Understanding Squamous Cell Carcinoma: Symptoms, Causes & Diagnosis

Medically Reviewed by Millie Das, MD
Written by J. GuanJan 2, 20243 min read
NSCLC Subtypes

Types of non-small cell lung cancer subtypes. Images adapted from Wikimedia Commons.

This article will provide an overview of squamous cell carcinoma (SCC). It is a type of non-small cell lung cancer (NSCLC) characterized by more local invasion within the lung. It accounts for about 30% of all NSCLC cases. SCC is closely associated with tobacco smoking, underscoring the importance of awareness among smokers and non-smokers. It predominantly affects males rather than females. These risks amplify the importance of early detection and treatment. Individuals can proactively fight this disease by understanding the symptoms, causes, and diagnosis of SCC.

What is squamous cell carcinoma?

Squamous cells are flat cells that form the lining of inner lung airways. SCC can occur in other organs covered with squamous cells, such as the skin, lips and mouth, esophagus, prostate, urinary tract, vagina and cervix. In the case of lung cancer, SCC usually starts from the large bronchi (main airways connecting the trachea to the lungs).

Symptoms

Compared to other lung cancer types, SCC can present with earlier onset of symptoms. With the SCC growing near the main airways, symptoms like a persistent cough, shortness of breath, wheezing, bloody cough and difficulty swallowing may manifest at an early stage.

The common symptoms that occur in all types of lung cancer (including SCC) are

  • Persistent cough
  • Shortness of breath (dyspnea)
  • Fatigue
  • Coughing up blood (hemoptysis)
  • Chest pain
  • Weight loss
  • Change in voice (hoarseness)
  • Wheezing when breathing and coughing

Related: Feeling Breathless? Do Not Ignore the Signs of Lung Cancer

Causes and risk factors

Among all types of NSCLC, squamous cell carcinoma is intrinsically associated with tobacco smoking, with up to 91% of SCC attributed to cigarettes. Also, the risk level increases proportionally to the number of cigarettes smoked daily.

Other risk factors that can cause SCC include radon, secondhand smoke, family history, air pollution and genetic predisposition.

Related: New updates of lung cancer risk factors that you need to know

Detect & diagnosis

Lung cancer is usually picked up by detection methods involving imaging of the chest, such as chest X-ray, CT scan, PET scan, MRI and ultrasound. But these methods are not definitive enough to distinguish adenocarcinoma from other subtypes.

A definite diagnosis of SCC involves the assessment of tumor biopsy under the microscope. This histopathology process in lung cancer diagnosis may include morphological characterization, immunohistochemistry and often, molecular or genetic tests (biomarker tests).

It is now recommended for everyone with metastatic NSCLC (NSCLC that has spread) have their tumor tested for biomarkers. These tests provide information on the cancer-driving mutations which can be actionable targets in precision medicine and immunotherapy. The probability of finding a cancer-driving mutation is higher in people with non-squamous lung cancer. Nevertheless, people with SCC may also have an actionable biomarker, particularly those are younger in age or have a light or never smoking history.

A comprehensive histopathology report will contain the biopsy site, tumor size, cancer stage, identified subtype with the morphology descriptions, IHC results, molecular profile (if any), and pathologist’s comment.

Biopsy methods to obtain a tumor sample include bronchoscopy, needle and surgery.

Thankfully, the incredible strides in cancer research have provided individuals with various ways to detect and diagnose this disease. It is important to stay informed and prioritize our health and well-being. Regular check-ups are key and if there are noticeable symptoms related to SCC, do not hesitate to consult a doctor immediately. It may be frightening, burdensome and concerning, but rely on medical professionals to offer all the support and guidance you need.

Share this article:

This article has been medically reviewed and fact-checked to ensure our content is informed by the latest research in cancer, global and nationwide guidelines and clinical practice.

Click here for more information.