Lasers in rectosigmoid tumors

Endoscopic Treatment of Carpet-Like Adenomas of the Rectum

Background

Transanal microsurgery, endoscopic laser photocoagulation and snare resection have all been used to treat large sessile adenomas of the rectum alternatively to a surgical approach. However, such modalities are often defective due to the carpet-like shape and the frequently large extension of the lesions.

Methods

Ten patients with carpet-like adenoma were submitted to transanal endoscopic resection by urological resectoscope.

Results

Complete eradication was obtained in all lesions. The mean number of treatment sessions was 3 (range, 1-5). The mean time between the first treatment and the complete eradication was 6 months (range, 1-18). The only complications were an intraoperative and an early postoperative bleeding. There was no early or late mortality related to the procedure.

Conclusions

Transanal endoscopic resection by urological resectoscope appears to be a suitable therapeutic approach for sessile and carpet-like adenomas of the rectum or for pTI cancer in patients who refuse major surgery.

Resection of the Primary Tumor in Stage IV Colorectal Cancer: When Is It Necessary?

Management of metastatic colorectal cancer requires accurate staging and multidisciplinary evaluation, leading to a consensus treatment plan with the ultimate goal of increasing survival and improving the quality of life, while taking into consideration the patient's performance status, disease burden, and goals of care. Since the introduction of multidrug chemotherapeutic regimens, survival of patients with metastatic colorectal cancer has improved. Many patients with unresectable disease are undergoing surgery for asymptomatic primary tumors despite evidence that it is usually a futile intervention. Palliative measures for local control of the primary tumor include colonic stents, laser therapy, and fulguration.

Palliation of colorectal cancer

Patients with advanced incurable colorectal cancer (CRC) face a grim prognosis. The goal of palliative intervention is directed at alleviating disease-related symptoms and improving quality of life. The provision of optimal palliative care for these patients is a compound and demanding process. This dilemma becomes more challenging when patients with advanced metastatic colorectal disease present with an incurable and asymptomatic primary lesion. Treatment options are numerous and include a variety of surgical and nonsurgical interventions. Most data regarding the role of surgery in palliation of CRC are from retrospective, nonrandomized case series. Surgical resection may provide good palliation of symptoms and prevent future tumor-related complications. Metal stents are also able to provide good palliative relief of obstruction and should be used when appropriate. The best palliative care will often require a multidisciplinary approach that involves input from surgical and nonsurgical teams, where treatment plans will be made in accordance with the wishes of the patient and family with a goal of decreasing morbidity and a focus on quality of life.

Endoscopic approaches for palliation of luminal gastrointestinal obstruction

Much of the workload of a typical gastroenterologist is devoted to screening patients for gastrointestinal malignancies. Efforts such as colorectal cancer screening via colonoscopy and endoscopic surveillance of patients with Barrett's esophagus are widespread and widely endorsed. In recent years, the armamentarium of endoscopy has broadened considerably and now affords physicians a variety of nonsurgical means to palliate malignant obstruction of the gastrointestinal tract. This article reviews endoscopic techniques to treat malignant esophageal, biliary, small bowel, and colonic obstruction.

Management of malignant colonic obstruction

Malignant large bowel obstruction remains a clinical entity that is commonly encountered despite our advances in screening for colorectal cancer. Patients with malignant large bowel obstruction usually have advanced colorectal cancer and are often poor operative candidates, yet these patients are in need of treatment and colonic decompression. Surgical therapies are available and can offer good outcomes in selected patients. Patients who have curative or palliative surgeries planned should routinely undergo preoperative endoscopic decompression. Available options for decompression include the placement of colonic decompression tubes, ablative methods such as the use of lasers, argon plasma coagulators, and the use of self-expanding metal stents. The author favors the use of self-expanding metal stents, as these devices provide rapid colonic decompression, create a wide luminal diameter, and are applicable in patients requiring preoperative decompression and bowel preparation as well as in patients undergoing palliative therapy only. Patients who go on to surgery can have the stent and tumor removed en bloc at the time of the procedure, whereas patients who are only candidates for palliation can have the stents left in place as permanent decompressive devices with minimal morbidity and mortality.

ASGE guideline: the role of endoscopy in the diagnosis, staging, and management of colorectal cancer

This is one of a series of statements discussing the utilization of GI endoscopy in common clinical situations. The Standards of Practice Committee of the American Society for Gastrointestinal Endoscopy prepared this text. In preparing this guideline, a MEDLINE literature search was performed, and additional references were obtained from the bibliographies of the identified articles and from recommendations of experts. When little or no data exist from well-designed prospective trials, emphasis is given to results from large series and reports from recognized experts. Guidelines for appropriate utilization of endoscopy are based on a critical review of the available data and expert consensus. Further controlled clinical studies are needed to clarify aspects of this statement and revision needed to clarify aspects of this statement and revision may be necessary as new data appear. Clinical consideration may justify a course of action at variance to the recommendations.

Endoscopic methods (other than stents) for palliation of rectal carcinoma

Patients with unresectable or metastatic rectal cancer may have symptoms of obstruction, bleeding, pain, or tenesmus. Insertion of a self-expandable metal stent is the most durable nonsurgical method for relieving obstruction and has been reviewed in the previous article. Other endoscopic methods of palliating obstruction have been largely replaced by expandable metal stent placement. However, laser ablation is still a useful therapy for some patients, particularly when the predominant symptom is rectal bleeding. The indications and results of endoscopic laser therapy along with other endoscopic treatments for the palliation of rectal cancer will be reviewed here.

Endoscopic palliation of colorectal cancer

Multiple endoscopic options exist for physicians seeking to provide palliative therapy for patients with colorectal cancer. Endoscopic decompression tubes can allow urgent stabilization for patients with malignant obstruction requiring some form of surgical palliation. Patients who are not candidates for palliative surgery can experience good symptomatic relief from malignant large bowel obstruction via laser therapy or placement of a colonic stent. Laser therapy can be used in conjunction with SEMS to recanalize and decompress large bowel in certain situations. The use of colonic stents is rapidly becoming more commonplace as acceptance of the technique becomes more widespread. Patients with unresectable disease may be able to avoid surgery altogether and achieve successful and lasting palliation of large bowel obstruction. Overall, they provide effective and durable palliation in patients with malignant obstruction, have an excellent risk/benefit profile, and are within the technical means of both gastroenterologists and interventional radiologists.

Outcome of argon beam and LASER ablation of large rectal adenomas

OBJECTIVE: Endoscopic ablation of large rectal adenomas is being increasingly used as primary treatment. Despite the avoidance of general anaesthesia and the prevention of more major procedures, patients undergoing endoscopic ablation have the disadvantage of multiple treatment sessions and the lack of adequate tissue sample for complete histological study. The aim of this study was to analyse the outcome of all patients with large rectal polyps treated with endoscopic ablation. PATIENTS AND METHODS: Between 1993 and 1998, 29 patients who underwent endoscopic ablation of large rectal adenoma were identified. All their case notes were analysed and information was collected on recurrence, treatment episodes, complications, the incidence of carcinoma and the necessity for further procedures. RESULTS: At a median 40 (range 4-67) months follow-up, 41% of patients had recurrence of their adenoma and 14% had been diagnosed with adenocarcinoma. Only 24% of patients had been discharged while 21% were clear but were still under surveillance. Seven (24%) patients had complications, 6 stenosis and one severe bleeding. All stenosis occurred in patients who had more than 10 treatment sessions. In all, 31% of patients needed further endoanal or abdominal surgery and the median time to making this decision was 28 (range 4-66) months. There were no deaths. CONCLUSION: Laser and argon ablation of large rectal adenomas has proved very disappointing. It should be reserved for patients who are unfit to undergo general anaesthesia.

Local methods of treatment of rectal cancer

Over 11 000 new cases of rectal cancer are reported in the UK each year. Recent technical advances have increased interest in local management of the disease. The introduction of screening for colorectal cancer will potentially lead to an increased number of early rectal cancers suitable for local curative treatment. In addition, as the proportion of elderly patients in the population rises, local methods of treatment of rectal cancer will become increasingly important in this group of patients with comorbid disease. A literature search was performed on Medline database for English language publications on local treatments of rectal carcinoma. Preoperative assessment, selection of patients, local therapeutic and palliative methods of treatment were evaluated. Local methods of treatment can be used for potentially curative operations for rectal cancer. Preoperative endoanal ultrasound appears to be the most useful investigation for determining depth of local invasion. Transanal endoscopic microsurgery has extended the boundaries of local surgery and permits access to the mid and upper rectum with results similar to those of conventional local techniques. Laser therapy and transanal resection provide the best form of palliation for more advanced rectal carcinomas.

Current concepts in gastrointestinal photodynamic therapy

OBJECTIVE

To review current concepts of photodynamic therapy (PDT) applied to the treatment of tumors of the gastrointestinal tract.

SUMMARY BACKGROUND DATA

PDT initially involves the uptake or production of a photosensitive compound by tumor cells. Subsequent activation of the photoreactive compound by a specific wavelength of light results in cell death, either directly or as a result of vascular compromise and/or apoptosis.

METHODS

The authors selectively review current concepts relating to photosensitization, photoactivation, time of PDT application, tissue selectivity, sites of photodynamic action, PDT effects on normal tissue, limitations of PDT, toxicity of photosensitizers, application of principles of PDT to tumor detection, and current applications of PDT to tumors of the gastrointestinal tract.

RESULTS

PDT is clearly effective for small cancers, but it is not yet clear in which cases such treatment is more effective than other currently acceptable approaches. The major side effect of PDT is cutaneous photosensitization. The major limitation of PDT is depth of tumor kill. As data from current and future clinical trials become available, a clearer perspective of where PDT fits in the treatment of cancers will be gained. Many issues regarding pharmacokinetic data of photosensitizers, newer technology involved in light sources, optimal treatment regimens that take advantage of the pharmacophysiology of photoablation, and light dosimetry still require solution. One can foresee application of differing sensitizers and light sources depending on the specific clinical situation. As technologic advances occur, interstitial PDT may have significant application.

CONCLUSIONS

PDT has a potentially important role either as a primary or adjuvant mode of treatment of tumors of the gastrointestinal tract.

Endoscopic Nd:YAG laser therapy for villous adenomas of the right colon

BACKGROUND

Endoscopic laser therapy is considered an acceptable treatment of benign colorectal adenomas. The aim of our study was to evaluate the efficacy of Nd:YAG laser to ablate right-sided colonic sessile adenomas.

METHODS

Between January 1990 and February 1996, 56 patients underwent laser therapy because of high operative risk or refusal of surgery. Lesions were located as follows: cecum (23), ascending, (15), and hepatic flexure (18). Six patients (10.7%) had multiple polyps in the ascending colon. Histologic examination showed a tubulovillous pattern in 20 (35.7%) and a villous pattern in 36 (64.3%). Low-grade dysplasia was detected in 44 patients (78. 5%) and high-grade dysplasia in 12 (21.4%).

RESULTS

The number of laser sessions ranged between 1 and 6 (median 3) and complete ablation, histologically confirmed, was achieved in 49 cases (87.5%). Seven patients (12.5%) underwent surgery: 2 for incomplete tumor destruction, 3 because of invasive carcinoma on repeated biopsies. Two patients (3.6%) had complications (one perforation of the cecum and one hemorrhage). Follow-up ranged from 6 to 60 months and no recurrences were observed.

CONCLUSION

Laser therapy is an effective method for the destruction of sessile adenomas of the right colon in selected patients.