Laser irradiation of inoperable tumours of the colon and rectum

Combined endoscopic laser and radiotherapy palliation of advanced rectal cancer

BACKGROUND

In the palliative treatment of patients with advanced, inoperable rectal cancer, combined endoscopic laser and radiotherapy have been claimed to be more effective than laser therapy alone. The number of laser treatments, laser energy used, relapse rate, treatment of relapse, morbidity and survival in consecutive patients who were treated either by laser therapy alone or laser plus radiotherapy was compared.

METHODS

Prospective data were analysed with regard to number of treatments, laser energy used, relapse rate, morbidity and survival for 56 consecutive patients.

RESULTS

The crude relapse rate was significantly higher in the laser only group than in the laser plus radiotherapy group (58 and 15%, respectively; P = 0.002). There was no difference between the groups in the median total number of laser treatments or the mean total laser energy used. In patients experiencing a relapse, there was no difference in the median number of relapses, the number of laser treatments post-relapse or the total energy used post-relapse. Survival did not differ between the groups and there were no treatment-related deaths.

CONCLUSIONS

These findings demonstrate a clear reduction in relapse after using combined laser and radiotherapy to palliate patients with advanced rectal cancer with no appreciable additional morbidity and have encouraged continuing use of this treatment.

Superiority of Nd:YAG laser to cryosurgery in the treatment of rectal carcinoma

Laser coagulation (LC) by Nd:YAG laser and cryodestruction (CD) by insulated cryoprobe were done in 52 patients with carcinoma of the rectum (LC = 27, CD = 25). The patients were divided into four groups: group I, inoperable rectal carcinoma because of advanced stage of malignancy, severe concomitant disease, old age (LC = 14, CD = 12); group II, patient refused permanent colostomy (LC = 4, CD = 3); group III, polypoid lesion fulfilled the criteria of local excision (LC = 3, CD = 2); group IV, local recurrence after anterior resection (LC = 6, DC = 8). The mean hospital stay was 8.11 +/- 5.6 days for LC and 12.8 +/- 8.7 days for CD (p less than 0.05). For LC minimal or no sedation was needed, but for CD general anesthesia (n = 3) was occasionally necessary. Significant improvement was achieved in 85.18% (n = 23) of cases with LC and 56% (n = 14) of cases with CD (p less than 0.05). Complications after LC were mild (n = 7) to moderate (n = 3) and after CD they were moderate (n = 11) to severe (n = 2). Almost every patient with CD complained of moderate to severe discharge of malodorous necrotic tissue for a period of 2 weeks or more. In groups I, II, and IV patients with LC enjoyed a longer (81.08 +/- 47.48 days) trouble-free period than those with CD (43.3 +/- 13.45 days) (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Palliative laser therapy for tumours of the gastrointestinal tract

The argon ion and Nd: YAG lasers were used initially in the mid 1970s to produce haemostasis in acutely bleeding peptic ulcers. With the evolution of treatment techniques, the main area of use of the Nd: YAG laser has now become the palliation of upper and lower GI malignancies. Thermal ablation of tumours may be achieved endoscopically by non-contact laser application at high power, or in the contact mode using artificial sapphire probes at much lower energy levels. Still lower powers can be employed therapeutically using interstitial hyperthermia, and this is best applied endoscopically to exophytic tumour nodules in the gut lumen or to tumours localized ultrasonically in solid organs, such as the liver or pancreas. PDT involves destruction of previously photosensitized tumours by the cytotoxic action of singlet oxygen released on exposure of the neoplastic tissue to light of an appropriate wavelength. Although the theory is attractive, the available experimental and clinical information suggests that treatment should, for the present, be confined to small or early malignancies whose depth of invasion can be verified by endoscopic ultrasound or other imaging techniques. PDT carries the biological advantage of healing by regeneration with preservation of connective tissue stroma, while the Nd: YAG laser causes destruction by thermal coagulation or vaporization and subsequent healing by fibrosis. Laser therapy of GI tumours expands the range of therapeutic endoscopic procedures in a relatively safe and readily repeatable manner which achieves high patient tolerance. By reducing morbidity, mortality and time spent in hospital, it offers significant advantages in the palliative treatment of conditions previously managed by conventional surgery, and also offers opportunities for treatment of previously inoperable disorders. Developments in laser technology and diagnostic imaging techniques are likely to promote laser therapy in the future as a primary treatment modality.

Palliative laser therapy for inoperable rectal cancer--does it work? A prospective study of quality of life

Endoscopic neodymium yttrium aluminium garnet (Nd YAG) laser therapy, is a new and simple method for the palliative treatment of inoperable colorectal cancer. To date the authors have treated 70 patients and the value of this method was assessed prospectively in 14 patients. Quality of life was measured before, during, and after treatment. The quality of life (QL) index, a physician's assessment and a linear analogue self-assessment (LASA) were used. A close correlation was found between the two assessment methods (r = 0.79). Overall there was a significant improvement from the mean pretreatment score and the best score achieved posttreatment (QL: P = 0.002; LASA: P = 0.002). Patients with diarrhea, rectal bleeding, mucus discharge, or pain secondary to tumor bulk, will benefit most from this treatment. Malignant cachexia, pain secondary to sacral plexus involvement, tumor encroachment on the anal canal and/or sphincter dysfunction resulting from tumor invasion should be viewed as relative contraindications to laser therapy. The authors conclude that in selected patients endoscopic laser therapy can provide effective palliation in patients with malignant tumors of the rectum and descending colon.

Laser therapy in the management of benign and malignant tumours in the colon and rectum

Since 1983 the Neodymium-YAG laser has been used endoscopically to treat 93 patients with inoperable colorectal carcinoma and 18 patients with benign sessile adenomas. In an additional 11 patients with colorectal cancer, photodynamic therapy (PDT) has been applied using an argon-pumped dye laser. Objective and subjective measurements of quality of life have shown the beneficial effects of the Nd-YAG laser in the relief of symptoms, and four patients have apparently been rendered disease free. Benign tumours also respond to Nd-YAG ablation but close histological supervision is necessary to detect malignant transformation at an early stage. Although PDT may offer a potential for cure in small inoperable tumours, it seems likely that Nd-YAG laser treatment will remain the laser option of choice for advanced bulky tumours.

Risk factors which determine the long term outcome of Neodymium-YAG laser palliation of colorectal carcinoma

We have analysed the long term results of YAG laser palliation for incurable colorectal carcinoma in 88 patients. Although initial palliation was achieved in 82%, good palliation could only be maintained in 51% and 41% of patients surviving 6 months and 12 months respectively. The relative inefficacy of YAG laser therapy for palliation of rectal cancer is due to the failure to control extraluminal tumour growth, complications of YAG laser therapy and the poor general condition of these elderly patients. Factors influencing the efficacy of palliation, besides life expectancy, included T classification, and length of the neoplastic stricture. Treatment-related mortality due to perforation was 2.3%. YAG laser therapy, applied as the sole therapeutic modality, is effective for short term palliation of incurable colorectal carcinoma, but is not adequate for long term palliation in most patients. Trials should be conducted to study the effect of combined treatment (e.g. laser + radiotherapy) on palliation.

The palliative endoscopic treatment of inoperable oesophagogastric and rectal cancers: a low power direct contact laser technique

The palliative treatment of inoperable cancers of the oesophagus, gastric fundus and rectum can be difficult and unsuccessful. Laser beam irradiation therapy offers good palliation in the majority of patients but requires several treatment sessions to achieve this. We describe a small series of patients treated with a new direct contact low power laser technique using artificial sapphire probes. After one treatment, in patients with malignant dysphagia, two thirds could swallow solids and in patients with rectal cancers bleeding was stopped or reduced and diarrhoea stopped. The interval before a second treatment was needed was three and a half weeks. We feel this technique is a useful adjuvant to conventional laser therapy of inoperable gastrointestinal tract tumours, especially in providing effective palliation in one treatment session.