Primary immunodeficiency diseases (PIDD) are a group of more than 300 disorders caused by single-gene defects that prevent the immune system from functioning properly.

These immune disorders affect 1 in 1,200 people, and an association between these diseases and cancer has been noted.

A team of researchers at Roswell Park Cancer Institute recently found an increased incidence of certain types of cancer, particularly lymphoma, in patients with PIDD.

Their findings, published online ahead of print in the Journal of Allergy and Clinical Immunology, reveal a restricted but important role for the immune system in protecting against certain types of cancer.

The Roswell Park investigators evaluated the incidence of cancer among patients with PIDD registered in the United States Immune Deficiency Network (USIDNET).

This registry, the largest of its kind, is a research program of the Immune Deficiency Foundation that gathers information regarding the history and outcomes of patients with PIDD.

The study compared rates of cancer in USIDNET patients with those for the general population using data from the Surveillance, Epidemiology and End Results Program (SEER) of the National Cancer Institute, a population-based registry collecting cancer data throughout the United States.

They compared overall and site-specific rates of cancer in 3,658 PIDD patients and an age-adjusted SEER population, making this the largest study of its kind.

The team found a 42% increase in overall cancer incidence among patients with PIDD.

The majority of cancers (70%) were noted in patients with common variable immunodeficiency (CVID), followed by hypogammaglobulinemia and agammaglobulinemia (9%) and Wiskott-Aldrich syndrome (4.6%).

The cancer types with the highest incidence rates among PIDD patients in the USIDNET registry were lymphoma, skin cancer and thyroid cancer.

The researchers found that incidence of lymphoma was 10 times higher among men and 8 times higher among women, and concluded that this excessive lymphoma risk was largely driven by CVID.

Compared with the general population, men with PIDD were more likely to be diagnosed with skin and thyroid cancer, whereas women with PIDD were more likely to be diagnosed with skin and stomach cancer.

Patients with PIDD did not have increased incidence of the most common types of solid tumours: lung, breast, colon and prostate.

“We found that patients with primary immunodeficiency have a modest but significant increase in the overall incidence of cancer. Although we did not observe an increased risk of the most common solid-tumour malignancies, we did find that patients with specific forms of primary immunodeficiency diseases are predisposed to certain types of cancers,” says senior author Brahm Segal, MD, Chief of Infectious Diseases and Member of the Department of Immunology at Roswell Park. “Cancers observed with higher frequency in patients with PIDD were generally associated with an infectious cause, such as Epstein-Barr virus-associated lymphoma. Our results point to a restricted role of the immune system in protecting against specific cancers, and underscore the need for evidence-based approaches for early detection in high-risk PIDD patients.”

“One of the many functions of the immune system is to recognise and eliminate cancerous or precancerous cells in the body in order to prevent cancer from developing,” adds first author Paul Mayor, MD, MS, Fellow in Roswell Park’s Department of Gynecologic Oncology. “Our study demonstrates that patients with primary immunodeficiency diseases have an increased risk of certain cancers, which adds to our understanding of the role of the immune system and immunosurveillance in the risk of cancer among those with a compromised immune system.”

Source: Roswell Park