A small cell lung cancer (SCLC) misdiagnosis is possible. This can occur because of challenges during the diagnostic tests and because SCLC may share symptoms and causes similar to other conditions.

SCLC has non-specific symptoms, such as coughing and shortness of breath, which can overlap with other lung diseases. Other lung diseases can also share the same causes, such as smoking.

This article looks at why a misdiagnosis of SCLC may be possible, how likely this may be, and when to seek a second opinion.

A healthcare professional discussing a small cell lung cancer misdiagnosis with a patient.Share on Pinterest
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According to a 2019 study, lung cancer is one of the most commonly misdiagnosed types of cancer, with 6.8% of cases of diagnostic errors within primary healthcare.

However, it is unclear how many cases of misdiagnosed lung cancer cases are SCLC specifically.

A misdiagnosis can occur due to challenges during the diagnostic procedures and the non-specific symptoms of lung cancer.

Diagnostic procedures

A 2017 article notes that in 90% of cases, a lung cancer misdiagnosis occurs on chest radiographs. The authors note that errors during diagnosis can occur due to:

  • observer error, such as errors in:
    • scanning
    • decision making
    • recognizing cancer markers
  • tumor characteristics, such as lesion size and location
  • technical aspects, including image quality and patient positioning

Non-specific symptoms

SCLC is difficult to detect in the early stages, due to a lack of symptoms specific to the disease. It shares similar symptoms to many other conditions, which may lead to misdiagnosis.

Symptoms of SCLC include:

Some of these symptoms can overlap with other conditions, such as:

Tuberculosis may be a common misdiagnosis of lung cancer due to shared symptoms, although the condition is uncommon in the United States.

Some lung conditions may also co-occur. Pneumonia may affect 50% to 70% of people with lung cancer and can be one of the first signs of underlying cancer.

SCLC may also share similar causes to other lung diseases. Smoking is a major risk factor for SCLC and the main cause of COPD.

Conditions which may appear similar to SCLC may include:

Research suggests doctors should always consider lung cancer as a potential diagnosis if people smoke or have a history of smoking and have a new cough or cough up blood.

People will undergo extensive testing for an SCLC diagnosis, including biopsy, cytology tests, imaging scans, and laboratory tests.

Getting a second opinion may help confirm a diagnosis and may provide more certainty for people managing and treating the condition they have.

When should a person seek a second opinion?

According to the American Cancer Society (ACS), people may seek a second opinion if:

  • they want peace of mind knowing it is the correct diagnosis and treatment plan
  • they think a doctor has underestimated the severity of their condition
  • they want to know they have explored all the options
  • an initial doctor is unsure of what the underlying condition is
  • they want to speak to a specialist
  • there is uncertainty over the type or stage of cancer
  • there are communication difficulties between a person and a doctor
  • an insurance company wants a second opinion

How to get a second opinion

Healthcare professionals understand it is common to seek a second opinion. People can talk with a doctor about getting a second opinion and ask if they have any recommendations.

People can also contact their insurance provider to check what the policy covers and if a new doctor is part of the health plan.

It is important to have all the details and reports of any diagnostic tests and treatment plans to show a new doctor.

People may want to contact local hospitals, cancer centers, or clinics or look at the following resources for finding a second opinion:

What is the outlook for SCLC?

SCLC is an aggressive form of lung cancer. With treatment, extensive-stage SCLC may have a survival time of 6 to 12 months. Limited-stage SCLC may have a longer survival time of 16 to 24 months.

Treatment may lead to a period of living disease free for around 2 years in around 10% of people with SCLC.

What are the odds of beating SCLC?

SCLC may have a better response to combined chemotherapy and radiation therapy than some other types of lung cancer, although it is difficult to cure.

According to the ACS, the 5-year relative survival rates for SCLC are as follows:

  • Localized: 30%
  • Regional: 18%
  • Distant: 3%

However, this data is from SCLC diagnoses between 2012 and 2018, so the survival rates may have changed since.

As with any other cancer, it may be possible to misdiagnose small cell lung cancer (SCLC) as it has non-specific symptoms that can be similar to other lung conditions.

Doctors will carry out extensive tests to diagnose SCLC. If people want a second opinion, they may choose to look for a specialist in lung cancer diagnosis to confirm any findings.