stop its growth and eventually kill it. In SCLC, parts of the building blocks are different or missing, making it hard for doctors to find medicine to treat and kill the tumors.^2-4

There are some medications that are used to treat SCLC. Many people with SCLC have a good response to these medications at first. Unfortunately, SCLC often recurs and treatment after the first time is not as successful.³

2) Screening is not as widely available as some cancers

Unlike some cancers, SCLC does not have widespread screening. The only screening available to date is a low-dose computed tomography (CT) scan, which uses a small amount of radiation to take pictures of the lungs. Yearly screening is recommended only for certain adults at high risk, such as people ages 50 to 80 with a significant smoking history.⁴

Unfortunately, there are flaws to this type of screening. Some of these include:⁴

• Suggesting a person has cancer who does not.
• Finding other cancers that may have never caused problems.
• Radiation over time, even in small doses, can cause cancer in people who are otherwise healthy.

3) Symptoms of the disease may be missed

Symptoms of SCLC are often not specific and people may not go to the doctor for the symptoms they are having. Also, screening is recommended only for people who meet certain age and smoking history criteria, so many people are never screened. The combination of these factors makes it easier for SCLC to go undetected.^4,5

4) New treatments have been slow to arrive, but progress is picking up

Cancer treatments are constantly evolving. For many years, SCLC lagged behind other cancers, and new treatment options did little to change overall survival. That has started to change. Since 2019, the U.S. Food and Drug Administration (FDA) has approved several new options for SCLC, including:^7-10

• Immunotherapy combined with chemotherapy as a first treatment for extensive-stage SCLC
• Imfinzi® (durvalumab) after chemotherapy and radiation for limited-stage SCLC
• Imdelltra® (tarlatamab-dlle) for extensive-stage SCLC that has gotten worse during or after platinum-based chemotherapy
• Zepzelca® (lurbinectedin) with Tecentriq® (atezolizumab) as maintenance treatment for extensive-stage SCLC that has not gotten worse after first treatment with Tecentriq and chemotherapy

In clinical trials, each of these treatments helped people live longer than standard treatment or a placebo.^7-10

There are many factors that need to be considered when looking at why SCLC is hard to treat. Improving early detection, screening, and treatment options will be a big step in the right direction for improving treatment and overall survival of SCLC. Recent advances are encouraging. But for those with SCLC and for those who love them, progress cannot come soon enough.⁶

Researchers are hopeful

Doctors and researchers say the pace of new drug development for SCLC has noticeably picked up. Newer treatments, including additional immunotherapies and a type of targeted drug called an antibody-drug conjugate, are being studied in clinical trials. It is important for doctors and researchers to keep moving forward in order to make new treatment options available to those living with SCLC.⁷