How Agent Orange impacts prostate cancer risk, pathology, and treatment outcomes

Abstract

Between 2.6 and 3.8 million veterans served in Vietnam while the US military dispersed Agent Orange (AO), although the exact number of exposed individuals is unknown. Agent Orange, an herbicide, is a known risk factor for various cancers, including sarcoma and leukemia, but less is known about its link with prostate cancer (PC). Prostate cancer is the most commonly diagnosed malignancy in men and the fifth most common cause of cancer-related death in men worldwide. In 2023, approximately 288,300 patients will be given a diagnosis of PC, and an estimated 34,700 fatalities will occur in the United States. However, whether the pathologic characteristics of PC among those exposed to AO differ from those in the general population remains unclear. Our review synthesizes the literature regarding the impact of AO exposure on PC incidence and disease course. A comprehensive PubMed literature search of articles published beginning in 1950 was performed using the primary search terms “Agent Orange,” “TCDD,” and “tetrachlorodibenzodioxin” and the secondary search terms “prostate cancer” or “prostate neoplasm.” The search was limited to studies that focused on human participants and were published in English. Four authors thoroughly reviewed the retrieved articles for relevancy to the study aims: discussion of PC diagnosis, prognosis, or management among patients exposed to AO. Of 108 studies identified in our search, 13 were included in this systematic review. Findings within studies concerning AO exposure with relation to PC incidence, age at diagnosis or treatment initiation, and PC severity seemed to be mixed and generally conflicting. However, the literature seems to indicate that there are no significant differences in survivorship between exposed and unexposed veterans who are given a diagnosis of PC. Given these heterogeneous outcomes, the evidence does not encourage a significantly different approach to the diagnosis and management of PC for veterans exposed to AO. Clinicians should make case-by-case decisions regarding PC screening and potential treatment options for this patient group, weighing clinical suspicion against the harms of diagnostic workup and treatment.

Keywords

Agent Orange / 2,3,7,8-Tetrachlorodibenzo-p-dioxin / Prostate cancer / Veterans

Author summay

Awais Paracha and Zohair Siddiqui contributed equally to this work.

Acknowledgments

None.

Statement of ethics

Not applicable.

Conflict of interest statement

The authors declare no conflicts of interest.

Funding source

None.

Author contributions

AP, ZS: Conceptualization, methodology, writing-original draft, writing-review and editing;

AA: Methodology, writing-original draft, writing-review and editing;

ED, FW: Writing-original draft, writing-review and editing;

ZH: Conceptualization, supervision, writing-review and editing.

Data availablility

The datasets generated during and/or analyzed during the current study are not publicly available, but are available from the corresponding author on reasonable request.

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