[Chromoendoscopy, magnification endoscopy, optic biopsy; showmanship or actual improvement?].
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Coloring Agents↗
Biomedical subjects
L Gossner
Publications and source records attributed to L Gossner.
Management of Barrett's oesophagus, dysplasia and early adenocarcinoma.
There has been a dramatic increase in recent years in the incidence of Barrett's oesophagus and the oesophageal adenocarcinoma associated with it. Adequate monitoring strategies and improved diagnostic procedures are therefore essential. Alongside conventional video-endoscopy with four-quadrant biopsies, many additional diagnostic procedures are now available to improve monitoring. These allow the early diagnosis of dysplastic areas and early carcinomas. Both thermal procedures (argon plasma coagulation, multipolar electrocoagulation and KTP laser and Nd∶YAG laser treatment) and non-thermal ablation procedures (photodynamic therapy) are used for the endoscopic ablation of Barrett's mucosa without dysplasia, being employed in addition to acid suppression treatment. On the basis of the data currently available, it is, however, not yet possible to offer a general recommendation in favour of endoscopic ablation. Alongside surgical treatment for high-grade dysplasia and early carcinoma, endoscopic treatment procedures, which have a much lower complication and mortality rate, will probably play an important role in the future. Endoscopic mucosal resection and photodynamic therapy are particularly promising. Long-term results with these procedures are, however, still awaited.
Adenocarcinoma↗
Early stage adenocarcinoma of the esophagus arising in circular heterotopic gastric mucosa treated by endoscopic mucosal resection.
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Adenocarcinoma↗
Photodynamic therapy.
Photodynamic therapy (PDT) is a treatment modality that utilizes a photosensitizing drug activated by laser-generated light and is proving effective for oncologic and nononcologic applications in the gastrointestinal tract. This article provides an overview of the most frequently used photosensitizers and clinical PDT studies in the upper gastrointestinal tract. In the future, the best indications for PDT in the esophagus will not comprise the palliative treatment of obstructing tumors but precancerous lesions such as Barrett's esophagus with or without dysplasia and early cancer. PDT might establish itself as a minimally invasive treatment alternative compared with surgery for high-grade dysplasia or early mucosal cancer of the esophagus.
Esophageal Neoplasms↗
Endoscopic mucosal resection of early cancer and high-grade dysplasia in Barrett's esophagus.
BACKGROUND & AIMS: In view of the mortality and morbidity rates of esophagectomy and the relatively large group of inoperable patients, local therapeutic techniques are required for high-grade dysplasia and early Barrett's cancer. METHODS: A prospective investigation of endoscopic mucosal resection was conducted in 64 patients (mean age, 65 +/- 10 years) who had early carcinoma (61 patients) or high-grade dysplasia (3 patients) in Barrett's esophagus. Thirty-five patients met the criteria for low risk: macroscopic types I, IIa, IIb, and IIc; lesion diameter up to 20 mm; mucosal lesion; and histological grades G1 and G2 and/or high-grade dysplasia (group A). The remaining 29 patients were included in group B (high risk). RESULTS: A total of 120 resections were performed, with no technical problems encountered. The mean number of treatment sessions per patient was 1. 3 +/- 0.6 in group A and 2.8 +/- 2.0 in group B (P < 0.0005). Only one major complication occurred, a case of spurting bleeding, which was managed endoscopically. Complete local remission was achieved significantly earlier (P = 0.008) in group A than in group B. In May 1999, complete remission had been achieved in 97% of the patients in group A and in 59% of those in group B; however, 1 patient in group A and 9 in group B are still undergoing treatment or awaiting the first check-up. During a mean follow-up of 12 +/- 8 months, recurrent or metachronous carcinomas were found in 14%. CONCLUSIONS: Endoscopic mucosal resection of early carcinoma in Barrett's esophagus is associated with promisingly low morbidity and mortality rates. The procedure may offer a new minimally invasive therapeutic alternative to esophagectomy, especially in low-risk situations. Comparisons with surgical results will need to be done when the long-term results of this procedure become available.
Adult↗
Photodynamic therapy of gastric cancer.
Photodynamic therapy is a fascinating concept that will continue to occupy many research groups around the world in coming years. Although a widespread clinical application for the method has not yet emerged, there are good prospects that photodynamic therapy will establish itself at major gastroenterologic centers as an endoscopic procedure with few or no side effects in the treatment of Barrett's esophagus (sever dysplasia and early carcinoma) and, in selected cases, for the treatment of early gastric carcinoma.
Drug Administration Routes↗
Photodynamic destruction of high grade dysplasia and early carcinoma of the esophagus after the oral administration of 5-aminolevulinic acid.
BACKGROUND: Photodynamic therapy (PDT) is a new local, endoscopically controlled therapeutic concept based on the selective sensitization of malignant and precancerous lesions prior to light-induced tissue destruction. 5-aminolevulinic acid (5-ALA) appears to be a promising alternative photosensitizer with a high mucosa specificity without phototoxic side effects on the skin. The authors report on their experiences with this new form of PDT in 27 patients. METHODS: Twenty-seven patients (6 females and 21 males; ages 47-79 years) with histologically proven high grade dysplasia (n = 9) and early carcinoma (normal endoultrasonography or classified as uT1N0M0; n = 19; 1 patient had 2 lesions) of the esophagus were included in this study. Approximately 4-6 hours after oral ingestion of 5-ALA in a dosage of 60 mg/kg of body weight, laser light irradiation was conducted with a dye laser system with a wavelength of 635 nanometers at a light dose of 150 J/cm(2). RESULTS: The length of the segment of the esophagus with severe dysplasia or carcinoma of the mucosa varied between 0.5-9.0 cm (mean length, 2.5 cm). High grade dysplasia was eradicated in all patients. In addition, 19 mucosal tumors in 18 patients were treated successfully in 10 of 19 cases with an average of 1.7 treatment sessions and a mean follow-up of 16.9 months (range, 3-37 months). Method-related morbidity and mortality were not observed. CONCLUSIONS: Severe dysplasia and superficial (</=2 mm) mucosal carcinoma of the esophagus can be ablated completely by 5-ALA-PDT. PDT with 5-ALA has few side effects and might offer an alternative to esophagectomy or radiochemotherapy.
Aged↗
Extraction of migrated self-expanding esophageal metal stents.
BACKGROUND: When self-expanding metal stents are used in the palliative treatment of malignant stenoses complications can occur and require the endoscopic extraction of the stent. METHODS: Three Gianturco-Z stents and two EsophaCoil stents had to be extracted because of migration (4 patients) and strangulation of healthy esophageal tissue between the coil loops during EsophaCoil stent release (1 patient). Because of the strong expansion force of the Gianturco-Z stent, the plastic sheath of a polypectomy snare was replaced by the steel sheath of a basket used for mechanical lithotripsy of bile duct stones. The sufficient resistance of the steel sheath allowed the stents to be compressed. The EsophaCoil stents were gradually retracted with a polypectomy snare over a plastic tube. RESULTS: All stents could be extracted successfully. There were no severe complications related to extraction. CONCLUSION: By means of the endoscopic extraction techniques described above, it is possible to safely remove self-expanding esophageal stents.
Aged↗
KTP laser destruction of dysplasia and early cancer in columnar-lined Barrett's esophagus.
BACKGROUND: The rising incidence of esophageal adenocarcinoma in western countries requires a new strategy in the management of dysplasia in Barrett's esophagus. Esophagectomy, which has high morbidity and mortality rates, has been recommended to treat patients with severe dysplasia. Strictly superficial laser coagulation with tissue ablation therefore is a desirable option for the management of dysplasia in Barrett's esophagus because the tissue to be ablated is only about 2 mm thick. Potassium-titanyl-phosphate (KTP) laser light with a wavelength of 532 nm is preferentially absorbed by hemoglobin and therefore combines excellent coagulation with limited tissue penetration. We report first clinical results with KTP laser superficial vaporization of dysplasia and early cancer in Barrett's esophagus. METHODS: Eight men and 2 women 43 to 84 years of age with short segments of Barrett's esophagus or traditional Barrett's esophagus and histologically proved low-grade (n = 4) and high-grade (n = 4) dysplasia or early adenocarcinoma (n = 2) were selected for this pilot study. For all patients thermal endoscopic destruction was conducted with a frequency-doubled neodymium:yttrium-aluminum-garnet (Nd:YAG) KTP laser system. Laser therapy was performed by means of the free-beam method with coaxial insufflation of gas. An average of 2.4 sessions per patient were required for ablation of the Barrett's mucosa. RESULTS: Two to three days after laser treatment the response of the ablated mucosa was assessed with endoscopy and biopsy. Samples taken showed fibrinoid necrosis of the mucosal layer. A complete response was obtained for all 10 patients. Replacement by normal squamous cell epithelium was induced in combination with acid suppression therapy of up to 80 mg omeprazole daily. No complications occurred. In two patients biopsy showed specialized mucosa beneath the restored squamous cell epithelial layer. Follow-up times were as long as 15 months (mean value 10.6 months). CONCLUSIONS: KTP laser destruction of Barrett's esophagus induced mucosal regeneration with normal squamous cell epithelium in combination with acid suppression. Limitation of the depth of thermal destruction in Barrett's esophagus minimizes risk for perforation or stricture formation. KTP laser ablation of Barrett's esophagus seems to be feasible and safe in short segments of Barrett's esophagus with dysplasia or early cancer.
Adenocarcinoma↗
Antibiotic prophylaxis in percutaneous endoscopic gastrostomy (PEG): a prospective randomized clinical trial.
BACKGROUND AND STUDY AIMS: The most frequent complication reported for percutaneous endoscopic gastrostomy (PEG) is peristomal wound infection which occurs in as many as 30 % of patients. In the studies published so far, the question of whether antibiotic prophylaxis reduces the incidence of peristomal wound infection has remained controversial. We therefore conducted a prospective, randomized trial to determine whether antibiotic prophylaxis can reduce the incidence of peristomal wound infection associated with PEG. PATIENTS AND METHODS: During a 2-year-period a total of 347 patients (251 men, 96 women; mean age 60.2+/-5) were included in our study. In all cases, a 9-French gauge Freka gastrostomy tube was inserted using the "pull" technique. The patients were randomly assigned to three different treatment groups (group 1, antibiotic prophylaxis with 2 g cefotaxime; group 2, antibiotic prophylaxis with 4g piperacillin plus 0.5g tazobactam; group 3, no antibiotic prophylaxis). For a period of one week after gastrostomy, the peristomal area was evaluated using a wound score. According to the score, peristomal infections were classified as being of degree I-IV. Infections of up to degree III were regarded as minor, while an infection of degree IV was defined as a severe complication. RESULTS: PEG tubes were successfully placed in 336/347 patients (97 %). Of the 336 patients, 29 were excluded because of incomplete follow up (dropout rate 9%). Cases included were: in group 1, n = 101; in group 2, n = 100, and in group 3, n = 106. There was no mortality related to PEG insertion. There were five instances of severe complications (1.6%). Patients who received antibiotic prophylaxis had mean daily combined wound scores that were significantly lower than those of patients without antibiotic prophylaxis (P < 0.01). The control group (no antibiotic prophylaxis) exhibited significantly more peristomal wound infections of degree III (n = 8) than antibiotic prophylaxis group 1 (n = 0, P < 0.001) or antibiotic prophylaxis group 2 (n = 1, P < 0.012). Three patients in group 3 (no antibiotic prophylaxis) and one patient in group 2 developed peritonitis. CONCLUSIONS: Severe wound infections requiring medical or endoscopic intervention are very rare events after PEG insertion. Antibiotic prophylaxis significantly reduces the risk of peristomal wound infection associated with PEG insertion. Antibiotic prophylaxis, therefore, is to be recommended as a general measure in percutaneous endoscopic gastrostomy.
Antibiotic Prophylaxis↗
A new long-range through-the-scope balloon applicator for photodynamic therapy in the esophagus and cardia.
BACKGROUND AND STUDY AIMS: Photodynamic therapy (PDT) is a new local, endoscopically controlled therapeutic technique based on the sensitization of malignant and precancerous lesions prior to light-induced tissue destruction. PDT of Barrett's esophagus with severe dysplasia, or of mucosal carcinomas and superficial squamous-cell cancer of the esophagus, requires light application devices allowing homogeneous illumination of the tissue surface in spite of esophageal motility and respiratory movement. On the basis of a commercially available through-the-scope balloon system, we developed a long-range light applicator for homogeneous and circumferential irradiation during PDT, and describe here the initial clinical experience with the device. PATIENTS AND METHODS: The new balloon applicator consists of a flexible cylindrical diffuser fiber with a length of up to 10 cm, depending on the lesion to be illuminated, and an inflatable balloon based on the type of balloon used for esophageal dilation. The balloon is made of a transparent polyurethane membrane with negligible absorption (<5%) at lambda = 600-700 nm, and it can be positioned through the biopsy channel of a conventional endoscope, with direct endoscopic visualization of the targeted lesion. The light intensity distribution perpendicular to the optical axes of the diffuser was measured for red laser light (lambda = 632.8 nm) and for green laser light (lambda = 542 nm). The study of photodynamic treatment included two women and four men (aged 48-79 years) with histologically proved high-grade dysplasia (n = 2) or mucosal cancer in Barrett's esophagus (n = 2) and superficial squamous-cell cancer (SCC) (n = 2), who had undergone EUS staging showing uT0 or uT1N0. Laser light irradiation was conducted after oral ingestion of 5-aminolevulinic acid (5-ALA) or intravenous administration of meta-(tetrahydroxyphenyl)chlorin (mTHPC). RESULTS: Both in vitro and in vivo, precise positioning of the new application system at the targeted tissue and homogeneous illumination were feasible, safe and effective. The total efficiency of transmitted light at wavelengths of lambda = 632.8 nm and lambda = 542 nm was 85-90%. A high degree of homogeneity was measured with applicator lengths of between 15 mm and 95 mm, and the maximum deviation from the mean intensity extended over a range of 40% over the total length of 80 mm. High-grade dysplasia was eradicated in all patients, and in addition mucosal cancer was successfully destroyed in three-quarters of them, requiring an average of 1.3 treatment sessions, with a mean follow-up of 12 months (range 10-15 months). CONCLUSIONS: This centering balloon system may in the future be capable of improving light application techniques during esophageal photodynamic therapy, making PDT a more reliable alternative modality for minimally invasive treatment of high-grade dysplasia and early Barrett's esophagus or squamous-cell carcinoma, as compared with esophagectomy.
Adenocarcinoma↗
Local treatment of early cancer in short Barrett's esophagus by means of argon plasma coagulation: initial experience.
In recent years endoscopically controlled local therapeutic methods, such as photodynamic therapy, mucosectomy, or laser therapy, have been used with a curative aim for the destruction of early esophageal or gastric cancers. We report on our experience of treating histologically proven mucosal cancer in Barrett's esophagus with argon plasma coagulation (APC), in three patients. All the mucosal esophageal cancers, with a mean diameter of 4 mm, were successfully destroyed after one or two treatment sessions. Additionally, in two of the three patients the specialized columnar epithelium was replaced by normal squamous cell epithelium when APC treatment was combined with omeprazole. In the third patient with Barrett's esophagus, a partial squamous cell re-epithelialization was induced. No method-related mortality and morbidity were observed. During the mean follow-up of 24.3 +/- 1.1 months (range 23-25 months) one tumor recurrence developed which was successfully treated with photodynamic therapy. In patients with small early Barrett's carcinoma APC might offer an effective, minimally invasive alternative to mucosectomy or photodynamic therapy, as the treatment procedure is less cumbersome and the equipment less expensive.
Adenocarcinoma↗
Photodynamic ablation of high-grade dysplasia and early cancer in Barrett's esophagus by means of 5-aminolevulinic acid.
BACKGROUND & AIMS: The first therapeutic experiences with the conventional photosensitizer dihematoporphyrinester in the treatment of Barrett's esophagus show the curative potential of photodynamic therapy (PDT). The aim of this study was to test 5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX, a photosensitizer with a high mucosa specificity without phototoxic side effects on the skin, as a new form of PDT. METHODS: Thirty-two patients (mean age, 68.5 years) with histologically proven high-grade dysplasia (n = 10) and mucosal cancer (n = 22) in Barrett's esophagus were treated. Four to 6 hours after oral ingestion of 5-ALA (dose, 60 mg/kg body wt), irradiation was conducted with a dye laser system (635 nm) with a light dose of 150 J/cm2. The patients received 20-80 mg omeprazole daily after PDT. RESULTS: High-grade dysplasia was eradicated in all patients (10 of 10), and mucosal cancer was eliminated in 17 of 22 patients (77%) at a mean follow-up of 9.9 months (range, 1-30 months). All tumors < or = 2 mm in thickness were completely ablated (17 of 17). The method-related mortality and morbidity was 0%. CONCLUSIONS: Severe dysplasia and thin (< or = 2 mm) mucosal cancer of Barrett's esophagus can be completely ablated. PDT might offer a minimally invasive treatment modality as an alternative to esophagectomy.
Adult↗
Photodynamic ablation of early cancers of the stomach by means of mTHPC and laser irradiation: preliminary clinical experience.
BACKGROUND: Radical surgical treatment has been the first choice for early gastric cancer, but high resolution endosonography allows in situ diagnosis with a high sensitivity and specificity and in consequence the option of local endoscopic treatment. AIMS: To evaluate photodynamic therapy (PDT) using meso-tetrahydroxyphenyl-chlorin (mTHPC) as the photosensitiser in superficial gastric cancer. METHODS: Twenty two patients with superficial early gastric cancer received mTHPC (0.075 mg/kg intravenously) and were treated 96 hours later with red light at 652 nm (20 J/cm2). Tumour response was assessed by endoscopy and extensive biopsy. RESULTS: Endoscopies performed two to three days after PDT showed a haemorrhagic fibrinoid necrosis of the mucosal layer. Complete remission was achieved in 16/22 (73%) patients: 13/16 (80%) with intestinal type cancer and 3/6 (50%) with a diffuse Lauren's carcinoma. The mean follow up period was 12 months and 20 months, respectively. An average of 1.8 treatment sessions was required. Severe side effects were not observed. Seven patients had mild to moderate skin photo-sensivity reactions; 12 had local pain after PDT for 1-10 days. CONCLUSION: PDT using mTHPC as the photosensitiser represents a safe and efficient method for topical treatment of early gastric cancer, especially of Lauren's intestinal carcinoma. If the preliminary results can be verified in larger patient series and during long term follow up, local treatment of early cancers of the stomach by PDT could be considered as a therapeutic option for selected patients.
Adult↗
[Photodynamic therapy of early squamous epithelial carcinomas and severe squamous epithelial dysplasias of the esophagus with 5-aminolevulinic acid].
INTRODUCTION: Photodynamic therapy (PDT) is a new local, endoscopically controlled therapeutic concept based on the selective sensitization of malignant and precancerous lesions prior to light-induced tissue destruction. 5-aminolaevulinic acid (5-ALA) appears to be a promising alternative photosensitizer with a high mucosa specificity without phototoxic side effects on the skin. We report on our experience with this new form of PDT in 24 patients. PATIENTS AND METHODS: Five females and 19 males (aged 50 to 79 years) with histologically proven high-grade dysplasia (n = 9) and early cancer (normal EUS or uTlNOMO, n = 15) of the esophagus were included in this study. Four to six hours after oral ingestion of 5-ALA (dosage of 60 mg/kg b.w.) laser light irradiation was conducted with a dye laser system (XP 800 KTP/YAG, Laserscope, San José, USA) at a wavelength of 635 nm. With a light dose of 150 J/cm2. RESULTS: The length of the segment with severe dysplasia or mucosal cancer varied between 0.5 and 9 cm (mean length: 3.6 cm). High-grade dysplasia was eradicated in all patients (9/9). In addition, 16 mucosal carcinomas in 15 patients were successfully treated in 8/16 cases with an average of 1.8 treatment sessions and a mean follow-up of 14.5 months (range: 3-31 months). A method-related mortality and morbidity was not observed. CONCLUSIONS: Severe dysplasia and superficial (< or = 2 mm) mucosal cancer of the esophagus can be completely ablated by 5-ALA-PDT. Patients with early carcinoma thicker than 2 mm are not suitable for 5-ALA-PDT. PDT with 5-ALA has few side effects and might offer an alternative to esophagectomy or radio-chemotherapy.
Administration, Oral↗
Malignant strictures. Thermal treatment.
Malignant stenoses can occur in any part of the gastrointestinal tract. Endoscopic treatment options are available, however, only for the rectosigmoid area, the esophagus, and the esophagocardial transition. Strictures in the esophageal region represent the quantitatively predominant type of stenoses encountered in everyday endoscopy.
Electrocoagulation↗
[Morphological changes in human colon carcinoma after chemotherapy with 5-fluorouracil--a study in the nude mouse model].
Colorectal cancer represents one of the most important challenges in the field of cancer chemotherapy. 5-fluorouracil (5-FU) is used as the first-choice chemotherapeutic agent in the treatment of advanced gastrointestinal cancer. Despite this fact very little is known about the morphological changes of colon carcinoma after treatment with 5-FU. Thymusaplastic nude mice (n = 59) with subcutaneously heterotransplanted human coloncarcinoma (tubulo-papillary adenocarcinoma, grade II-III) were treated with 5-FU (40 mg/kg/body weight i. p. for five days). The animals were sacrificed, tumors were removed at 0 h, 24 h, 36 h, 48 h, 54 h, 60 h, 66 h, 72 h, 94 h, 118 h, 240 h after chemotherapy and the tumor tissue was embedded for light-microscopic and ultrastructural examination. Hydropic mitochondria and cytoplasmatic vacuoles were observed in tumor cells as early as 0 h after chemotherapy. These changes displayed a focal pattern. Damaged tumor tissue was surrounded by tumor cells with intact ultrastructure. In some regions tumor cells were separated from the basal membrane and showed signs of necrosis. These focal changes within the tumor tissue were observed from 0-240 h after treatment. Tumor capillaries did not show any damage. Treatment with 5-FU led to focal cytotoxic effects in the tumor. The remaining intact vascular system of the tumor may be a target for new therapy modalities.
Adenocarcinoma, Papillary↗
Pharmacokinetics of 5-aminolevulinic-acid-induced porphyrins in tumour-bearing mice.
Photodynamic therapy and photodynamic diagnosis help to support efficient treatment of superficial and early-stage cancer. During the last few years, 5-aminolevulinic acid (5-ALA), a precursor of haemoglobin in the haem biosynthetic pathway, was used to stimulate endogenous porphyrin production. In the following the time dependence of 5-ALA-induced porphyrin concentration will be investigated on several tissues in an in-vivo tumour model. 5-ALA was administered intravenously at a concentration of 50 mg-1 body weight. According to a certain time schedule the animals were sacrificed and 12 different organs as well as the tumour were removed. During excitation with the violet light of a Kr+ laser, porphyrin fluorescence spectra in the range 550-750 nm could be detected on the tissue samples. The intensity of the emission spectra at lambda = 635 +/- 2 nm was taken as a measure of the porphyrin concentration. All tissues showed porphyrin fluorescence. Brightest fluorescence was found on the tumour. A maximum contrast of the fluorescence intensity between the tumour and the non-malignant organs of up to 30 was observed at 4-6 h post-injection. The kinetics of the porphyrin concentration depend on the organ. Simple mathematical models will be derived and discussed.
Aminolevulinic Acid↗