Mesothelioma Latency Period

How Long Does Mesothelioma Take to Develop?

Mesothelioma caused by asbestos exposure typically takes 20 to 50 years to develop. It is very rare to have a latency period of less than 15 years, while the longest cases have been around 60 to 70 years.

An overwhelming majority of people diagnosed with mesothelioma and other asbestos-related diseases are in their 60s or 70s. They were typically exposed to asbestos in the workplace as adults, and it took decades for their cancer to develop. These diagnoses come after common symptoms of the disease — persistent coughing and difficulty breathing — become nagging or debilitating.

Studies show lower asbestos 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.

Factors That Impact Latency Period

Recent studies conflict on what affects mesothelioma’s latency period and what is merely associated, but most research agrees that the duration and intensity of asbestos exposure have a direct impact.

Duration and Intensity of Asbestos Exposure

Exposure to extremely high levels of asbestos can lead to a shorter mesothelioma latency period, even if the duration of exposure is only a few months. Because of this, individuals at risk of having the shortest latency periods include first responders.

Some paramedics, firefighters and police officers who worked immediately after the World Trade Center terrorist attacks and during Hurricane Katrina have already developed mesothelioma from short-term, high-level asbestos exposure.

Like exposure to high levels of asbestos, exposure for longer periods of time can also shorten the expected latency period. Consequently, people with a history of heavy occupational exposure typically experience shorter-than-average latency periods. One study found it was shortest in insulation workers, who experienced an average latency period of slightly less than 30 years.

Fiber Type

Shorter latency periods are observed among people exposed to crocidolite asbestos. For example, workers and residents of the crocidolite mining district of Western Australia have shown shorter latency periods compared to people exposed to other types of asbestos.

Occupation

More than 75 occupations put workers at risk of asbestos exposure. Of these occupations, certain jobs exposed workers to high concentrations of asbestos. People with extensive exposure to asbestos — whether through short-term, high-concentration exposure or long-term, moderate-concentration exposure — may exhibit shorter latency periods.

Some of these high-risk occupations include jobs in:

• Insulation
• Boiler maintenance
• Shipyards
• Factories
• Power plants
• Textile mills
• Asbestos mining and processing

Secondhand Exposure

Secondhand asbestos exposure happens when someone directly exposed to asbestos accidentally exposes others to asbestos fibers remaining on their body or their clothing.

People who work with asbestos may bring the toxic fibers home on a regular basis, posing a threat to family members. This results in low-level asbestos exposure that is associated with longer latency periods than direct, heavy exposure.

Characteristics Associated with Latency Period

Certain characteristics of mesothelioma are correlated with the disease’s latency period. For example, the cancer’s location and a patient’s age and gender are associated with varying latency periods.

Cancer Location

Some researchers estimate the latency period is longest for pleural mesothelioma — about 30 to 60 years — while the latency period for peritoneal mesothelioma typically falls between 20 and 40 years.

One Australian study published in the Scandinavian Journal of Work, Environment & Health showed that women with peritoneal mesothelioma had an average latency period of just under 30 years. Men with the peritoneal type averaged a 38.8-year latency period, compared to 44 years for pleural cases.

Gender

Some studies suggest that women see a slightly longer mesothelioma latency compared to men. Researchers hypothesize this is a result of overall lower exposure levels in women.

Historically, men have been exposed to asbestos while working in occupations such as construction, power generation and manufacturing. These jobs exposed workers to heavy concentrations of asbestos for long durations.

Women are most often linked to secondhand asbestos exposure. These were lower-exposure doses that lasted for shorter periods of time, which is associated with longer latency periods. The type of mesothelioma and age of the patient can affect these numbers.

Age

Some researchers suspect age at the time of exposure may impact latency, but there are no studies investigating the science behind the potential connection.

The immune system functions less optimally as people age. Theoretically, the older someone is at the time of exposure, the harder it could be for the body to eliminate asbestos fibers or control the damage they cause, potentially leading to shortened latency.

Conversely, asbestos exposure risk is higher in children because they are more active and breathe at higher rates than adults. A 2013 research study from the U.K. government’s Committee on Carcinogenicity showed that a 5-year-old child’s lifetime risk of developing mesothelioma is approximately five times greater than that of a 30-year-old adult.

If a person is exposed to asbestos at a young age, it is possible for that individual to breath in heavier amounts of toxic fibers than an adult would, potentially leading to a shortened latency.

Latency Period and Diagnosis

Symptoms of mesothelioma — such as shortness of breath, chest pain and fatigue — may not appear until the cancer is in stage 3. Because asbestos exposure occurred 20 to 50 years ago in most cases, many patients overlook it when considering possible causes of their illness. This often leads to an initial misdiagnosis.

Delayed onset of symptoms and late diagnosis are what most contributes to a poor mesothelioma prognosis for many people. Patients have the greatest chance at long-term survival when they are diagnosed in earlier stages of the disease and receive aggressive treatment aimed to put the cancer into remission.

Seeking a second opinion from a mesothelioma specialist is highly recommended. These doctors have the most experience and use the latest treatment options to extend life expectancy.