DE-170 and Saipan: Asbestos Exposure Among World War II Naval Veterans

Imagine a 19-year-old machinist's mate in 1944, working in the engine room of a destroyer escort somewhere in the Pacific Theater, scraping old pipe insulation to make a repair before the next engagement. He breathes in clouds of white fiber dust, thinks nothing of it, and returns to his bunk. Forty years later, he develops a persistent cough and chest pain. The diagnosis: pleural mesothelioma, a cancer directly linked to that dust he inhaled decades ago. This is the story of thousands of World War II naval veterans.

DE-170, designated USS Coolbaugh, was a John C. Butler-class destroyer escort commissioned by the U.S. Navy in 1944. Like virtually every American warship of that era, it was built with extensive use of asbestos-containing materials. The Navy relied on asbestos for its exceptional heat resistance and fire-retardant properties, installing it in boiler rooms, engine spaces, pipe lagging, gaskets, deck tiles, and crew berthing areas. Sailors aboard DE-class vessels and stationed at Pacific bases such as Saipan faced repeated, often daily, exposure to asbestos fibers during normal operations, maintenance, and battle damage repair.

The connection between this wartime service and a fatal cancer diagnosis decades later is now well established. According to the National Cancer Institute, mesothelioma has a latency period of 20 to 50 years, meaning the men who served in the Pacific in 1944 and 1945 were at peak diagnostic risk from the 1970s through the early 2000s. The U.S. Department of Veterans Affairs recognizes asbestos exposure during military service as a presumptive risk factor for mesothelioma, making veterans eligible for disability compensation and specialized healthcare.

Understanding the specific circumstances aboard ships like DE-170 and at forward operating bases such as Saipan helps patients, families, and legal advocates reconstruct the exposure history that's essential for both medical care and VA benefits claims. As one occupational medicine specialist put it, "The Navy didn't know they were poisoning their own men. But the asbestos industry knew, and that distinction matters enormously in court and in the clinic."

Asbestos exposure aboard WWII naval vessels produced several distinct patterns of disease, depending on the type of work a sailor performed and how long they served. The most common asbestos-related conditions seen in this veteran population include the following.

Pleural Mesothelioma is the most frequently diagnosed malignancy linked to naval asbestos exposure. It arises in the lining of the lungs (the pleura) and accounts for roughly 75% of all mesothelioma cases, according to the American Cancer Society. Sailors who worked in engine rooms, boiler spaces, or performed any insulation work were at highest risk.

Peritoneal Mesothelioma affects the lining of the abdomen and accounts for approximately 20% of cases. It's associated with higher-dose or longer-duration exposures, often seen in shipyard workers and career naval personnel who served on multiple vessels over many years.

Asbestosis is a chronic, non-cancerous scarring of the lung tissue caused by inhaled asbestos fibers. While not cancer, it's a serious progressive condition that causes permanent breathing impairment. According to the Agency for Toxic Substances and Disease Registry (ATSDR), asbestosis typically requires 10 or more years of significant exposure, making career Navy veterans particularly vulnerable.

Pleural Plaques and Pleural Thickening are benign markers of past asbestos exposure that appear on imaging studies. They don't cause cancer themselves but serve as important diagnostic indicators that a veteran's lungs were exposed to asbestos, which can support both medical and legal claims.

One of the most dangerous features of asbestos-related diseases is that they produce few or no symptoms for decades after exposure. By the time a veteran notices something is wrong, the disease is often already advanced. The symptoms themselves are easy to misattribute to aging, smoking history, or other respiratory conditions, which is why mesothelioma is frequently diagnosed at a late stage.

For pleural mesothelioma, the most common presenting symptoms include shortness of breath (dyspnea), persistent chest pain or pressure, a dry or productive cough, and fatigue. According to the Mayo Clinic, approximately 60% of pleural mesothelioma patients present with a pleural effusion, a buildup of fluid around the lung that causes the feeling of breathlessness even at rest.

• Shortness of breath, often worsening gradually over months
• Chest pain, typically on one side, that doesn't resolve with rest
• Persistent cough that may produce blood-tinged mucus
• Unexplained weight loss of 10 or more pounds
• Fatigue and weakness disproportionate to activity level
• Fever and night sweats in some patients
• Abdominal swelling or pain if peritoneal involvement is present

If you're a veteran who served aboard Navy vessels during or after World War II and you're experiencing any of these symptoms, your doctor needs to know about your service history. Mentioning shipboard duty is critical because it directly informs the differential diagnosis. Many primary care physicians don't automatically screen for occupational asbestos exposure unless the patient mentions it.

The causal chain between service aboard a ship like DE-170 and a mesothelioma diagnosis 40 years later is direct and scientifically unambiguous. Asbestos is a naturally occurring silicate mineral that, when disturbed, releases microscopic fibers into the air. These fibers, once inhaled, lodge permanently in the pleural lining of the lungs. Over decades, the fibers cause chronic inflammation and DNA damage that eventually triggers malignant transformation, according to research published in the journal Nature Reviews Cancer (Carbone et al., 2019).

Aboard WWII-era destroyer escorts and at forward bases like Saipan, asbestos was present in several specific forms. Thermal insulation wrapped around steam pipes and boiler systems often contained chrysotile or amphibole asbestos at concentrations of 30% to 100% by weight. Gaskets, packing materials, and valve insulation used in engine rooms were frequently made from asbestos-reinforced materials. Deck tiles, bulkhead insulation, and overhead lagging in crew berthing areas added additional exposure pathways.

At the Saipan base complex, which the U.S. captured from Japan in July 1944 and immediately converted into a major forward logistics and air operations hub, construction and repair activities generated significant asbestos exposure. Prefabricated Quonset huts and temporary structures used asbestos-containing roofing materials. Naval repair facilities servicing damaged ships at Saipan would have required stripping and replacing damaged insulation, one of the highest-exposure tasks in any shipboard environment.

The Navy was aware of asbestos hazards in general industrial settings as early as the 1930s, but the urgency of wartime production and the absence of effective protective equipment meant that sailors were given no meaningful protection from fiber inhalation during the war years. The ATSDR notes that even brief, high-intensity exposures to asbestos can be sufficient to cause mesothelioma decades later.

Consider a veteran who served aboard a Pacific Fleet destroyer escort in 1944 and 1945, now in his 80s, presenting to a VA medical center with a two-month history of worsening shortness of breath and right-sided chest pain. A chest X-ray reveals a large pleural effusion. This is a classic presentation, and the workup that follows is now well-standardized.

Diagnosing mesothelioma in a WWII veteran begins with a thorough occupational and service history. Physicians need to know the ships a veteran served on, their job rate (machinist's mate, boilerman, damage control specialist, etc.), and any shore-based postings that involved construction or repair work. This history directly informs the pre-test probability of an asbestos-related diagnosis.

Imaging studies are the first step. A chest X-ray may reveal pleural thickening, pleural plaques, or a pleural effusion. A CT scan of the chest provides much greater detail, showing the characteristic rind-like pleural thickening that's typical of mesothelioma. According to the National Cancer Institute, CT imaging can also reveal mediastinal lymphadenopathy and help stage the disease.

Tissue biopsy remains the definitive diagnostic step. Options include thoracoscopic biopsy (using a camera inserted through the chest wall), CT-guided needle biopsy, or analysis of pleural fluid obtained by thoracentesis. Pathological diagnosis requires immunohistochemical staining to distinguish mesothelioma from other pleural malignancies, particularly metastatic adenocarcinoma. Markers including calretinin, WT-1, and D2-40 are characteristically positive in mesothelioma, according to the College of American Pathologists guidelines.

Blood biomarkers including MESOMARK (soluble mesothelin-related peptides) and fibulin-3 have shown promise as adjunctive diagnostic tools, though they're not yet used as standalone tests. A 2012 study in the New England Journal of Medicine (Bhatt et al.) demonstrated that fibulin-3 levels distinguished mesothelioma patients from asbestos-exposed controls with high sensitivity.

Treatment for mesothelioma diagnosed in WWII veterans follows the same protocols used for all patients, though the advanced age of this population (most surviving WWII veterans are now in their late 90s, though many diagnoses occurred in the 1980s and 1990s when veterans were in their 60s and 70s) often influences which therapies are appropriate. A multimodal approach combining surgery, chemotherapy, and radiation offers the best outcomes for eligible patients.

Surgery is most beneficial for patients with early-stage disease and good functional status. Pleurectomy and decortication (P/D) removes the diseased pleural lining while preserving the lung. Extrapleural pneumonectomy (EPP) removes the lung entirely along with the pleura, diaphragm, and pericardium. According to a 2018 analysis published in JAMA Oncology, P/D is increasingly preferred over EPP because it carries a lower operative mortality rate while providing comparable survival benefits.

Chemotherapy with the combination of cisplatin and pemetrexed (Alimta) remains the standard first-line systemic therapy, having been approved by the FDA in 2004 specifically for mesothelioma. The pivotal Phase III trial (Vogelzang et al., 2003, published in the Journal of Clinical Oncology) demonstrated that this combination extended median survival from 9.3 months with cisplatin alone to 12.1 months, with 41% of patients achieving a partial or complete response.

Immunotherapy has transformed the treatment landscape since 2020. The FDA approved the combination of nivolumab (Opdivo) plus ipilimumab (Yervoy) for unresectable pleural mesothelioma in October 2020, based on the CheckMate 743 trial, which showed median overall survival of 18.1 months compared to 14.1 months with chemotherapy alone. This represents the most significant survival improvement seen in mesothelioma in nearly two decades.

Veterans receiving treatment through the VA healthcare system have access to these therapies at VA medical centers with oncology programs. The VA also covers clinical trial participation at affiliated academic medical centers.

Prognosis for mesothelioma remains serious. According to the American Cancer Society, the five-year relative survival rate for all stages of pleural mesothelioma is approximately 12%. However, these statistics reflect historical data and don't fully capture the impact of newer immunotherapy regimens approved since 2020. Patients diagnosed today, particularly those eligible for combination immunotherapy, may have meaningfully better outcomes than these figures suggest.

Stage at diagnosis is the strongest prognostic factor. Patients diagnosed at Stage I or II, when the disease is still confined to one side of the chest, have significantly better outcomes than those diagnosed at Stage III or IV with lymph node involvement or distant metastasis. Unfortunately, because of mesothelioma's long latency period and non-specific early symptoms, the majority of patients present with advanced-stage disease. The NCI's SEER database indicates that only about 22% of mesothelioma cases are diagnosed at a localized stage.

Cell type also matters significantly. Epithelioid mesothelioma, the most common subtype, carries the best prognosis, with median survival of 12 to 27 months in various series. Sarcomatoid mesothelioma is the most aggressive variant, with median survival often under 6 months. Biphasic tumors, which contain both cell types, fall between these extremes. For WWII veterans, who often carried significant comorbidities from age, smoking history, or other service-related conditions, performance status at diagnosis plays a critical role in determining treatment eligibility and outcome.

A mesothelioma diagnosis changes everything, but veterans and their families have access to a network of support resources that civilians may not. The VA's Caregiver Support Program provides stipends and respite care for family members who take on primary caregiving responsibilities. The Veterans Benefits Administration processes disability claims for mesothelioma under 38 CFR 3.309, which includes asbestos-related diseases as a recognized service-connected condition.

Palliative care, which focuses on symptom management and quality of life rather than cure, is an essential component of mesothelioma care at every stage. Pleural effusions can be managed with repeated thoracentesis or a permanent indwelling pleural catheter, which patients can drain at home. Pain management, pulmonary rehabilitation, and nutritional support all contribute to maintaining function and dignity during treatment.

Legal options deserve serious consideration. Asbestos manufacturers knew their products were dangerous long before the Navy was informed. Asbestos trust funds, established through bankruptcy proceedings by companies like Johns Manville and Owens Corning, have paid out over $30 billion to asbestos victims since the 1980s. Veterans may be eligible for both VA compensation and civil trust fund claims simultaneously. Consulting with an attorney who specializes in mesothelioma litigation is an important step for most diagnosed veterans and their families.