Photodynamic therapy for dysplastic Barrett esophagus and early esophageal adenocarcinoma

Endoscopic Therapies for Early Stage Esophageal and Gastric Cancers

Early detection of esophageal and gastric cancers offers the possibility of curative treatments with less-invasive interventions than traditional surgical approaches. This review highlights the main endoscopic therapeutic modalities used for early esophageal and gastric malignancies. Endoscopic resection techniques include endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD). EMR is beneficial for smaller, well-defined lesions and involves resecting the superficial layer of the mucosa. In contrast, ESD permits en bloc resection of larger lesions, including those involving the superficial submucosa, offering precise histopathological assessments and reduced recurrence rates. As such, multidisciplinary collaboration is essential to achieve optimal outcomes.

Advancements in photodynamic therapy of esophageal cancer

The poor prognosis of patients with esophageal cancer leads to the constant search for new ways of treatment of this disease. One of the methods used in high-grade dysplasia, superficial invasive carcinoma, and sometimes palliative care is photodynamic therapy (PDT). This method has come a long way from the first experimental studies to registration in the treatment of esophageal cancer and is constantly being improved and refined. This review describes esophageal cancer, current treatment methods, the introduction to PDT, the photosensitizers (PSs) used in esophageal carcinoma PDT, PDT in squamous cell carcinoma (SCC) of the esophagus, and PDT in invasive adenocarcinoma of the esophagus. For this review, research and review articles from PubMed and Web of Science databases were used. The keywords used were "photodynamic therapy in esophageal cancer" in the years 2000-2020. The total number of papers returned was 1,000. After the review was divided into topic blocks and the searched publications were analyzed, 117 articles were selected.

Post-ablation buried neoplasia in Barrett's esophagus

Endoscopic eradication therapy (EET) with maximal acid suppression is the cornerstone for the management of patients with Barrett's esophagus (BE) associated dysplasia. The occurrence of buried dysplastic glands after re-epithelialization of a neo-squamous epithelium is of concern for endoscopists. Here, we present a patient with BE and high-grade dysplasia successfully treated by EET who developed buried dysplastic BE during surveillance. A review of literature on buried dysplasia after successful endoscopic therapy of BE is also discussed.

Recent advances in understanding and preventing oesophageal cancer

Oesophageal cancer is a common cancer that continues to have a poor survival. This is largely in part due to its late diagnosis and early metastatic spread. Currently, screening is limited to patients with multiple risk factors via a relatively invasive technique. However, there is a large proportion of patients diagnosed with oesophageal cancer who have not been screened. This has warranted the development of new screening techniques that could be implemented more widely and lead to earlier identification and subsequently improvements in survival rates. This article also explores progress in the surveillance of Barrett’s oesophagus, a pre-malignant condition for the development of oesophageal adenocarcinoma. In recent years, advances in early endoscopic intervention have meant that more patients are considered at an earlier stage for potentially curative treatment.

Role of endoscopic therapy in early esophageal cancer

Esophageal carcinoma is a highly lethal cancer associated with high morbidity and mortality. Esophageal squamous cell carcinoma and esophageal adenocarcinoma are the two distinct histological types. There has been significant progress in endoscopic diagnosis and treatment of early stages of cancer using resection and ablation techniques, as shown in several trials in the recent past. Earlier detection of esophageal cancer and advances in treatment modalities have lead to improvement in the 5-year survival from 5% to about 20% in the past decade. Endoscopic eradication therapy is the preferred modality of treatment in cancer limited to mucosal layer of the esophagus as there is very low risk of lymph node metastasis, leading to high cure rates, low risk of recurrence and with few adverse effects. The most common adverse events seen are strictures, bleeding and rarely perforation which can be endoscopically managed. In patients with recurrent advanced disease or invasive tumor, esophagectomy with lymph node dissection remains the mainstay of treatment. There is debate on post-endoscopic surveillance with some studies suggesting closer follow up with upper endoscopy every 6 mo for the first 1-2 years and then annually for the 3 years while others recommending the appropriate action only if symptoms or other abnormalities develop. Overall, the field of endoscopic therapy is still evolving and focus should be placed on careful patient selection using a multidisciplinary approach.

Comparison of endoscopic treatment modalities for Barrett's neoplasia

BACKGROUND

There are few data comparing endoscopic treatment outcomes for Barrett's esophagus (BE).

OBJECTIVE

To compare treatment outcomes in BE patients treated with radiofrequency ablation (RFA), RFA after EMR, and porfimer sodium photodynamic therapy (Ps-PDT).

DESIGN

Retrospective, observational study.

SETTING

Single tertiary center between 2001 and 2013.

PATIENTS

A total of 342 BE patients treated with RFA (n = 119), EMR+RFA (n = 98), and Ps-PDT (n = 125).

MAIN OUTCOME MEASUREMENTS

Rates of complete remission of intestinal metaplasia (CRIM), BE recurrence, and adverse events.

RESULTS

Baseline BE high-grade dysplasia (HGD) and adenocarcinoma were more common in the Ps-PDT group (89%) compared with the EMR-RFA (70%) and RFA (37%) groups. At a median follow-up of 14.2 months, 173 patients (50.6%) achieved CRIM. CRIM was significantly more common in Ps-PDT patients compared with RFA (P < .001) and EMR-RFA (P < .001) patients on multivariable analysis. In patients who achieved CRIM, the rates of subsequent BE recurrence were relatively similar among the 3 groups. Although the rates of bleeding were similar, strictures were less common in RFA patients (2.4%) compared with EMR-RFA (13.3%, P = .001) and Ps-PDT (10.4%, P =.043) patients.

CONCLUSION

This study of endoscopic treatment for Barrett's dysplasia and neoplasia found that complete remission was achieved more often and more rapidly after Ps-PDT with similar disease recurrence rates compared with EMR or RFA. Adverse events were more common after EMR and Ps-PDT. Further studies are required to determine which ablation and resection techniques are ideally suited for each BE patient.

Therapeutic endoscopy and endoscopic ultrasound for gastrointestinal malignancies

Gastrointestinal endoscopy and endoscopic ultrasound not only provide strategies to diagnose and stage malignancy, but also to administer palliative and definitive care. Options for anticancer therapy include endoscopic mucosal resection, photodynamic therapy, thermal therapy, self-expanding metal stents and recently, endoscopic ultrasound-guided therapy, such as intratumoral injection. This review summarizes the available endoscopic techniques with a discussion of indications and recent clinical data pertaining to gastrointestinal malignancy. This review will inform the reader of emerging treatment options and stress the importance of incorporating gastroenterologists into the multidisciplinary approach in the management of gastrointestinal cancers.

Photodynamic Therapy for Barrett's Esophagus and Esophageal Carcinoma

This paper reviews the use of photodynamic therapy (PDT) in patients with Barrett's esophagus and esophageal carcinoma. We describe the history of PDT, mechanics, photosensitizers for PDT in patients with esophageal disease. Finally, we discuss its utility and limitations in this setting.

Advances in endoluminal therapy for esophageal cancer

Advances in endoscopic therapy have resulted in dramatic changes in the way early esophageal cancer is managed as well as in the palliation of dysphagia related to advanced esophageal cancer. Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are effective therapies for accurate histopathologic staging and provide a potential for complete cure. Mucosal ablative techniques (radiofrequency ablation and cryotherapy) are effective adjuncts to EMR and ESD and reduce the occurrence of synchronous and metachronous lesions within the Barrett esophagus. The successes of these techniques have made endoscopic therapy the primary means of management of early esophageal cancer.

Development of Brugada syndrome following photodynamic therapy in a patient with cholangiocarcinoma

Brugada syndrome can be unmasked by several conditions including a febrile state, marked leukocytosis, and electrolyte disturbances. Herein, we describe a 62-year-old man with cholangiocarcinoma in the first reported case of Brugada syndrome onset following photodynamic therapy.

Buried metaplasia after endoscopic ablation of Barrett's esophagus: a systematic review

OBJECTIVES

Endoscopic ablation of Barrett's esophagus can bury metaplastic glands under a layer of neosquamous epithelium. To explore the frequency and importance of buried metaplasia, we have conducted a systematic review of reports on endoscopic ablation.

METHODS

We performed computerized and manual searches for articles on the results of photodynamic therapy (PDT) and radiofrequency ablation (RFA) for Barrett's esophagus. We extracted information on the number of patients treated, biopsy protocol, biopsy depth, and frequency of buried metaplasia.

RESULTS

We found 9 articles describing 34 patients with neoplasia appearing in buried metaplasia (31 after PDT). We found five articles describing a baseline prevalence of buried metaplasia (before ablation) ranging from 0% to 28%. In 22 reports on PDT for 953 patients, buried metaplasia was found in 135 (14.2%); in 18 reports on RFA for 1,004 patients, buried metaplasia was found in only 9 (0.9%). A major problem limiting the conclusions that can be drawn from these reports is that they do not describe specifically how frequently biopsy specimens contained sufficient subepithelial lamina propria to be informative for buried metaplasia.

CONCLUSIONS

Endoscopic ablation can bury metaplastic glands with neoplastic potential but, even without ablation, buried metaplasia often is found in areas where Barrett's epithelium abuts squamous epithelium. Buried metaplasia is reported less frequently after RFA than after PDT. However, available reports do not provide crucial information on the adequacy of biopsy specimens and, therefore, the frequency and importance of buried metaplasia after endoscopic ablation remain unclear.

Endoscopic resection techniques and ablative therapies for Barrett’s neoplasia

Esophageal adenocarcinoma is the most rapidly increasing cancer in western countries. High-grade dysplasia (HGD) arising from Barrett’s esophagus (BE) is the most important risk factor for its development, and when it is present the reported incidence is up to 10% per patient-year. Adenocarcinoma in the setting of BE develops through a well known histological sequence, from non-dysplastic Barrett’s to low grade dysplasia and then HGD and cancer. Endoscopic surveillance programs have been established to detect the presence of neoplasia at a potentially curative stage. Newly developed endoscopic treatments have dramatically changed the therapeutic approach of BE. When neoplasia is confined to the mucosal layer the risk for developing lymph node metastasis is negligible and can be successfully eradicated by an endoscopic approach, offering a curative intention treatment with minimal invasiveness. Endoscopic therapies include resection techniques, also known as tissue-acquiring modalities, and ablation therapies or non-tissue acquiring modalities. The aim of endoscopic treatment is to eradicate the whole Barrett’s segment, since the risk of developing synchronous and metachronous lesions due to the persistence of molecular aberrations in the residual epithelium is well established.

Photodynamic therapy

Photodynamic therapy (PDT) is a photochemical process that uses a photosensitizer drug activated by laser light to produce mucosal ablation. Porfimer sodium PDT has proved long-term efficacy and durability in the treatment of Barrett's esophagus and high-grade dysplasia and early esophageal adenocarcinoma. Its use has been limited by serious side effects including prolonged cutaneous photosensitivity and stricture formation. Other photosensitizers with a better safety profile have been used mostly in Europe with limited experience. The future of PDT lies on a better understanding of dosimetry, tissue properties, and host genetic factors.

The safety and effectiveness of endoscopic and non-endoscopic approaches to the management of early esophageal cancer: a systematic review

INTRODUCTION

Traditionally, management of early cancer (stages 0-IIA) has comprised esophagectomy, either alone or in combination with chemotherapy and/or radiotherapy. Recent efforts to improve outcomes and minimize side-effects have focussed on minimally invasive, endoscopic treatments that remove lesions while sparing healthy tissue. This review assesses their safety and efficacy/effectiveness relative to traditional, non-endoscopic treatments for early esophageal cancer.

METHODS

A systematic review of peer-reviewed studies was performed using Cochrane guidelines. Bibliographic databases searched to identify relevant English language studies published in the last 3 years included: PubMed (i.e., MEDLINE and additional sources), EMBASE, CINAHL, The Cochrane Library, the UK Centre for Reviews and Dissemination (NHS EED, DARE and HTA) databases, EconLit and Web of Science. Web sites of professional associations, relevant cancer organizations, clinical practice guidelines, and clinical trials were also searched. Two independent reviewers selected, critically appraised, and extracted information from studies.

RESULTS

The review included 75 studies spanning 3124 patients and 10 forms of treatment. Most studies were of short term duration and non-comparative. Adverse events reported across studies of endoscopic techniques were similar and less significant compared to those in the studies of non-endoscopic techniques. Complete response rates were slightly lower for photodynamic therapy (PDT) relative to the other endoscopic techniques, possibly due to differences in patient populations across studies. No studies compared overall or cause-specific survival in patients who received endoscopic treatments vs. those who received non-endoscopic treatments.

DISCUSSION

Based on findings from this review, there is no single "best practice" approach to the treatment of early esophageal cancer.

Optimal endoluminal treatment of Barrett's esophagus: integrating novel strategies into clinical practice

Endoluminal therapy has become the first-choice treatment over the last 5 years for early Barrett's neoplasia limited to the mucosa. Long-term follow-up data on endoscopic resection have demonstrated the oncological safety of endoscopic resection in comparison to surgery. However, there is a high rate of recurrent disease, which can be avoided using additional ablation of the remaining Barrett. Radiofrequency ablation was recently introduced as an efficacious means to ablate Barrett's epithelium with a better safety profile than older ablation techniques. Recent studies show that endoscopic resection can be safely combined with radiofrequency ablation for treating dysplastic Barrett's after removal of visible lesions. This constitutes a completely new treatment paradigm that will be integrated in routine clinical practice in the forthcoming years.

Prevalence and predictors of recurrent neoplasia after ablation of Barrett's esophagus

BACKGROUND

The incidence and risk factors for recurrence of dysplasia after ablation of Barrett's esophagus (BE) have not been well defined.

OBJECTIVE

To determine the rate and predictors of dysplasia/neoplasia recurrence after photodynamic therapy (PDT) in BE.

SETTING

Retrospective analysis of a prospective cohort of BE patients seen at a specialized BE unit.

METHODS

Patients underwent a standard protocol assessment with esophagogastroduodenoscopy and 4-quadrant biopsies every centimeter at 3-month intervals after ablation. Recurrence was defined as the appearance of any grade of dysplasia or neoplasia after 2 consecutive endoscopies without dysplasia. Entry histology, demographics, length of BE, presence and length of diaphragmatic hernia, EMR, stricture formation, nonsteroidal anti-inflammatory drug use, smoking, and the presence of nondysplastic BE or squamous epithelium were assessed for univariate associations. Time-to-recurrence analysis was done by using Cox proportional hazards regression. A multivariate model was constructed to establish independent associations with recurrence.

RESULTS

A total of 363 patients underwent PDT with or without EMR. Of these, 261 patients were included in the final analysis (44 lost to follow-up, 46 had residual dysplasia, and 12 had no dysplasia at baseline). Indication for ablation was low-grade dysplasia (53 patients, 20%), high-grade dysplasia (152 patients, 58%), and intramucosal cancer (56 patients, 21%). Median follow-up was 36 months (interquartile range 18-79 months). Recurrence occurred in 45 patients. Median time to recurrence was 17 months (interquartile range 8-45 months). Significant predictors of recurrence on the multivariate model were older age (hazard ratio [HR] 1.04, P=.029), presence of residual nondysplastic BE (HR 2.88, P=.012), and a history of smoking (HR 2.68, P=.048).

LIMITATIONS

Possibility of missing prevalent dysplasia despite aggressive surveillance.

CONCLUSION

Recurrence of dysplasia/neoplasia after PDT ablation is associated with advanced age, smoking, and residual BE.

Treatment for Barrett's oesophagus

BACKGROUND

Treatments for Barrett's oesophagus, the precursor lesion of adenocarcinoma, are available but whether these therapies effectively prevent the development of adenocarcinoma, and in some cases eradicate the Barrett's oesophagus segment, remains unclear.

OBJECTIVES

To summarise, quantify and compare the efficacy of pharmacological, surgical and endoscopic treatments for the eradication of dysplastic and non-dysplastic Barrett's oesophagus and prevention of these states from progression to adenocarcinoma.

SEARCH STRATEGY

We searched CENTRAL (The Cochrane Library 2004, issue 4), MEDLINE (1966 to June 2008) and EMBASE (1980 to June 2008).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing medical, endoscopic or non-resectional surgical treatments for Barrett's oesophagus. The primary outcome measures were complete eradication of Barrett's and dysplasia at 12 months, and reduction in the number of patients progressing to cancer at five years or latest time point.

DATA COLLECTION AND ANALYSIS

Three authors independently extracted data and assessed the quality of the trials included in the analysis.

MAIN RESULTS

Sixteen studies, including 1074 patients, were included. The mean number of participants in the studies was small (n = 49; range 8 to 208). Most studies did not report on the primary outcomes. Medical and surgical interventions to reduce symptoms and sequelae of gastro-oesophageal reflux disease (GORD) did not induce significant eradication of Barrett's oesophagus or dysplasia. Endoscopic therapies (photodynamic therapy (PDT with aminolevulinic acid or porfimer sodium), argon plasma coagulation (APC) and radiofrequency ablation (RFA)) all induced regression of Barrett's oesophagus and dysplasia. The data for photodynamic therapy were heterogeneous with a mean eradication rate of 51% for Barrett's oesophagus and between 56% and 100% for dysplasia, depending on the treatment regimens. The variation in photodynamic therapy eradication rates for dysplasia was dependent on the drug, source and dose of light. Radiofrequency ablation resulted in eradication rates of 82% and 94% for Barrett's oesophagus and dysplasia respectively, compared to a sham treatment. Endoscopic treatments were generally well tolerated, however all were associated with some buried glands, particularly following argon plasma coagulation and photodynamic therapy, as well as photosensitivity and strictures induced by porfimer sodium based photodynamic therapy in particular.

AUTHORS' CONCLUSIONS

Despite their failure to eradicate Barrett's oesophagus, the role of medical and surgical interventions to reduce the troubling symptoms and sequelae of GORD is not questioned. Whether therapies for GORD reduce the cancer risk is not yet known. Ablative therapies have an increasing role in the management of dysplasia within Barrett's and current data would favour the use of radiofrequency ablation compared with photodynamic therapy. Radiofrequency ablation has been shown to yield significantly fewer complications than photodynamic therapy and is very efficacious at eradicating both dysplasia and Barrett's itself. However, long-term follow-up data are still needed before radiofrequency ablation can be used in routine clinical care without the need for very careful post-treatment surveillance. More clinical trial data and in particular randomised controlled trials are required to assess whether or not the cancer risk is reduced in routine clinical practice.

The role of photodynamic therapy in the esophagus

Photodynamic therapy (PDT) is a drug and device therapy using photosensitizer drugs activated by laser light for mucosal ablation. Porfimer sodium PDT has been used extensively with proven long-term efficacy and durability for the ablation of Barrett esophagus and high-grade dysplasia. and early esophageal adenocarcinoma. However, continued use is hampered by an associated stricture risk and prolonged photosensitivity (4-6 weeks). Promising single-center European studies using other forms of PDT, such as aminolevulinic acid PDT, have not been replicated elsewhere, limiting the widespread use of other forms of PDT. Future use of PDT in esophageal disease depends on the development of improved dosimetry and patient selection to optimize treatment outcomes, while minimizing adverse events and complications.

Endoluminal therapy for esophageal disease: an introduction

This introductory article summarizes decades of research from many dedicated gastrointestinal endoscopists. It provides a background to Barrett esophagus (BE), exploring the risk of progression to dysplasia and esophageal adenocarcinoma. Two premalignant conditions, BE and colon adenoma, are compared, including their progression to esophageal adenocarcinoma and colon and rectal carcinoma, respectively. A comparison of the risks of surgical treatment and post-surgical complications of these cancers and of the strikingly different paradigms for their prevention is presented. The article concludes with the rationale for endoscopic treatment of Barrett disease.

A cost-utility analysis of ablative therapy for Barrett's esophagus

BACKGROUND & AIMS

Recommendations for patients with Barrett's esophagus (BE) include endoscopic surveillance with esophagectomy for early-stage cancer, although new technologies to ablate dysplasia and metaplasia are available. This study compares the cost utility of ablation with that of endoscopic surveillance strategies.

METHODS

A decision analysis model was created to examine a population of patients with BE (mean age 50), with separate analyses for patients with no dysplasia, low-grade dysplasia (LGD), or high-grade dysplasia (HGD). Strategies compared were no endoscopic surveillance; endoscopic surveillance with ablation for incident dysplasia; immediate ablation followed by endoscopic surveillance in all patients or limited to patients in whom metaplasia persisted; and esophagectomy. Ablation modalities modeled included radiofrequency, argon plasma coagulation, multipolar electrocoagulation, and photodynamic therapy.

RESULTS

Endoscopic ablation for patients with HGD could increase life expectancy by 3 quality-adjusted years at an incremental cost of <$6,000 compared with no intervention. Patients with LGD or no dysplasia can also be optimally managed with ablation, but continued surveillance after eradication of metaplasia is expensive. If ablation permanently eradicates >or=28% of LGD or 40% of nondysplastic metaplasia, ablation would be preferred to surveillance.

CONCLUSIONS

Endoscopic ablation could be the preferred strategy for managing patients with BE with HGD. Ablation might also be preferred in subjects with LGD or no dysplasia, but the cost effectiveness depends on the long-term effectiveness of ablation and whether surveillance endoscopy can be discontinued after successful ablation. As further postablation data become available, the optimal management strategy will be clarified.

Novel endoscopic therapeutic modalities for superficial neoplasms arising in Barrett's esophagus: a primer for surgical pathologists

This review introduces some of the novel endoscopic modalities used for the treatment of superficial neoplasms arising in the setting of Barrett's esophagus, namely endoscopic mucosal resection and photodynamic therapy. We describe the appropriate technical details for pathologists to know to effectively communicate with the gastroenterologists as well as the pitfalls in the evaluation of endoscopic mucosal resection specimens and post photodynamic therapy follow-up biopsies.

Self-expandable metal stents and trans-stent light delivery: are metal stents and photodynamic therapy compatible?

BACKGROUND AND OBJECTIVES

Obstructive non-small cell lung cancer and obstructive esophageal cancer are US FDA approved indications of photodynamic therapy (PDT). The usefulness of PDT for the treatment of cholangiocarcinoma is currently under clinical investigation. Endoscopic stenting for lumen restoration is a common palliative intervention for those indications. It is important to assess whether self-expandable metal stents are compatible with trans-stent PDT light delivery.

STUDY DESIGN/MATERIALS AND METHODS

Direct effects of various components of metal biliary (n = 2), esophageal (n = 2), and bronchial (n = 1) stents on PDT light transmittance and distribution were examined using a point or linear light source (630 or 652 nm diode laser). Resected pig biliary duct and esophageal wall tissues were used to examine the feasibility of PDT light delivery through the fully expanded metal stents.

RESULTS

While using a point light source, the metal components (thread and joint) of the stent could cause a significant shadow effect. The liner material (polytetrafluoroethylene or polyurethane) could cause various degrees of light absorption. When the stent was covered with a thin layer of biliary duct and esophageal tissues containing all wall layers, the shadow effect could be mitigated due to tissue scattering.

CONCLUSIONS

This study clearly demonstrates that it is feasible to combine stenting and PDT for the treatment of luminal lesions. PDT light dose should be adjusted to counteract the reduction of light transmittance caused by the metal and liner materials of stent.

Treatment of Barrett's esophagus with early neoplasia: a comparison of endoscopic therapy and esophagectomy

BACKGROUND

Endoscopic therapies for early neoplasia in Barrett's esophagus may be a viable alternative to esophagectomy.

OBJECTIVE

Our purpose was to compare endoscopic therapy and esophagectomy.

DESIGN

Retrospective review from a single institution.

SETTING

A medium-sized tertiary referral center.

PATIENTS AND INTERVENTIONS

All patients with Barrett's esophagus and dysplasia or intramucosal carcinoma treated by photodynamic therapy (PDT), EMR, or argon plasma coagulation (APC) or esophagectomy with curative intent from May 1998 until November 2005.

MAIN OUTCOME MEASUREMENTS

Survival, progression to cancer, eradication of dysplasia and Barrett's esophagus, major and minor complications, and costs were compared.

RESULTS

Sixty-two patients who underwent endoscopic therapy (2 APC alone, 18 EMR + APC, 20 PDT + APC, and 22 EMR + PDT + APC) and 32 patients who underwent esophagectomy met the inclusion criteria. The 30-day mortality rate included 1 patient in the endotherapy group (2%) and none in the surgical group (P = .49). No deaths from esophageal cancer occurred in either group. Cancer developed in 6% of endotherapy patients and in none in the surgical cohort (P < .05). Major and minor complications occurred in 8% and 31% of endotherapy patients, respectively, and 13% and 63% of surgery patients (P = .50, P < .001). Median cost to date was $40,079 for endotherapy and $66,060 for esophagectomy (P < .001).

LIMITATIONS

Retrospective study, relatively short follow-up, small numbers.

CONCLUSIONS

Both endotherapy and esophagectomy can effectively treat high-grade dysplasia and intramucosal carcinoma associated with Barrett's esophagus. Endotherapy is associated with a higher risk of tumor progression, although this is uncommon. Esophagectomy incurs higher initial costs and results in more frequent minor complications but is usually curative.

The role of surveillance endoscopy and endosonography after endoscopic ablation of high-grade dysplasia and carcinoma of the esophagus

Barrett's esophagus (BE) with high-grade dysplasia (HGD) or early carcinoma treated with surgery or photodynamic therapy (PDT) is at risk of recurrence. The efficacy of endoscopic ultrasound (EUS) for surveillance after PDT is unknown. Our objective was to determine if EUS is superior to esophagogastroduodenoscopy (EGD) and/or CT scan for surveillance of BE neoplasia after PDT. The study was designed as a retrospective review with the setting as a tertiary referral center. Consecutive patients with BE with HGD or carcinoma in situ treated with PDT were followed with EUS, CT scan and EGD with jumbo biopsies every 1 cm at 3, 4, or 6-month intervals. Exclusion criteria was < 6 months of follow up and/or < 2 EUS procedures. Main outcome measurements were residual or recurrent disease discovered by any method. Results showed that 67/97 patients met the inclusion criteria (56 men and 11 women). Median follow-up was 16 months. Recurrent or residual adenocarcinoma (ACA) was detected in four patients during follow-up. EGD with random biopsies or targeted nodule biopsies detected three patients. EUS with endoscopic mucosal resection of the nodule confirmed T1 recurrence in one of these three. In the fourth patient, CT scan revealed perigastric lymphadenopathy and EUS-FNA (fine needle aspiration) confirmed adenocarcinoma. There were two deaths, one related to disease progression and one unrelated. The rate of recurrent/persistent ACA after PDT was 4/67 = 6%. EUS did not detect disease when EGD and CT were normal. Limitations of this study include non-blinding of results and preferential status of non-invasive imaging (CT) over EUS. Our experience suggests that EUS has little role in the surveillance of these patients, unless discrete abnormalities are found on EGD or cross-sectional imaging.

Lack of effect of sex and disease state on the pharmacokinetics of porfimer sodium

BACKGROUND

Porfimer sodium is an agent used for photodynamic therapy (PDT) of cancer and other pre-malignant conditions such as high grade dysplasia in Barrett's oesophagus. Since it is activated by non-thermal red light after a 2-day time interval to allow distribution in the target tissues, its pharmacokinetic properties are relevant to the timing of light treatment and to the period of protection against photosensitivity reactions. With the recent availability of a reliable assay overcoming the limitations of previous assays, two definitive pharmacokinetic studies were undertaken.

OBJECTIVE

To determine if sex or a target disease state (cancer) have an effect on porfimer sodium pharmacokinetic parameters.

METHODS

Twenty-four healthy volunteers (12 men and 12 women) and five male patients with oesophageal cancer undergoing palliative PDT for their obstructive lesions were enrolled. All received an intravenous injection of porfimer sodium (Photofrin) 2 mg/kg over 3-5 minutes and underwent serial blood samplings over 35 days postdose. Porfimer sodium was quantified in serum by a validated spectrofluorometry assay and low-level pre-existing interference was subtracted from postdose concentrations.

RESULTS

The two sexes had comparable maximum serum concentrations with a ratio of 0.95. Women tended to have higher areas under the serum concentration-time curve from time zero to the last sampling time, and from time zero to infinity than men, but the difference did not reach significance (ratios of means of 1.18 and 1.20, respectively). Elimination parameters also showed no sex-related differences with a mean distribution half-life of 9.5 hours, clearance of 0.88 mL/h/kg and a terminal elimination half-life of 415 hours (17.3 days). The sexes only differed significantly for the time to reach maximum serum concentration (means of 1.54 and 0.165 hours, for women and men, respectively; p = 0.0239). This is probably because of the sparse sampling schedule and the plateau behaviour of the initial concentrations. The pharmacokinetic parameters in cancer patients were generally comparable to healthy volunteers. However, the mean terminal elimination half-life was 30% shorter (283 hours or 11.8 days) in cancer patients.

CONCLUSION

Sex does not have an effect on porfimer sodium pharmacokinetics. The presence of advanced oesophageal cancer does not seem to have any influence either. These findings confirm that there is no need for sex-specific label recommendations. Also, the elimination phase of porfimer sodium starting progressively from 24 hours postdose supports the recommended time interval for laser light application, the window for PDT debridement and the skin protection period of at least 30 days.

Endoscopic therapy of dysplasia and early-stage cancers of the esophagus

Endoscopic treatments have become a viable alternative for some patients with early-stage esophageal neoplasia. Although esophagectomy remains the standard of care for high-grade dysplasia and superficial cancers, surgical morbidity and mortality may deter patients who are medically unfit or reluctant to undergo surgery. Photodynamic therapy (PDT) and endoscopic mucosal resection (EMR) are the best-studied nonsurgical approaches at present. PDT has been reported to eradicate high-grade dysplasia (HGD) and early Barrett's cancers at rates ranging from 75% to 100% and 17% to 100%, respectively, and a recent randomized controlled trial confirmed that PDT may prevent progression of HGD to cancer. Complete remission rates greater than 90% have also been reported with EMR and other mucosa-ablating interventions, although recurrence rates necessitate close endoscopic surveillance and retreatment in some patients. In addition to PDT and EMR, several emerging endoscopic treatment options for superficial esophageal neoplasia may provide attractive alternatives to surgery.

Cost-benefit analysis of capsule endoscopy compared with standard upper endoscopy for the detection of Barrett's esophagus

BACKGROUND & AIMS

Esophageal capsule endoscopy (ECE) is a promising new technology for the detection of esophageal pathology. Potential advantages for Barrett's esophagus (BE) screening include ability to return to work as a result of lack of intravenous sedation.

METHODS

We designed a Markov model to compare lifetime costs and life expectancy for a cohort of 50-year old men with chronic GERD for the presence of BE. We compared the base-case strategy of no screening for BE to 2 competing screening strategies: (1) ECE followed by upper endoscopy (EGD) if BE were suspected or if there was poor visualization on the ECE; and (2) standard sedated EGD with biopsy. Cost estimates were obtained from a third-party payer perspective. For each strategy we determined lifetime costs, life-years gained, numbers of esophageal cancers detected, death rates from esophageal cancer, and procedural deaths.

RESULTS

Initial EGD was more expensive but more effective compared with the no screening strategy. Assuming a theoretical cohort of 10,000 patients with GERD, initial EGD cost $1988 and was associated with 18.54 life-years compared with $2392 and 18.36 life-years for the ECE arm and $901 and 18.30 life-years for the no screening arm. The incremental cost-effectiveness ratio of screening with EGD compared with the no screening arm was $4530 per life-year gained. The model was robust to a wide range of sensitivity analyses.

CONCLUSIONS

Initial EGD appears more effective and less costly compared with ECE under base-case conditions for patients with chronic GERD undergoing screening for BE.

Buried Dysplasia and Early Adenocarcinoma Arising in Barrett Esophagus After Porfimer-photodynamic Therapy

The restoration of squamous epithelium after photodynamic therapy (PDT) for Barrett esophagus (BE) and its related neoplasms has been noted. It may result in the development of buried neoplasms and/or BE underneath restored squamous epithelium which maintain their potential for malignant transformation. The purpose of this study was to evaluate the prevalence, endoscopic, and histologic characteristics and also response to further treatment of buried neoplastic epithelium developing after PDT. Fifty-two BE patients with high-grade dysplasia (n=19), intramucosal adenocarcinoma (n=28), and invasive adenocarcinoma (n=5) were treated with porfimer PDT. Buried neoplasms completely covered by squamous epithelium were seen in 1 patient before and in 13 patients after PDT. Their prevalence was 0.6% and 7.4% of pre and post-PDT biopsy levels positive for neoplasia (P=0.001). Buried neoplasms, representing the highest grade of residual neoplasm, were noted in a series of 11 post-PDT endoscopies (7.1% of 155 post-PDT endoscopies with neoplastic diagnoses) of 8 patients. Their occurrence after PDT was neither associated with the length of BE, the diffuseness of neoplasms nor the presence of buried lesions before treatment. There was no prevalent location for these lesions in relation to the original segment of BE, although the majority of both surface and buried neoplasms were found in the prior neoplastic sites. Patients with buried neoplasms responded to further treatment similarly to those with only surface neoplasms (8 of 13 vs. 17 of 24) (P=0.33). In conclusion, buried neoplasms are not uncommon after PDT. Thorough endoscopic surveillance with extensive biopsies, especially of the sites previously positive for neoplasia is important to avoid overlooking buried neoplasms that may progress.

Endoluminal therapy for Barrett's esophagus

This article reviews methods to minimize the complications associated with endoscopic therapy for patients with Barrett's esophagus. To place this discussion in context, the natural history of Barrett's esophagus and the risks associated with progression to dysplasia and invasive carcinoma are reviewed. Operative esophageal resection traditionally is recommended for patients with Barrett's high-grade dysplasia and early carcinoma, and these surgical risks also are reviewed. Finally, all currently approved and commercially available methods for endoscopic ablation and resection of Barrett's disease are categorized according to their application methods of ablation: focal ablation, field ablation, and mucosal resection. The clinical experience with these devices is reviewed with their associated adverse events and complications. Caveats, concerns, and recommendations are discussed to help minimize the complications associated with the use of these important technologies that hold the promise of removing or destroying Barrett's disease to prevent the development of invasive carcinoma.

Endoscopic ablation of intestinal metaplasia containing high-grade dysplasia in esophagectomy patients using a balloon-based ablation system

BACKGROUND

This study aimed to determine the optimal treatment parameters for the ablation of intestinal metaplasia (IM) containing high-grade dysplasia (HGD) using a balloon-based ablation system for patients undergoing esophagectomy.

METHODS

Immediately before esophagectomy, patients underwent ablation of circumferential segments of the esophagus containing IM-HGD using the HALO360 system. The treatment settings were randomized to 10, 12, or 14 J/cm2 for two, three, or four applications. After esophagectomy, multiple sections from ablation zones were microscopically evaluated. Histologic end points included maximum ablation depth (histologic layer) and complete ablation of all IM-HGD (yes/no).

RESULTS

Eight men with a mean age of 57 years (range, 45-71 years) were treated, and 10 treatment zones were created. There were no device-related adverse events. At resection, there was no evidence of a transmural thermal effect. Grossly, ablation zones were clearly demarcated sections of ablated epithelium. The maximum ablation depth was the lamina propria or muscularis mucosae. The highest energy (14 J/cm2, 4 applications) incurred edema in the superficial submucosa, but no submucosa ablation. Complete ablation of IM and HGD occurred in 9 of 10 ablation zones (90%), defined as complete removal of the epithelium with only small foci of "ghost cells" representing nonviable, ablated IM-HGD and demonstrating loss of nuclei and cytoarchitectural derangement. One focal area of viable IM-HGD remained at the margin of one ablation zone (12 J/cm2, 2 applications) because of incomplete overlap.

CONCLUSION

Complete ablation of IM-HGD without ablation of submucosa is possible using the HALO360 system. Ablation depth is dose related and limited to the muscularis mucosae. In one patient, small residual foci of IM-HGD at the edge of the ablation zone were attributable to incomplete overlap, which can be avoided. This study, together with nonesophagectomy IM-HGD trials currently underway, will identify the optimal treatment parameters for IM-HGD patients who would otherwise undergo esophagectomy or photodynamic therapy.

Influence of EAP chemotherapy combined with local radiotherapy on the prognosis and interleukin-2 system of esophageal cancer patients with bone metastasis

AIM: To observe the changes of interleukin-2 (IL-2) system and prognosis of esophageal cancer patients with bone metastasis after EAP chemotherapy combined with local radiotherapy.

METHODS: A total of 66 advanced esophageal cancer patients with bone metastasis were divided into 2 groups. One group received ⁶⁰Co local radiotherapy in combination with the regimen of intravenous chemotherapy at normal dosage of EAP (VP₁₆100 mg/m², topmycine 4 mg/m² and carboplatin 60 mg/m²), and the other group only received intravenous chemotherapy. The levels of IL-2, IL-2 receptor and soluble IL-2 receptor were detected before and after treatment.

RESULTS: The short-term efficacy and 1-year survival rate were significantly higher in the patients with combined treatment than those in the controls (93.93% vs 36.36%, P < 0.01; 90.90% vs 54.54%, P < 0.01). Moreover, the levels of IL-2, IL-2 receptor, soluble IL-2 receptor were also markedly higher in the former (23.6 ± 3.12, 23.1 ± 3.14, 771.4 ± 11.32 ng/L vs 44.1 ± 4.07, 53.2 ± 5.24, 123.2 ± 9.34 ng/L, P < 0.01).

CONCLUSION: Intravenous chemotherapy in combination with radiotherapy can significantly improve the levels of IL-2, IL-2 receptor, and soluble IL-2 receptor as well as the prognosis of esophageal cancer patients with bone metastasis.

Multilayered epithelium may be found in patients with Barrett's epithelium and dysplasia or adenocarcinoma

To determine if multilayered epithelium (MLE) is a useful prognostic indicator for a benign natural history of Barrett's epithelium, we evaluated endoscopic biopsies from patients with Barrett's epithelium without and with dysplasia and/or adenocarcinoma and from non-Barrett's controls for the presence of MLE. MLE was found in 6% of non-Barrett's controls, 30% of Barrett's patients with no dysplasia, and 14% of Barrett's patients with dysplasia and/or adenocarcinoma. MLE was significantly associated with shorter lengths of Barrett's epithelium in both Barrett's groups. Three of 5 photodynamic therapy patients were noted to develop MLE after therapy. MLE may be found in patients with dysplasia and/or adenocarcinoma and after photodynamic therapy; its presence is not useful as a prognostic indicator for a more benign course of Barrett's. This study confirms that MLE is significantly associated with shorter lengths of Barrett's epithelium.

Photodynamic therapy in Barrett's esophagus: results of treatment of 17 patients

BACKGROUND

Barrett's esophagus (BE) with dysplasia may progress to esophageal adenocarcinoma. Photodynamic therapy is a promising treatment for BE.

OBJECTIVE

To determine if photodynamic therapy is an acceptable alternative to esophagectomy in BE patients with high-grade dysplasia or early adenocarcinoma.

METHODS

Seventeen patients were treated with photodynamic therapy for BE and high-grade dysplasia or early esophageal adenocarcinoma. Patients with residual Barrett's epithelium were treated with supplemental argon plasma coagulation or potassium titanyl phosphate laser. Patients underwent follow-up endoscopy three, six, nine and 12 months post-treatment, then every six to 12 months. Mean follow-up was 21 months.

RESULTS

High-grade dysplasia or early adenocarcinoma was completely eliminated in nine of 15 (60%) patients. High-grade dysplasia was downgraded in one patient, persisted in one patient and progressed in four patients. Two patients with early esophageal adenocarcinoma were nonresponders. Complications included stricture, sunburn, urticaria, small pleural effusions, esophageal spasm and transient atrial fibrillation.

CONCLUSIONS

Photodynamic therapy with supplemental ablation is a good, noninvasive therapy for elimination of high-grade dysplasia and early adenocarcinoma in BE. Failure to eliminate dysplastic epithelium occurred in 40% of the patients, thereby necessitating careful follow-up.

Photodynamic therapy for Barrett's esophagus with high-grade dysplasia

This article describes advances in photodynamic therapy for patients with Barrett's esophagus and high-grade dysplasia-an important, minimally invasive treatment option proven to safely and durably ablate Barrett's dysplasia and prevent carcinoma while preserving the gastroesophageal junction.

Mild skin photosensitivity in cancer patients following injection of Photochlor (2-[1-hexyloxyethyl]-2-devinyl pyropheophorbide-a; HPPH) for photodynamic therapy

PURPOSE

To measure skin photosensitivity in cancer patients infused with the new second-generation photodynamic sensitizer Photochlor (2-[1-hexyloxyethyl]-2-devinyl pyropheophorbide-a). A major disadvantage of using the clinically approved photosensitizer Photofrin is potentially prolonged and sometimes severe cutaneous phototoxicity.

PATIENTS AND METHODS

Forty-eight patients enrolled in Phases 1 and 2 clinical trials underwent two or more exposures to four graded doses (44.4, 66.6, 88.8 or 133.2 J/cm2) of artificial solar-spectrum light (SSL) before and after administration of Photochlor at a dose of 2.5, 3, 4, 5 or 6 mg/m2 .

RESULTS

The most severe skin response, experienced by only six of the subjects, was limited to erythema without edema and could only be elicited by exposure to the highest light dose. Conversely, eight subjects had no discernible reaction to SSL at any light dose. For nearly all the patients, the peak skin response was obtained when the interval between sensitizer injection and exposure to SSL was 1 day and, generally, their sensitivity to SSL decreased with increasing sensitizer-light interval. For example, a 2-day sensitizer-SSL interval resulted in less severe reactions than those obtained with the 1-day interval in 79% of the subjects, while 90% of the subjects exposed to SSL 3 days after Photochlor infusion had responses that were less severe than those obtained with either the 1- or 2-day sensitizer-SSL interval.

CONCLUSIONS

Photochlor, at clinically effective antitumor doses, causes only mild skin photosensitivity that declines rapidly over a few days.

Endoscopic therapy for Barrett's esophagus

With the increase in the rate of esophageal adenocarcinoma in the United States and the Western world matched with the high morbidity and mortality of esophagectomy, there is an increasing need for new and effective techniques to treat and prevent esophageal adenocarcinoma. A wide variety of endoscopic mucosal ablative techniques have been developed for early esophageal neoplasia. However, long-term control of neoplasic risk has not been demonstrated. Most studies show that specialized intestinal metaplasia may persist underneath neo-squamous mucosa, posing a risk for subsequent neoplastic progression. In this article we review current published literature on endoscopic therapies for the management of Barrett's esophagus.

Emerging endoscopic techniques in oncology

New techniques have expanded the role of endoscopy in the diagnosis, staging, therapy, and palliation of malignancies. Three major areas of emerging technologies--endoscopic ultrasound (EUS), luminal stent technology, and photodynamic therapy (PDT)--are discussed in this article. Although EUS and PDT have been used for more than two decades, they have only recently emerged as established integral methods in the armamentarium of the gastrointestinal endoscopist.

Endoscopic treatment of high-grade dysplasia and early cancer in Barrett's oesophagus

Barrett's oesophagus is the premalignant precursor of oesophageal adenocarcinoma. Non-dysplastic metaplasia can progress to low-grade dysplasia, high-grade dysplasia, and finally to invasive cancer. Although the frequency of adenocarcinoma in patients with Barrett's oesophagus is low, surveillance is justified because the outcome of adenocarcinoma is poor. Oesophagectomy remains the standard treatment for patients with high-grade dysplasia and superficial carcinoma. However, it has been associated with substantial morbidity and mortality and some patients are judged unfit for surgery. In this review, the present status of less invasive procedures is discussed. Endotherapy preserves the integrity of the oesophagus and allows a better quality of life to patients at low risk of developing lymph-node metastases. Opposition to endoscopic treatment is based mainly on the identification of undetected foci of cancer and high-grade dysplasia in oesophagectomy samples. The current ablative techniques used are photodynamic therapy, argon plasma coagulation, laser treatment, and endoscopic mucosal resection.

EUS in the management of the patient with dysplasia in Barrett's esophagus

Barrett's esophagus is the most important risk factor in the development of adenocarcinoma of the esophagus. Barrett's esophagus is generally regarded as the most significant complication of gastroesophageal reflux disease. Adenocarcinoma occurs more frequently in the setting of high-grade dysplasia. The prognosis of adenocarcinoma of the esophagus is strongly correlated with the stage of disease. The prognosis of late stage disease is extremely poor. Cure may be achieved when disease is found at an early stage. Esophagectomy has been the definitive treatment of limited stage adenocarcinoma of the esophagus. The morbidity and mortality rate for esophagectomy is high. Therefore, alternative endoscopic methods for curative treatments have gained popularity. The two main endoscopic therapies, photodynamic therapy and endoscopic mucosal resection, are both effective when applied to early-stage disease. Traditional evaluation of the patient with Barrett's esophagus with high-grade dysplasia includes esophago-gastro-duodenoscopy (EGD) with biopsy and computed tomography of the chest. Endoscopic ultrasound (EUS) has gained popularity in the evaluation of the patient with Barrett's esophagus and high-grade dysplasia because it is the only imaging technique capable of delineating the separate histologic layers of the gastrointestinal tract. The principal role of EUS in evaluating patients with Barrett's-associated dysplasia is to identify patients who may be candidates for endoscopic ablative (endoscopic mucosal resection, photodynamic therapy) therapies. EUS has been shown to be superior to computed tomography (including high resolution spiral CT) or magnetic resonance imaging for preoperative staging in patients with high-grade dysplasia and carcinoma. This review of the literature summarizes the ability of EUS to evaluate patients with Barrett's esophagus and high-grade dysplasia.

Histopathologic aspects of photodynamic therapy for dysplasia and early adenocarcinoma arising in Barrett's esophagus

The efficacy of photodynamic therapy (PDT) is currently evaluated for the treatment of superficial neoplasms arising in Barrett's esophagus (BE). An accurate assessment of this technique requires the evaluation of biopsies before and after treatment. However, despite the importance of pathology, only a limited number of studies have systematically assessed the mucosal changes after PDT. To evaluate mucosal changes after PDT, and pathologic variables that may impact on the success of this therapy, we analyzed the pre- and post-PDT biopsies of a cohort of patients treated by this modality. Thirty-three patients (mean age, 71 years) with high-grade dysplasia (HGD) and/or intramucosal carcinoma (IMC) arising in BE and followed up after PDT using Porfimer sodium form the basis of this study. In all patients, a review of all pre- and post-PDT biopsies was performed. The variables recorded included the histologic grade and architecture of neoplasms, the distribution of neoplasms, and squamous re-epithelialization. IMC and HGD coexisted in the pre-PDT biopsies of 18 patients (54.5%). IMC and HGD showed a prominent tubular proliferation in 14 patients and displayed a papillary pattern (at least partially) in 19 patients. In post-PDT, patches of specialized columnar epithelium were buried under squamous epithelium in 17 patients (51.5%), and foci of dysplasia/carcinoma covered by squamous epithelium were found in 9 patients (27.3%). HGD and/or IMC were eradicated in 17 patients (eradicated group) and persisted in 16 patients (persistent group). In the persistent group, grade and architecture were unchanged after PDT in 62.5% and 87.5% of patients, respectively. The persistent group was characterized by: 1) a more frequent papillary architecture (P < 0.05), and 2) a diffuse distribution of the neoplasms on pre-PDT biopsies (P = 0.05). Singularly, the persistent neoplastic lesions were observed in the distal esophagus (P < 0.05). A systematic histopathologic evaluation allowed us to draw attention to the fact that distally located and papillary-type neoplasia seem resistant to PDT. The higher than expected incidence of buried residual neoplastic epithelium should also be emphasized since it represents a risk for undetected growth of malignancy.