The typical mesothelioma latency period is 20 to 50 years, with recent studies finding a median of 30 to 45 years. Under normal circumstances, the shortest possible latency period is 10 to 15 years, while the longest is more than 50 years. The time period depends on a number of factors such as the duration and intensity of asbestos exposure, as well as the patient’s gender and the type of mesothelioma. Because of this long time span, most of those who are diagnosed with mesothelioma and other asbestos-related disease are in their 60s or 70. Those diagnoses come after symptoms of the disease — a persistent cough or difficulty breathing — become nagging or debilitating.
Studies show that lower exposure levels and shorter durations of exposure can lead to longer latency periods. Conversely, individuals with high levels of exposure for long periods of time have significantly shorter latency periods.
The latency period typically continues until later stages of the disease, when symptoms finally begin and a doctor can diagnose the patient. For most illnesses, a latency period begins when an individual is exposed to a virus or other illness-inducing entity and ends when the person first begins experiencing symptoms. Although some experts use this definition for mesothelioma latency period, most agree this asbestos-related cancer is considered latent until it is actually diagnosed.
This is because symptoms of mesothelioma can actually arise before a patient has the cancer. Asbestosis, a non-cancerous illness caused by asbestos, has many of the same symptoms and is often a precursor to mesothelioma. So a patient suffering from asbestosis could have mesothelioma-like symptoms such as a persistent cough and chest pain before the cancer manifests itself.
At these later stages, the cancer is more difficult to treat and the patient generally has a shorter life expectancy. But a prompt diagnosis followed by immediate treatment can lead to an improved prognosis.