Photodynamic therapy for early esophageal cancers: light versus surgical might

Photodynamic therapy for esophageal cancer: a useful and realistic option

The use of light therapy for tissue destruction is highly attractive for the endoscopic and minimally invasive therapy of esophageal cancer. Photodynamic therapy (PDT) offers the possibility of palliation of advanced obstructing tumors. However, there are other competing techniques, which can be used to open the esophageal lumen. It has also proved very effective in providing prolonged palliation of patients with advanced irresectable cancer. Completely obstructing tumors, tortuous and long lesions, and tumors near the upper end of the esophagus are particularly suitable for photodynamic therapy. Patients with obstruction to an esophageal prosthesis are also well palliated with PDT. A more interesting and exciting development is its use for the eradication of early asymptomatic mucosal disease. Photodynamic therapy is particularly useful for the eradication of field cancerous change in patients with pre-malignant Barrett's esophagus, or early tumors in patients unfit for radical therapy.

Endoscopic therapy of esophageal cancer

In the management of esophageal cancer, endoscopy has evolved from a tool used to provide biopsy confirmation of suspected tumor to an integral part of the staging and ongoing treatment of patients. Endoscopic ultrasound is currently the most accurate means for T and N staging. Improved endoscopic techniques like dye staining and aggressive biopsy protocols can identify very early stage tumors in high-risk groups and allow curative surgery. Patients with early-stage tumors who are not surgical candidates can also be treated with endoscopic mucosectomy, photodynamic therapy, or Nd:YAG laser and still have a chance of long-term cure. Palliation of advanced tumors remains the major role of endoscopy in patients with esophageal cancer. A variety of techniques have proven effective over the years, including dilatation, laser, and rigid prostheses. Newer developments like bipolar probes, injection therapy, photodynamic therapy, and brachytherapy offer potential applications. The development and continuing improvements in both coated and uncoated expandable metal stents have been perhaps the greatest recent advance in endoscopic palliation of malignant dysphagia and esophagorespiratory fistulas. With the increasing array of endoscopic treatments and palliative techniques, emphasis must be placed on considering functional status; tumor characteristics like stage, location, and shape; patient wishes; and local expertise in tailoring treatment plans for each situation.

Management of dysplasia in the columnar-lined esophagus

The management of patients with high-grade dysplasia in Barrett's esophagus is complex and controversial with regard to electing continued endoscopic biopsy surveillance until an early adenocarcinoma is detected or proceeding with partial esophagogastrectomy. Clinical recommendations to patients for either option should be individualized and based on several parameters reflecting patient and clinician factors. Available data on interpretational variation in the diagnosis of dysplasia; limitation of diagnostic errors with the use of a rigorous, systematic endoscopic biopsy protocol; new information on the apparent benign natural history of high-grade dysplasia in some patients; and the morbidity and mortality of esophageal resection all suggest that recommendation for continued endoscopic biopsy surveillance is an appropriate clinical practice in selected patients. Ongoing research investigations on high-grade dysplasia in Barrett's esophagus aim to reduce the potential for diagnostic errors, simplify cancer surveillance, and develop therapeutic interventions that are safer than but as effective as surgery.

Ablative therapies for the columnar-lined esophagus

Endoscopic ablative therapy could reduce the risk for the development of adenocarcinoma in patients with Barrett's esophagus. Combination therapy, which includes pharmacologic or surgical acid control plus endoscopic mucosal ablation, can reverse Barrett's esophagus that has not been accomplished with prior medical or surgical therapy. Pharmacologic esophageal acid control often takes higher than usual doses of proton pump inhibitor therapy. The preliminary results of endoscopic ablation techniques, including laser, photodynamic therapy, and multipolar electrocoagulation, are reviewed. The goal of ablative therapy is to eliminate all intestinal metaplasia and therefore the risk for the development of adenocarcincoma. Endoscopic ablative therapies need to be validated with larger and longer term trials. Better criteria to estimate the risk for the development of adenocarcinoma are needed to select appropriate candidates for combination therapy.