Photodynamic therapy for obstructing esophageal cancer: light dosimetry and randomized comparison with Nd:YAG laser therapy

Optimal Management of Dysphagia in Patients with Inoperable Esophageal Cancer: Current Perspectives

The majority of patients with esophageal cancer are diagnosed at an advanced, incurable stage. Palliation of symptoms, specifically dysphagia, is a crucial component to improve quality of life and optimize nutritional status. Despite multiple available treatment modalities, there is not one accepted or recommended to be the preferred treatment option. Palliative management is often decided by a multidisciplinary team considering factors including local availability, preference, patient life expectancy, and symptom severity. Systemic therapies such as chemotherapy are the most commonly used palliative modalities. Oncologists are most familiar with radiation for dysphagia palliation, especially for advanced metastatic cancer patients with good performance status. One common approach used by endoscopist is self-expandable metal stents. This is preferred for patients with short-term survival and poor functional status as it provides rapid relief of dysphagia. Cryotherapy is a relatively new endoscopic ablative modality and appears to be a promising option for dysphagia palliation, but more data is needed for wider adoption. This review summarizes the current literature on endoscopic and non-endoscopic treatment options for malignant dysphagia.

Impact of residual air trap in balloon on laser treatment of tubular tissue

OBJECTIVES

Tubular tissue, such as the bile duct and esophagus, often suffers from stenosis due to chronic inflammation or excessive contraction of smooth muscle. Laser treatment using a balloon catheter has been used to treat tubular tissue stenosis by mechanically expanding the tissue and irradiating laser light circumferentially on the tissue lumen. As the balloon is inflated with saline, the residual air in a delivery channel is often accumulated in the inflated balloon. Thus, the air trap may cause physical discontinuities at air-saline interface, leading to unpredictable and nonuniform photothermal interactions. The aim of the current study was to evaluate the optical-thermal effects of the air trap in the balloon on laser treatment of the tubular tissue by means of numerical simulations and experimental validations.

MATERIALS AND METHODS

A balloon-assisted diffusing applicator (BDA) was developed to inflate a balloon and deliver uniform and circumferential laser light. Before the balloon inflation, various numbers of deflations (0, 1, 2, 3, and 4) were applied to estimate the average amount of the air removed from the balloon. Ex vivo experiments using porcine liver duct were conducted with two deflation conditions (D0: no deflation for air trap and D3: three deflations for no air trap). The balloon was horizontally situated during laser irradiation to maintain the air trap at the same position in the balloon by minimizing gravity effect. Upon balloon inflation, 532 nm laser light was delivered through the BDA to the tissue (irradiance = 4 W/cm² ) at 10 W for 45 seconds to assess the optical-thermal effects of the air trap on the ductal tissue.

RESULTS

The size of the air trap was noticeably reduced with the number of deflations. The air trap volume in the balloon decreased to 0.5% of the total balloon volume after D3. Ex vivo results demonstrated that thicker coagulative necrosis (CN) for D0 near the air trap region in the tissue than bottom region that contact with saline, representing an asymmetric profile of CN in the tissue. D0 generated 17% thicker and nonuniform CN (overall CN thickness = 1.4 ± 0.7 mm), compared with D3 with no air trap (overall CN thickness = 1.2 ± 0.2 mm; p < 0.05). A threefold larger eccentricity (E) was found in D0 (49 ± 31%) than D3 (15 ± 13%; p < 0.001).

CONCLUSION

Both numerical simulations and experiments validated the effect of the air trap in a balloon on the distribution of CN in a tubular tissue during BDA-assisted laser treatment. Further in vivo studies will assess the current findings on the air trap for clinical translations of BDA-assisted laser treatment of tubular tissue stenosis.

Photodynamic therapy for middle-advanced stage upper gastrointestinal carcinomas: A systematic review and meta-analysis

AIM

To determine the therapeutic effect of photodynamic therapy (PDT) for middle-advanced stage upper gastrointestinal carcinomas.

METHODS

We searched PubMed, EMBASE, the Cochrane Library, China National Knowledge Infrastructure, China Science and Technology Journal Database, and Wanfang Database from inception to April 2018 for randomized controlled studies. These studies compared PDT with other palliative therapies (radiotherapy, chemotherapy, or Nd:YAG laser) and compared PDT, radiotherapy, or chemotherapy alone with PDT combined with chemotherapy/radiotherapy. In our meta-analysis, both fixed and random effects models were used to estimate the risk ratio (RR) for dichotomous outcomes (the response rate and one-year survival rate).

RESULTS

Ten random controlled clinical studies with 953 patients were included in the analysis. The effective rate for PDT was better than that of radiotherapy or Nd:YAG laser for the treatment of middle-advanced upper gastrointestinal carcinomas [RR = 1.36; 95% confidence interval (CI): 1.13-1.65; P = 0.001]. In addition, PDT combined with chemotherapy had significantly better efficacy and a higher one-year survival rate than PDT or chemotherapy alone (significant remission rate, RR = 1.62; 95%CI: 1.34-1.97; P < 0.00001; one-year survival rate, RR = 1.81; 95%CI: 1.13-2.89; P = 0.01).

CONCLUSION

PDT is a useful method for the treatment of middle-advanced stage upper gastrointestinal carcinomas. PDT combined with chemotherapy or radiotherapy can enhance its efficacy and prolong survival time.

Application of photodynamic therapy in gastrointestinal disorders: an outdated or re-emerging technique?

Photodynamic therapy (PDT) is a promising therapeutic modality that involves the administration of a photosensitizer followed by local illumination with a specific wavelength of light in the presence of oxygen. PDT is minimally invasive, has high selectivity for cancer, and has good patient compliance due to the simplicity of the procedure; therefore, PDT is widely used as a palliative and salvage treatment in patients with various gastrointestinal malignancies. When used as a salvage treatment for locoregional failures after definitive chemoradiotherapy for esophageal cancer, favorable results have been reported. PDT in conjunction with biliary stenting is a promising palliative treatment for unresectable cholangiocarcinoma, and can be used as an advanced diagnostic and therapeutic strategy in peritoneal dissemination of gastric cancer. Recent clinical reports of PDT for treating non-resectable pancreatic cancer also show promising results. To widen the application of PDT, the integration of PDT with molecular imaging and nanotechnology is being extensively studied. Based on these new developments, PDT is likely to re-emerge as a valuable technique in the treatment of diverse gastrointestinal diseases.

Revisiting photodynamic therapy dosimetry: reductionist & surrogate approaches to facilitate clinical success

Photodynamic therapy (PDT) can be a highly complex treatment, with many parameters influencing treatment efficacy. The extent to which dosimetry is used to monitor and standardize treatment delivery varies widely, ranging from measurement of a single surrogate marker to comprehensive approaches that aim to measure or estimate as many relevant parameters as possible. Today, most clinical PDT treatments are still administered with little more than application of a prescribed drug dose and timed light delivery, and thus the role of patient-specific dosimetry has not reached widespread clinical adoption. This disconnect is at least partly due to the inherent conflict between the need to measure and understand multiple parameters in vivo in order to optimize treatment, and the need for expedience in the clinic and in the regulatory and commercialization process. Thus, a methodical approach to selecting primary dosimetry metrics is required at each stage of translation of a treatment procedure, moving from complex measurements to understand PDT mechanisms in pre-clinical and early phase I trials, towards the identification and application of essential dose-limiting and/or surrogate measurements in phase II/III trials. If successful, identifying the essential and/or reliable surrogate dosimetry measurements should help facilitate increased adoption of clinical PDT. In this paper, examples of essential dosimetry points and surrogate dosimetry tools that may be implemented in phase II/III trials are discussed. For example, the treatment efficacy as limited by light penetration in interstitial PDT may be predicted by the amount of contrast uptake in CT, and so this could be utilized as a surrogate dosimetry measurement to prescribe light doses based upon pre-treatment contrast. Success of clinical ALA-based skin lesion treatment is predicted almost uniquely by the explicit or implicit measurements of photosensitizer and photobleaching, yet the individualization of treatment based upon each patients measured bleaching needs to be attempted. In the case of ALA, lack of PpIX is more likely an indicator that alternative PpIX production methods must be implemented. Parsimonious dosimetry, using surrogate measurements that are clinically acceptable, might strategically help to advance PDT in a medical world that is increasingly cost and time sensitive. Careful attention to methodologies that can identify and advance the most critical dosimetric measurements, either direct or surrogate, are needed to ensure successful incorporation of PDT into niche clinical procedures.

Interventions for dysphagia in oesophageal cancer

BACKGROUND

Most patients with oesophageal and gastro-oesophageal carcinoma are diagnosed at an advanced stage and require palliative intervention. Although there are many kinds of interventions, the optimal one for the palliation of dysphagia remains unclear. This review updates the previous version published in 2009.

OBJECTIVES

The aim of this review was to systematically analyse and summarise the efficacy of different interventions used in the palliation of dysphagia in primary oesophageal and gastro-oesophageal carcinoma.

SEARCH METHODS

To find new studies for this updated review, in January 2014 we searched, according to the Cochrane Upper Gastrointestinal and Pancreatic Diseases model, the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), MEDLINE, EMBASE and CINAHL; and major conference proceedings (up to January 2014).

SELECTION CRITERIA

Only randomised controlled trials (RCTs) were included in which patients with inoperable or unresectable primary oesophageal cancer underwent palliative treatment. Different interventions like rigid plastic intubation, self-expanding metallic stent (SEMS) insertion, brachytherapy, external beam radiotherapy, chemotherapy, oesophageal bypass surgery, chemical and thermal ablation therapy, either head-to-head or in combination, were included. The primary outcome was dysphagia improvement. Secondary outcomes included recurrent dysphagia, technical success, procedure related mortality, 30-day mortality, adverse effects and quality of life.

DATA COLLECTION AND ANALYSIS

Data collection and analysis were performed in accordance with the methods of the Cochrane Upper Gastrointestinal and Pancreatic Diseases Review Group.

MAIN RESULTS

We included 3684 patients from 53 studies. SEMS insertion was safer and more effective than plastic tube insertion. Thermal and chemical ablative therapy provided comparable dysphagia palliation but had an increased requirement for re-interventions and for adverse effects. Anti-reflux stents provided comparable dysphagia palliation to conventional metal stents. Some anti-reflux stents might have reduced gastro-oesophageal reflux and complications. Newly-designed double-layered nitinol (Niti-S) stents were preferable due to longer survival time and fewer complications compared to simple Niti-S stents. Brachytherapy might be a suitable alternative to SEMS in providing a survival advantage and possibly a better quality of life, and might provide better results when combined with argon plasma coagulation or external beam radiation therapy.

AUTHORS' CONCLUSIONS

Self-expanding metal stent insertion is safe, effective and quicker in palliating dysphagia compared to other modalities. However, high-dose intraluminal brachytherapy is a suitable alternative and might provide additional survival benefit with a better quality of life. Some anti-reflux stents and newly-designed stents lead to longer survival and fewer complications compared to conventional stents. Combinations of brachytherapy with self-expanding metal stent insertion or radiotherapy are preferable due to the reduced requirement for re-interventions. Rigid plastic tube insertion, dilatation alone or in combination with other modalities, and chemotherapy alone are not recommended for palliation of dysphagia due to a high incidence of delayed complications and recurrent dysphagia.

How are palliative care cancer populations characterized in randomized controlled trials? A literature review

CONTEXT

The difficulties in defining a palliative care patient accentuate the need to provide stringent descriptions of the patient population in palliative care research.

OBJECTIVES

To conduct a systematic literature review with the aim of identifying which key variables have been used to describe adult palliative care cancer populations in randomized controlled trials (RCTs).

METHODS

The data sources used were MEDLINE (1950 to January 25, 2010) and Embase (1980 to January 25, 2010), limited to RCTs in adult cancer patients with incurable disease. Forty-three variables were systematically extracted from the eligible articles.

RESULTS

The review includes 336 articles reporting RCTs in palliative care cancer patients. Age (98%), gender (90%), cancer diagnosis (89%), performance status (45%), and survival (45%) were the most frequently reported variables. A large number of other variables were much less frequently reported.

CONCLUSION

A substantial variation exists in how palliative care cancer populations are described in RCTs. Few variables are consistently registered and reported. There is a clear need to standardize the reporting. The results from this work will serve as the basis for an international Delphi process with the aim of reaching consensus on a minimum set of descriptors to characterize a palliative care cancer population.

Comparison of laser-induced damage with forward-firing and diffusing optical fiber during laser-assisted lipoplasty

BACKGROUND AND OBJECTIVES

Laser-assisted lipoplasty is made possible by using an optical fiber that delivers light endoscopically to subcutaneous fat tissue. Most optical fibers for laser-assisted lipoplasty are designed to be irradiated in a forward direction. In this study, we compared forward-firing fiber and diffusing fiber for use in laser-assisted lipoplasty. The effective parameters of the ablation pattern which resulted from the laser-induced damage are discussed for both systems. In particular, we note the effect resulting from the different beam emission patterns and the contours of laser fluence.

METHODS

We used two different laser delivery systems (a forward-firing fiber and a diffusing fiber) to examine how the beam emission pattern affects the laser-assisted coagulation and damage pattern of in vitro fat tissues. A porcine liver tissue (water-rich tissue) was used as a secondary laser target to investigate how the laser-assisted coagulation pattern depends on both the type of tissue (water-rich and lipid-rich tissue) as well as the delivery system. An evaluation using a digital camera and a thermal camera was conducted for the tissue ablation processes in order to observe the generated heat transfer in fat and liver.

RESULTS

The overall shape of the laser-assisted coagulation zone was different from the beam emission pattern in the case where a forward-firing fiber was used within fat tissue. The center of the laser-affected zone is characterized by the formation of a reservoir of melted fat. In the thermal image analysis, there existed a discrepancy between the temperature distribution of the fat tissue and the liver tissue during the forward-firing fiber irradiation. In the liver tissue ablation process, the temperature distribution during the laser ablation also demonstrated an elongated ellipse that matches well with the laser-induced damage zone. The temperature distribution in fat tissue adhered to a more discoid pattern that corresponded to the laser-induced damage zone.

CONCLUSIONS

Based on our findings, we have proposed mechanisms that can explain the laser-induced damage in both tissues when a forward firing fiber is employed as the delivery system. In the case of fat tissue, the ablation mechanism can be characterized by the reservoir formation of melted lipids while the ablation is characterized as the well-known drilling effect for liver tissue.

Endoscopic management of difficult or recurrent esophageal strictures

Esophageal strictures are a common problem in gastroenterological practice. In general, the management of malignant or benign esophageal strictures is different and requires a different treatment approach. In daily clinical practice, stent placement is a commonly used modality for the palliation of incurable malignant strictures causing dysphagia, whereas, if available, intraluminal brachytherapy can be considered in patients with a good performance status. Recurrent dysphagia frequently occurs in malignant cases. In case of tissue in- or overgrowth, a second stent is placed. If stent migration occurs, the stent can be repositioned or a second (preferably partially covered) stent can be placed. Food obstruction of the stent lumen can be resolved by endoscopic cleansing. The cornerstone of the management of benign strictures is still dilation therapy (Savary-Gilliard bougie or balloon). There are a subgroup of strictures that are refractory or recur and an alternative approach is required. In order to prevent stricture recurrence, steroid injections into the stricture followed by dilation can be considered. In case of anastomotic strictures or Schatzki rings, incisional therapy is a safe method in experienced hands. Temporary stent placement is a third option before considering self-bougienage or surgery as a salvage treatment. In this review, the most frequently used endoscopic treatment modalities for malignant and benign stricture management will be discussed based on the available literature, and some practical information for the management in daily clinical practice will be provided.

Randomized comparison of three palliative regimens including brachytherapy, photodynamic therapy, and APC in patients with malignant dysphagia (CONSORT 1a) (Revised II)

OBJECTIVES

Because most esophageal cancers are diagnosed at an advanced stage, a majority of patients require palliative dysphagia treatment. Dysphagia severity and the need for repeated re-canalization procedures significantly affect patients' quality of life (QoL). The aim of this study was to establish whether combining argon plasma coagulation (APC) of the neoplastic esophageal tissue with another re-canalization method results in a longer dysphagia-free period compared with APC alone.

METHODS

We conducted a randomized trial in 93 patients with malignant dysphagia. Patients were followed until death. We compared three regimens of esophageal re-canalization; APC combined with high dose rate (HDR) brachytherapy, APC combined with photodynamic therapy (PDT), and APC alone. The primary outcome measure was the dysphagia-free period following randomization. Secondary measures were survival, QoL, treatment-associated complications, and treatment tolerance. A per-protocol analysis was carried out.

RESULTS

The time to first dysphagia recurrence was significantly different between each combination treatment group and the control group (overall test: P=0.006; HDR vs. control, log-rank P=0.002, PDT vs. control, log-rank P=0.036), but not different between the combination groups (HDR vs. PDT, log-rank P=0.36). The median time to first dysphagia recurrence was 88, 59, and 35 days in the HDR, PDT, and control groups, respectively. There was no difference in overall survival between the study groups (P=0.27). No deaths, perforations, hemorrhages, or fistula formations were attributed to treatment. The only major complication was fever, occurring in three PDT patients. Minor complications were observed significantly more often in the combination treatment groups and included pain in both groups, transient dysphagia worsening, and skin sensitivity in the PDT group. The QoL 30 days after treatment in the HDR group was significantly better than in the other groups.

CONCLUSIONS

In patients with inoperable esophageal cancer, palliative combination treatment of dysphagia with APC and HDR or PDT was significantly more efficient than APC alone, and was safe and well tolerated. APC combined with HDR resulted in fewer complications and better QoL than APC with PDT or APC alone (CONSORT 1b).

WITHDRAWN: Interventions for dysphagia in oesophageal cancer

BACKGROUND

The majority of oesophageal and gastro-oesophageal cancers are diagnosed at an advanced stage and palliative treatment is the realistic management option for most patients. The optimal intervention for the palliation of dysphagia in these patients has not been established.

OBJECTIVES

To systematically analyse and summarise the efficacy of different interventions used in the palliation of dysphagia in primary oesophageal carcinoma.

SEARCH STRATEGY

We undertook a search according to the Cochrane Upper Gastrointestinal and Pancreatic Diseases model using the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), MEDLINE, EMBASE and CINAHL and major conference proceedings up to August 2005. The literature search was re-run in August 2006 and March 2007.

SELECTION CRITERIA

Randomised controlled trials (RCTs) in patients with inoperable or unresectable primary oesophageal cancer who underwent palliative treatment. We included rigid plastic intubation, self-expanding metallic stent (SEMS) insertion, brachytherapy, external beam radiotherapy, chemotherapy, oesophageal bypass surgery, chemical and thermal ablation therapy, either head-to-head or in combination. The primary outcome was dysphagia improvement. Secondary outcomes included recurrent dysphagia, technical success, procedure related mortality, 30-day mortality, adverse effects and quality of life.

DATA COLLECTION AND ANALYSIS

One author assessed the eligibility criteria of each study and extracted data regarding outcomes and factors affecting risk of bias.

MAIN RESULTS

We included 2542 patients from 40 studies. SEMS insertion is safer and more effective than plastic tube insertion. Thermal and chemical ablative therapy provide comparable dysphagia palliation but have an increased requirement for re-interventions and adverse effects. Anti-reflux stents provide comparable dysphagia palliation to conventional metal stents. Some anti-reflux stents might reduce gastro-oesophageal reflux compared to conventional metal stents. Brachytherapy might be a suitable alternative to SEMS in providing a survival advantage and possibly a better quality of life.

AUTHORS' CONCLUSIONS

Self-expanding metal stent insertion is safe, effective and quicker in palliating dysphagia compared to other modalities. However, high-dose intraluminal brachytherapy is a suitable alternative and might provide additional survival benefit with a better quality of life. Self-expanding metal stent insertion and brachytherapy provide comparable palliation to endoscopic ablative therapy but are preferable due to the reduced requirement for re-interventions. Rigid plastic tube insertion, dilatation alone or in combination with other modalities, chemotherapy alone, combination chemoradiotherapy and bypass surgery are not recommended for palliation of dysphagia due to a high incidence of delayed complications and recurrent dysphagia.

Interventions for dysphagia in oesophageal cancer

BACKGROUND

The majority of oesophageal and gastro-oesophageal cancers are diagnosed at an advanced stage and palliative treatment is the realistic management option for most patients. The optimal intervention for the palliation of dysphagia in these patients has not been established.

OBJECTIVES

To systematically analyse and summarise the efficacy of different interventions used in the palliation of dysphagia in primary oesophageal carcinoma.

SEARCH STRATEGY

We undertook a search according to the Cochrane Upper Gastrointestinal and Pancreatic Diseases model using the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), MEDLINE, EMBASE and CINAHL and major conference proceedings up to August 2005. The literature search was re-run in August 2006 and March 2007.

SELECTION CRITERIA

Randomised controlled trials (RCTs) in patients with inoperable or unresectable primary oesophageal cancer who underwent palliative treatment. We included rigid plastic intubation, self-expanding metallic stent (SEMS) insertion, brachytherapy, external beam radiotherapy, chemotherapy, oesophageal bypass surgery, chemical and thermal ablation therapy, either head-to-head or in combination. The primary outcome was dysphagia improvement. Secondary outcomes included recurrent dysphagia, technical success, procedure related mortality, 30-day mortality, adverse effects and quality of life.

DATA COLLECTION AND ANALYSIS

One author assessed the eligibility criteria of each study and extracted data regarding outcomes and factors affecting risk of bias.

MAIN RESULTS

We included 2542 patients from 40 studies. SEMS insertion is safer and more effective than plastic tube insertion. Thermal and chemical ablative therapy provide comparable dysphagia palliation but have an increased requirement for re-interventions and adverse effects. Anti-reflux stents provide comparable dysphagia palliation to conventional metal stents. Some anti-reflux stents might reduce gastro-oesophageal reflux compared to conventional metal stents. Brachytherapy might be a suitable alternative to SEMS in providing a survival advantage and possibly a better quality of life.

AUTHORS' CONCLUSIONS

Self-expanding metal stent insertion is safe, effective and quicker in palliating dysphagia compared to other modalities. However, high-dose intraluminal brachytherapy is a suitable alternative and might provide additional survival benefit with a better quality of life. Self-expanding metal stent insertion and brachytherapy provide comparable palliation to endoscopic ablative therapy but are preferable due to the reduced requirement for re-interventions. Rigid plastic tube insertion, dilatation alone or in combination with other modalities, chemotherapy alone, combination chemoradiotherapy and bypass surgery are not recommended for palliation of dysphagia due to a high incidence of delayed complications and recurrent dysphagia.

Interventions for dysphagia in oesophageal cancer

BACKGROUND

The majority of oesophageal and gastro-oesophageal cancers are diagnosed at an advanced stage and palliative treatment is the realistic management option for most patients. The optimal intervention for the palliation of dysphagia in these patients has not been established.

OBJECTIVES

To systematically analyse and summarise the efficacy of different interventions used in the palliation of dysphagia in primary oesophageal carcinoma.

SEARCH STRATEGY

We undertook a search according to the Cochrane Upper Gastrointestinal and Pancreatic Diseases model using the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), MEDLINE, EMBASE and CINAHL and major conference proceedings up to August 2005. The literature search was re-run in August 2006 and March 2007.

SELECTION CRITERIA

Randomised controlled trials (RCTs) in patients with inoperable or unresectable primary oesophageal cancer who underwent palliative treatment. We included rigid plastic intubation, self-expanding metallic stent (SEMS) insertion, brachytherapy, external beam radiotherapy, chemotherapy, oesophageal bypass surgery, chemical and thermal ablation therapy, either head-to-head or in combination. The primary outcome was dysphagia improvement. Secondary outcomes included recurrent dysphagia, technical success, procedure related mortality, 30-day mortality, adverse effects and quality of life.

DATA COLLECTION AND ANALYSIS

One author assessed the eligibility criteria of each study and extracted data regarding outcomes and factors affecting risk of bias.

MAIN RESULTS

We included 2542 patients from 40 studies. SEMS insertion is safer and more effective than plastic tube insertion. Thermal and chemical ablative therapy provide comparable dysphagia palliation but have an increased requirement for re-interventions and adverse effects. Anti-reflux stents provide comparable dysphagia palliation to conventional metal stents. Some anti-reflux stents might reduce gastro-oesophageal reflux compared to conventional metal stents. Brachytherapy might be a suitable alternative to SEMS in providing a survival advantage and possibly a better quality of life.

AUTHORS' CONCLUSIONS

Self-expanding metal stent insertion is safe, effective and quicker in palliating dysphagia compared to other modalities. However, high-dose intraluminal brachytherapy is a suitable alternative and might provide additional survival benefit with a better quality of life. Self-expanding metal stent insertion and brachytherapy provide comparable palliation to endoscopic ablative therapy but are preferable due to the reduced requirement for re-interventions. Rigid plastic tube insertion, dilatation alone or in combination with other modalities, chemotherapy alone, combination chemoradiotherapy and bypass surgery are not recommended for palliation of dysphagia due to a high incidence of delayed complications and recurrent dysphagia.

Barrett's esophagus and the increasing role of endoluminal therapy

Barrett's esophagus, or the presence of specialized intestinal mucosa in the esophagus that has a malignant potential, has experienced a rapid increase in diagnosis and prevalence over the past few decades. Once thought to progress to adenocarcinoma in an orderly sequence of increasing dysplasia, recent data suggest the process can be more random. In combination with targeted surveillance endoscopy, recent improvements in technology have aided endoluminal therapy in becoming a cost-effective adjunct to medication. When used in combination, in particular, these ablative therapies have become suitable, if not preferable, alternatives to surgery in many patients.

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.

Measuring Subjective Side Effects and Symptoms in Palliative Photodynamic Therapy

PURPOSE/OBJECTIVES

To evaluate the reliability and validity of the Photodynamic Therapy Side Effects and Symptoms Scale (PSES) and to begin to describe patient-reported outcomes of photodynamic therapy (PDT).

DESIGN

Repeated-measures instrument validation. The PSES uses a 10-point numeric scale to evaluate side effects or symptom trouble or burden on 13 items.

SETTING

A Pacific Northwest community hospital.

SAMPLE

14 patients with end-stage lung or esophageal cancer undergoing palliative PDT.

METHODS

Participants completed five PSES surveys (i.e., at baseline and once a week for four weeks after PDT). Weekly phone calls were made to assess functional status, operationalized as Karnofsky Performance Status.

MAIN RESEARCH VARIABLES

Symptoms and functional status.

FINDINGS

The PSES possessed acceptable internal consistency reliability and concurrent validity. Functional status declined in the first week after PDT, concurrent with an increase in side-effect and symptom burden. Photosensitivity became more burdensome over time but was never extremely burdensome.

CONCLUSIONS

The feasibility of measuring a diverse set of side effects and symptoms in end-stage cancer with a single-page, large-type instrument essentially was supported. The study provided preliminary information about side effects and symptoms in patients undergoing palliative PDT.

IMPLICATIONS FOR NURSING

Nurses often are called on to provide information to patients considering various treatment options. This study offers the first data on patient-reported outcomes of palliative PDT that clinicians can use to help in answering inquiries. The design of the PSES may be replicated by researchers working with other populations with end-stage disease to reduce respondent burden and decrease attrition.

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.

Role of photodynamic therapy in unresectable esophageal and lung cancer

The incidence of esophageal cancer has increased dramatically in the Western population in the last two decades. Many of these patients tend to present late in the disease course with symptoms of dysphagia and malnutrition. Thus a majority of patients at presentation may require palliation of their symptoms. Lung cancer is the most common cause of cancer related mortality in the United States. Similar to esophageal cancer, many patients present in advanced stages where surgical resection for cure may not be an option. Endobronchial obstruction from both primary and metastatic neoplasm causes significant morbidity. The modalities, which are currently available for palliation of symptoms include surgery, photodynamic therapy, dilation, external beam radiation, stents, Nd:YAG laser therapy, and brachytherapy. Each of these modalities has their specific advantages and drawbacks. In this article, we discuss the role of photodynamic therapy in the palliation of esophageal and lung cancer.

Palliative therapy

There are a wide variety of palliative treatments for esophageal cancer. The aim of most treatments is to maintain oral food intake, which should stabilize or even improve quality of life. Stent placement is currently the most widely used treatment modality for palliation of dysphagia from esophageal cancer. Stent placement offers a rapid relief of dysphagia, however, the rate of complications (late hemorrhage) and recurrent dysphagia (stent migration, tumor overgrowth) is relatively high. The scientific evidence to advocate the use of anti-reflux stents for the prevention of gastro-esophageal reflux is currently too low. Photodynamic therapy is mostly used in North America; however, due to the high costs of the treatment, the long-lasting side effects and the necessity of repeated treatments, it is not an ideal treatment for palliation of malignant dysphagia. Nd:YAG laser is a relatively effective and safe treatment modality, although laser treatment is also expensive, technically difficult and requiring repeated treatment sessions at 4-6 weeks intervals. Single dose brachytherapy compares favorably to stent placement in long-term effectiveness and safety. Effective treatment strategies are probably 12 Gy given in one fraction or 16 Gy given in two fractions. Palliative chemotherapy offers response rates in recent trials (including partial and complete responses) ranging from 35% to 50%. Whether palliative chemotherapy also results in a survival benefit is not established yet. For clinical trials on palliation of esophageal cancer, the measurement of quality of life is an important outcome measure. The cancer-specific EORTC QLQ-C30 and the esophageal cancer-specific EORTC-OES-18 are validated measures for establishing quality of life status. For the future, a multimodality approach with stent placement or brachytherapy in combination with chemotherapy may be indicated.

Quality improvement guidelines for placement of esophageal stents

Esophageal cancer is now the sixth leading cause of death from cancer worldwide. During the past three decades, important changes have occurred in the epidemiologic patterns associated with this disease. Due to the distensible characteristics of the esophagus, patients may not recognize any symptoms until 50% of the luminal diameter is compromised, explaining why cancer of the esophagus is generally associated with late presentation and poor prognosis. Esophageal cancer has a poor outcome, with an overall 5 year survival rate of less than 10%, and fewer than 50% of patients are suitable for resection at presentation. As a result palliation is the best option in this group of patients. The aims of palliation are maintenance of oral intake, minimizing hospital stay, relief of pain, elimination of reflux and regurgitation, and prevention of aspiration. For palliative care, current treatment options include thermal ablation, photodynamic therapy, radiotherapy, chemotherapy, chemical injection therapy, argon beam or bipolar electrocoagulation therapy, enteral feeding (nasogastric tube/percutaneous endoscopic gastrostomy), and intubation (self-expanding metal stents (SEMS) or semi-rigid prosthetic tubes) with different success and complications rates.

Esophageal palliation--photodynamic therapy/stents/brachytherapy

The optimal treatment for malignant dysphagia should be safe, effective,cost-effective, and have minimal morbidity. Photodynamic therapy,brachytherapy, and esophageal stenting all represent viable options for the palliation of malignant dysphagia. Characterization of the patients and their tumors allows individualization of the treatment and the selection of the optimal treatment for each individual patient. Institutional resources and expertise also are significant factors in treatment. Further comparative studies may help further delineate the relative merits of these treatments and the optimal treatment of patients with malignant obstruction.

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5-Aminolaevulinic acid compared to polyhematoporphyrin photosensitization for photodynamic therapy of malignant bronchial and esophageal stenosis: clinical experience

BACKGROUND AND OBJECTIVE

Polyhematoporphyrins (PhP) as sensitizers for photodynamic therapy (PDT) in malignant bronchial and esophageal stenosis carry the risk of prolonged photosensitivity of the skin. New line sensitizers such as 5-aminolaevulinic acid (ALA) with low rates of skin phototoxicity appear to be promising alternatives. The aim of this study was to evaluate the efficacy of ALA compared to PhP for PDT regarding phototoxicity of the skin, reduction of tumour stenosis and tumour length and Karnofsky performance status.

PATIENTS AND METHODS

After diagnostic work-up, photosensitization was done in 38 patients with ALA (60mg/kg body weight, oral, 6-8h prior to PDT) and in 51 patients with PhP (2mg/kg body weight, i.v., 48h before PDT). The light dose was calculated as 300J/cm fibre tip. Light at 630nm was applied using a pumped dye laser. In both groups, additional hyperbaric oxygenation was applied at a level of 2 bar absolute pressure.

RESULTS

Improvement regarding stenosis diameter, tumour length and Karnofsky performance status could be obtained in both treatment arms with a significant difference in favour of the PhP-group, P = 0.00073; 0.000014, and 0.00015, respectively. No sunburn or other major treatment related complications occurred in either treatment arms.

CONCLUSION

Photosensitization with PhP compared to ALA seems to be more effective in PDT of malignant bronchial and esophageal stenosis.

Surgical palliation of thoracic malignancies

Primary and metastatic thoracic malignancies are often incurable. Surgeons caring for these patients must be familiar with the options,indications, techniques, and limitations of interventions for palliative treatments in these patients. This article is an overview of the current practices for palliation of a broad spectrum of complaints relating to patients with carcinomas of the lung, esophagus,and mesothelium. The information can be used for treatment of patients with complaints secondary to less common malignancies and metastatic disease of the thorax.

Photodynamic therapy as palliation for esophageal cancer: experience in 215 patients

BACKGROUND

Photodynamic therapy (PDT) utilizes a photosensitizing agent, light, and oxygen to endoscopically ablate cancer cells. This review summarizes our experience with PDT for the palliation of bleeding or obstructing esophageal cancer (EC).

METHODS

All patients with bleeding or obstructing EC treated with PDT from November 1996 through June 2002, were reviewed. After Photofrin II injection, nonthermal light treatment was delivered endoscopically. Dysphagia scores, duration of palliation, reinterventions, complications, and survival after treatment were reviewed.

RESULTS

A total of 215 patients underwent 318 courses of PDT for bleeding (n = 15), obstruction (n = 277), bleeding and obstruction (n = 18), or other indications (n = 8). Tumor histology included 179 adenocarcinomas, 33 squamous cell carcinomas, and 3 undifferentiated. Seventy-five percent of EC were in the distal esophagus. In 85% of courses for obstruction, mean dysphagia scores improved pre- and post-PDT. The mean dysphagia-free interval was 66 days. Supplemental nutrition was discontinued after PDT in 8 of 27 patients (30%). Thirty-five patients required stent placement after PDT with a mean interval to reintervention of 58.5 days. PDT complications included perforation (2% of treatment courses), stricture (2%), Candida esophagitis (2%), pleural effusions (4%), and sunburn (6%). The procedure-related mortality rate was 1.8%, and median survival was 4.8 months.

CONCLUSIONS

PDT offers effective palliation for patients with obstructing EC in 85% of treatment courses. The ideal EC patient for PDT palliation has an obstructing endoluminal cancer. Patients living more than 2 months may require reintervention to maintain palliation of malignant dysphagia, and a multimodality treatment approach is common.

Photodynamic therapy (PDT) in esophageal cancer: a surgical view of its indications based on 14 years experience

The aim of this paper is to present the updated experience of the Yorkshire Laser Centre in PDT for esophageal cancer and to identify its role in specific subsets of patients. Also, in the light of this experience, to compare and contrast the results of PDT with appropriate subsets of patients treated in my esophageal surgery practice. 102 consecutive patients; 84 with advanced (Group A) and 18 with early (Group E) stage esophageal cancer undergoing endoscopic PDT were entered into a prospective study. Every patient had standard work up including clinical staging. PDT protocol was intravenous administration of Photofrin 2mg/kg body weight followed 24-72 hours later by endoscopic illumination using 630 nm laser light. Assessment of results was made on the basis of mortality, morbidity, patient satisfaction to treatment, symptom relief and survival. For comparison of PDT role with non PDT treated patients, reference is made to 3 previous publications comprising over 1100 patients [Moghissi, K., Br. J. Surg. 79, 935-937 (1992) (ref. 1); Sawant, D., Moghissi, K. Eur. J. Cardio-Thorac. Surg. 8, 113-117 (1994) (ref. 2); Sharpe, D. A. C., Moghissi, K. Eur. J. Cardiothorac. Surg. 10, 359-364 (1996) (ref. 3)]. There was no mortality associated with PDT. All patients expressed satisfaction to treatment. Post PDT complications consisted of photosensitivity skin reaction (sunburn) in 5 patients (5%) and esophageal stricture in 8 (8%) patients. Group A: There was significant symptom and dysphagia grade improvement. Mean survival was 9.5 months. Group E: There were no significant symptoms pre or post PDT and mean survival was 60.5 months. Comparison of PDT results in Group A with results of other palliative treatment methods, indicates that palliation can be achieved in all intraluminal cancer using PDT which is at least as good as other treatments. There is, in addition, advantage over other methods in patients with cervical esophageal cancer and in cases with re-growth of tumor obstructing previously placed stents. In early cases PDT appears capable of replicating surgical results in selected cases. PDT is an effective and safe treatment method in esophageal cancer. In advance disease it improves swallowing. In early stage disease it offers long survival and the prospect of cure in some patients. At present the role of PDT in early stage cancer should be limited to patients who are unsuitable for surgical resection. Therefore, PDT should be considered as a valid oncological option to be applied in selected cases.

Mucosal ablation with photodynamic therapy in the esophagus: optimization of light dosimetry in the sheep model

BACKGROUND

Photodynamic therapy is an attractive technique for mucosal ablation in patients with superficial squamous cell carcinoma of the esophagus, or high-grade dysplasia or early stage adenocarcinoma arising in Barrett's esophagus. Although illumination with green light is assumed to be safe, choice of the light has been empirical in clinical studies; light dose is often reduced to avoid potential complications. The present study assessed the safety of green and blue lights during photodynamic therapy in the esophagus by progressively administrating increasing doses in an attempt to standardize the dose and determine a safe upper limit. This would considerably simplify photodynamic therapy and improve therapeutic results.

METHODS

The sheep model was chosen because of similarities with humans regarding the thickness and histologic structure of the esophagus. Irradiation with a 180 degrees windowed cylindrical light distributor was performed in 19 sheep 4 days after injection of 0.15 mg/kg of tetra(m-hydroxyphenyl) chlorin. Light doses ranged from 10 to 500 J/cm(2) at 514 nm (argon ion laser) and from 5 to 250 J/cm(2) at 413 nm (krypton laser).

RESULTS

Follow-up endoscopies revealed a tissue response with a fibrinous area at almost all light doses, whereas application of extremely high light doses tended to induce circumferential necrosis with subsequent stenosis. Three months after irradiation with green light, histologic examination of the resected specimens revealed transmural scarring at doses higher than 100 J/cm(2). After illumination with blue light, partial or more extensive fibrosis of the muscular layer was observed only at light doses of 175 to 250 J/cm(2).

CONCLUSIONS

Application of high doses of green light after sensitization with tetra(m-hydroxyphenyl) chlorin led to severe complications in the esophagus of the sheep that are highly likely to occur in humans as well. Blue light causes significantly less damage than green light and may, therefore, be considered as an alternative for photodynamic therapy of early stage superficial esophageal cancer.

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.

Fluorescence endoscopy and photodynamic therapy

Fluorescence endoscopy is a new technique which allows a better detection of non-visible malignant or premalignant lesions or, those which are difficult to detect. Exogenously applied sensitisers accumulate selectively in malignant lesions and induce fluorescence after illumination with light of adequate wavelength. However, also endogenous fluorophores, different located in malignant or benign lesions, induce a different autofluorescence in these lesions. Tissue fluorescence can be detected by optical sampling of the mucosa using fluorescence spectroscopy or by generating real time fluorescence images with specialised camera systems. Compared to point fluorescence spectroscopy the latter technique enables the screening of large surface areas of mucosa. Meanwhile, fluorescence endoscopy is a widely used technique in urology employing 5-aminolaevulinic acid sensitisation. In gastroenterology, this technique seems promising for the detection of early cancers or dysplasia in patients with Barrett's oesophagus or ulcerative colitis. Using different sensitisers, photodynamic therapy seems to be a promising option for patients with advanced oesophageal cancer and in the palliative treatment of non-resectable bile duct cancer, furthermore for patients with early gastric cancer and dysplasia in Barrett's oesophagus. Probably, by laser light fractionation or a combination of different sensitisers, an enhanced effect can be expected.

Methods of palliation of esophageal and gastric cancer

Esophageal and gastric malignancies are common worldwide. Less than half are amenable to curative treatment at the time of diagnosis because of advanced or metastatic disease. Palliation is often required for symptoms, such as dysphagia, gastrointestinal bleeding, aspiration caused by tracheoesophageal fistula, nausea and emesis secondary to gastric outlet obstruction, and malnutrition. This article reviews the gastric outlet obstruction, and malnutrition. This article reviews the medical, endoscopic, and surgical options for palliative treatment.

Monitoring photoproduct formation and photobleaching by fluorescence spectroscopy has the potential to improve PDT dosimetry with a verteporfin-like photosensitizer

In current clinical practice, photodynamic therapy (PDT) is carried out with prescribed drug doses and light doses as well as fixed drug-light intervals and illumination fluence rates. This approach can result in undesirable treatment outcomes of either overtreatment or undertreatment because of biological variations between different lesions and patients. In this study, we explore the possibility of improving PDT dosimetry by monitoring drug photobleaching and photoproduct formation. The study involved 60 mice receiving the same drug dose of a novel verteporfin-like photosensitizer, QLT0074, at 0.3 mg/kg body weight, followed by different light doses of 5, 10, 20, 30, 40 or 50 J/cm2 at 686 nm and a fluence rate of 70 mW/cm2. Photobleaching and photoproduct formation were measured simultaneously, using fluorescence spectroscopy. A ratio technique for data processing was introduced to reliably detect the photoproduct formed by PDT on mouse skin in vivo. The study showed that the QLT0074 photoproduct is stable and can be reliably quantified. Three new parameters, photoproduct score (PPS), photobleaching score (PBS) and percentage photobleaching score (PBS%), were introduced and tested together with the conventional dosimetry parameter, light dose, for performance on predicting PDT-induced outcome, skin necrosis. The statistical analysis of experimental results was performed with an ordinal logistic regression model. We demonstrated that both PPS and PBS improved the prediction of skin necrosis dramatically compared to light dose. PPS was identified as the best single parameter for predicting the PDT outcome.