Skin Cancer in an Atomic Veteran: Cause or Coincidence?

Epidemiology of ocular surface squamous neoplasia in veterans: a retrospective case-control study

Background

A number of risk factors have been evaluated in ocular surface squamous neoplasia, but few studies have assessed risk factors specific to the armed forces veteran population.

Methods

We conducted a retrospective case-control study on 55 patients and 55 age-matched controls with biopsy-proven ocular surface squamous neoplasia from the Miami Veterans Administration Hospital Eye Clinic to investigate potential risk factors encountered by veterans, including service-specific exposures. Veteran-specific risk factors included ionizing radiation exposure, Agent Orange exposure, deployment to Southwest Asia, and exposure to the series of biochemical warfare tests known as Project Shipboard Hazard and Defense. Data was analyzed with SPSS (SPSS Inc., Chicago, IL) using t-tests, chi-squared, and logistic regression analysis, with a p-value of < 0.05 considered statistically significant.

Results

The strongest risk factor for ocular surface squamous neoplasia was lifetime sun exposure both directly assessed via historical quantification of exposure by dermatology practitioners (Odds Ratio (OR) 5.4, 95% Confidence Interval (CI) 2.27–12.847, p < 0.005), and using the surrogate markers of basal cell carcinoma (OR 3.157, 95% CI 1.286–7.748, p = 0.010) and pingueculae (OR 5.267, 95% CI 2.104–13.186, p < 0.005). Of the veteran-specific risk factors, Agent Orange exposure and Southwest Asia deployment were not associated with an increased risk of ocular surface squamous neoplasia. Exposure to ionizing radiation and involvement in Project Shipboard Hazard and Defense were not documented among any cases or controls.

Conclusions

The results of our study are consistent with prior established risk factors, namely highlighting the important role of sun exposure in ocular surface squamous neoplasia among veterans.

Ionizing Radiation Exposure and Basal Cell Carcinoma Pathogenesis

This commentary summarizes studies showing risk of basal cell carcinoma (BCC) development in relationship to environmental, occupational and therapeutic exposure to ionizing radiation (IR). BCC, the most common type of human cancer, is driven by the aberrant activation of hedgehog (Hh) signaling. Ptch, a tumor suppressor gene of Hh signaling pathway, and Smoothened play a key role in the development of radiation-induced BCCs in animal models. Epidemiological studies provide evidence that humans exposed to radiation as observed among the long-term, large scale cohorts of atomic bomb survivors, bone marrow transplant recipients, patients with tinea capitis and radiologic workers enhances risk of BCCs. Overall, this risk is higher in Caucasians than other races. People who were exposed early in life develop more BCCs. The enhanced IR correlation with BCC and not other common cutaneous malignancies is intriguing. The mechanism underlying these observations remains undefined. Understanding interactions between radiation-induced signaling pathways and those which drive BCC development may be important in unraveling the mechanism associated with this enhanced risk. Recent studies showed that Vismodegib, a Smoothened inhibitor, is effective in treating radiation-induced BCCs in humans, suggesting that common strategies are required for the intervention of BCCs development irrespective of their etiology.

Marjolin's ulcer revisited--basal cell carcinoma arising from grenade fragments? Case report and review of the literature

BACKGROUND

Marjolin's ulcer is a rare and often aggressive cutaneous malignancy arising in previously traumatized or chronically inflamed skin.

METHOD

CASE REPORT

A 79-year-old World War II veteran developed basal cell carcinoma (BCC) at the site of a war wound. The tumour developed in relation to several metal grenade fragments. With a disease-free interval of 61 years between injury and onset of complications the patient had one of the longest latency periods of tumour development described so far.

RESULTS

Review of the literature reveals only five cases of relation between grenade fragments and malignancy formation. Presence of foreign bodies has been described as possible aetiology for malignancy development. Explosives and additives contain several mutagenic and tumourigenic substances. We hypothesize a causal connection between the grenade fragments and the development of BCC. Considering the long period of latency between injury and tumour development we suggest grenade injury with left fragments in soft tissue to be a new origin of Marjolin's ulcer.