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Proton beam therapy provides precise treatment with minimal damage to surrounding tissues. Proton beam therapy is an effective treatment for periocular skin cancer due to its precise targeting ability, reducing damage to healthy eye structures.
Traditional radiation therapies can damage ocular structures due to less precise energy delivery. The precision of proton beams allows for targeted treatment of cancerous tissues while minimizing exposure to healthy tissues, thereby reducing collateral damage.
The application of proton beam therapy in treating periocular skin cancer represents a significant advancement in cancer treatment modalities. This therapy leverages the unique physical properties of protons, such as their ability to release energy at precise depths (Bragg peak), allowing for the targeted destruction of tumors while sparing surrounding healthy tissues.
According to Yingying Zhang et al., "Proton beam therapy’s sharp lateral penumbra allows for sparing of normal tissues, such as the cornea, whereas the zero-exit dose of the proton’s Bragg peak allows for the sparing of normal tissues such as the optic nerve and retina beyond the target."
These characteristics are particularly advantageous in treating periocular tumors, where maintaining ocular function is a priority. The precision in targeting means that structures like the optic nerve can be protected, significantly reducing the risk of vision impairment.
Proton beam therapy is associated with high local control rates and minimal ocular toxicity. The treatment yields high local control of tumors while preserving vision, making it an ideal choice for patients with periocular skin cancer. Patients treated with proton therapy experienced minimal acute and late toxicities, maintaining functional vision.
The Massachusetts General Hospital study shows that proton beam therapy effectively manages advanced periocular skin cancer, achieving a 100% local control rate over a median follow-up of 96 months. Notably, no patients required orbital exenteration, and functional vision was preserved in all cases.
This success rate is supported by the therapy's ability to limit acute and late toxicities, with no patients experiencing grade 3 or higher effects. Minor side effects such as fatigue and erythema were present but manageable.
Judith A. Adams et al. noted, "Functional vision was maintained in all patients, and no patient required orbital exenteration or enucleation," highlighting the therapy’s advantage in preserving quality of life.
Proton therapy offers a less invasive alternative to surgical interventions like orbital exenteration. Compared to traditional methods, proton therapy spares patients from invasive surgeries and their associated complications. Orbital exenteration can severely impact patients' quality of life, making non-invasive alternatives like proton therapy preferable.
Traditional treatments for advanced periocular skin cancer, such as orbital exenteration, involve the removal of the eye and surrounding structures, often leading to significant physical and emotional distress for patients. Proton beam therapy offers a non-invasive alternative that can achieve similar tumor control without such drastic measures.
This less invasive approach not only preserves ocular structures but also reduces recovery time and post-treatment complications. For patients who may not be candidates for surgery, or who wish to avoid potential negative outcomes, proton therapy provides a viable and effective option.
Alessandra A. Woo et al. emphasized, "Protons enable long-term tumor control with eye sparing in patients with locally advanced periocular skin cancers," demonstrating a clear preference for this method when feasible.
Zhang, Y., Lima, I. C. S., Woo, A. A., Zieminski, S., Adams, J. A., Hughes, M. A., & Chan, A. W. (2025). Proton beam therapy for advanced periocular skin cancer: An eye-sparing approach. Cancers, 17(2), 327.