Photodynamic Therapy For High-Grade Dysplasia

The role of photodynamic therapy for high-grade dysplasia has changed as endoscopic technology and clinical evidence have developed. In patients with Barrett’s oesophagus, high-grade dysplasia signals a substantial risk of progression to oesophageal adenocarcinoma, so treatment aims to remove abnormal tissue while preserving swallowing function and quality of life.

Photodynamic therapy (PDT) combines a light-sensitive medicine with carefully delivered endoscopic light. The activated agent produces reactive oxygen that damages dysplastic cells and small blood vessels. It was once an important non-surgical treatment for Barrett’s-related high-grade dysplasia, although radiofrequency ablation (RFA), endoscopic mucosal resection (EMR) and endoscopic submucosal dissection now influence many treatment decisions.

For Australian clinicians, the practical question is rarely whether PDT has biological value. It is whether its benefits outweigh its limitations for a particular patient, within a specialist service that can provide accurate staging, follow-up endoscopy and multidisciplinary care. The scientific programme and educational resources associated with the ISDE congress remain useful for understanding how this field evolved.

How Photodynamic Therapy Works

PDT begins with administration of a photosensitiser, followed by a waiting period that allows the agent to accumulate in targeted tissue. An endoscope then delivers light at a specified wavelength. The treatment can destroy areas of dysplasia without removing the entire oesophageal wall, making it less invasive than oesophagectomy for carefully selected cases.

The therapy does not replace precise diagnosis. High-grade dysplasia should be confirmed by experienced gastrointestinal pathologists, while visible nodules or irregular lesions generally require resection for accurate histological assessment. EMR or dissection may therefore come before ablation, especially when an early cancer cannot be excluded.

Where It Fits In Modern Care

PDT has demonstrated that endoscopic eradication can reduce progression from high-grade dysplasia to cancer. Its historical importance is considerable, particularly for patients who were poor surgical candidates or who required an alternative to oesophagectomy. The treatment may still be discussed when standard options are unsuitable, unavailable or clinically inappropriate.

Current practice often favours EMR for visible lesions followed by RFA for residual flat Barrett’s mucosa. PDT can cause deeper and less predictable tissue injury than newer ablation methods, increasing the risk of strictures and healing problems. Selection should therefore be made by an upper gastrointestinal team rather than by a single practitioner working in isolation.

In Australia, such decisions commonly sit within tertiary referral pathways in Sydney, Melbourne, Brisbane, Adelaide and Perth. A patient from regional New South Wales or northern Queensland may need several visits to a metropolitan centre, so travel, accommodation and surveillance schedules belong in the initial discussion.

Benefits And Limitations

A major benefit of PDT is that it can treat a broad field of abnormal mucosa through an endoscopic procedure. It avoids the physiological burden of major surgery and may preserve the oesophageal anatomy. For frail patients, that distinction can be clinically meaningful, provided the treatment goal and expected number of sessions are clear.

Its limitations are equally important. Photosensitivity can persist after treatment, requiring strict protection from bright light for a period determined by the photosensitiser. Chest discomfort, swallowing difficulty, nausea and fever may occur. Oesophageal strictures can develop and sometimes require endoscopic dilation, while incomplete eradication or recurrence means that surveillance remains essential.

The balance can feel especially significant in Australia’s mixed public and private health system. Access to advanced endoscopy, pathology review and repeated procedures may differ between metropolitan hospitals and regional services, and Medicare coverage does not automatically make every component of a complex pathway readily available. Patients should receive a written plan covering costs, travel and follow-up.

Choosing Patients Carefully

PDT is most relevant when high-grade dysplasia has been verified and the disease is suitable for endoscopic management. The team should document the extent of Barrett’s mucosa, the presence of nodularity, previous treatments, reflux control and any suspicion of invasive cancer. Cross-sectional imaging or other staging tests may be required when cancer is a concern.

The treatment conversation should include alternatives: EMR, endoscopic dissection, RFA, cryotherapy and surgery. Severe reflux, an unsuitable oesophageal anatomy, previous radiation, anticoagulation and significant comorbidity may affect the risk profile. Shared decision-making should use plain language—“the go-ahead” should follow a clear explanation of what happens before, during and after treatment.

Clinical Details Worth Recording

• Histology confirmation and expert pathology review
• Visible lesions requiring resection before ablation
• Photosensitivity precautions and medication timing
• A planned schedule for eradication and surveillance

Questions For The Multidisciplinary Team

• Which treatment offers the safest durable eradication?
• Who will manage post-treatment strictures or pain?
• Where will follow-up endoscopy and biopsies occur?
• What travel and out-of-pocket costs should be expected?

Follow-Up And Australian Practice

PDT is not complete when the light treatment ends. Follow-up endoscopy with systematic biopsies is needed to assess eradication, detect buried or recurrent disease and monitor for strictures. Acid suppression, usually with a proton pump inhibitor, supports mucosal healing and reflux control, while lifestyle and medication advice should be tailored to the individual.

The Australian context makes continuity especially important. A patient treated at Royal Prince Alfred, the Royal Melbourne or another high-volume centre may return to a local gastroenterologist for parts of ongoing care, but records and pathology need to move reliably between services. Telehealth can help with review, though it cannot replace endoscopy when dysplasia surveillance is due.

For clinicians reviewing the evidence and historical development of endoscopic therapy, the ISDE 2021 archive provides a useful congress context, including registration information for the virtual World Congress for Esophageal Diseases. Its educational setting reflects the international collaboration required to compare ablation techniques, refine surveillance and improve outcomes.

Photodynamic therapy remains a specialised option rather than the default treatment for every case of high-grade dysplasia. Its value is greatest when patient factors, lesion characteristics and local expertise align. The immediate practical next step is referral to an upper gastrointestinal multidisciplinary team for expert pathology review, staging and a documented comparison of PDT with current endoscopic alternatives.