Small Cell Lung Cancer Pathology

Small cell lung cancer is distinct in several areas from all other types of the disease, collectively referred to as non-small cell lung cancer.  There are several cell types affiliated with non-small cell lung cancer but only one, known as the oat cell, defines small cell lung cancer.  Cases of this disease may also have non-small cell types of cancer cells mixed into the malignancy; these cases are called mixed small cell lung cancer.   It’s the characteristics of the oat cell that provides the unique attributes of small cell lung cancer (SCLC).

Aggressive Nature of Small Cell Lung Cancer

The oat cell got its name from its shape and size; it is shaped like an oat grain and is relatively flat.  Nevertheless, small cell cancers are known for their tendency to spread rapidly and to travel beyond the location of the original tumor early in the development of the disease.  SCLC almost always rises in the bronchi: the tubes that connect the lungs to the trachea.  They are located immediately adjacent to a lymph node which in a lot of SCLC cases is the pathway to remote sites in the body.  Small cell lung cancer can metastasize to other parts of the body before the first symptoms of the disease become apparent.

Impact of Chemotherapy and Radiation

One of the definitive characteristics of this cell is its level of sensitivity to chemotherapy and radiation treatment.  Both forms of therapy are very effective with small cell cancer; in virtually all cases of SCLC surgery is not performed, with chemotherapy and/or radiation being the preferred forms of treatment.  One of the reasons that surgery is precluded is the fact that most cases aren’t diagnosed until the disease has spread to remote locations.   But it is also true that chemotherapy and radiation are more effective with small cell lung cancer than with virtually any other form of malignancy.  In many cases the use of these forms of treatment can lead to eradication of any evidence of malignancy, even in advanced cases. However most cases go into relapse relatively soon after treatment, leading to a poor prognosis despite good early results.

Disorders Triggered by SCLC

In the late 19th century a French physician first identified the occurrence of neurological disorders associated with systemic malignancies.  The term for this phenomenon is paraneoplastic syndrome.  They are defined as “clinical syndromes involving nonmetastatic systemic effects that accompany malignant disease.” In other words, the presence of small cell lung cancer that has spread to remote locations can trigger seemingly unrelated physical malfunctions.

These symptoms are in fact caused by substances produced by the tumor.  They can occur in the gastrointestinal system, the kidneys, the endocrine system, the cardiovascular system, and in other areas of the body such as the outer skin.  One of these conditions associated with SCLC is the Cushing Syndrome, characterized by such abnormalities as upper body obesity and accumulations of fat around the clavicle and on the back.  Other conditions caused by systemic small cell cancer include severe flushing of the face, asthma, and other symptoms brought on through the endocrine system by malignant carcinoid syndrome.

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