Influencia e impacto dentro de las relaciones personales

The major clinical problem of oesophageal and gastric cancer is profound dysphagia in the majority, leading to severe cachexia, often local discomfort and eventually aspiration pneumonia. Laser treatment offers effective tumour debulking for rapid relief of dysphagia, it can be performed as an out patient procedure, does not have systemic effects and serious complications are rare. The major drawback of laser is the need for repeated treatments every 5 weeks or so to maintain good swallowing (see chapter 2). This is because disease is left in the oesophageal wall and beyond the lumen in local nodes and thus tumour regrowth occurs fairly rapidly. Radiotherapy however has the potential for treating all the oesophageal tumour and the local regional draining sites (Tobias 1991) and thus should be complimentary to laser.

External beam radiotherapy alone relieves dysphagia slowly, often taking several weeks for maximal effect (Pearson 1978). A recent study of palliative radiotherapy (Caspers 1988) suggested that patients with relatively good swallowing enjoy improved survival over those who swallow poorly at presentation. There is thus both theoretical and clinical evidence to support the concept that a patient whose swallowing has been improved by laser recanalisation should benefit further from radiotherapy. There have, however only been a few studies (Bader 1986, Sander 1991, Renwick 1992) which have studied the combination of laser and radiotherapy, and intraluminal rather than external beam radiotherapy was used (Bader also gave external beam treatment to those with squamous cell cancers). Intraluminal radiotherapy (brachytherapy) causes superficial damage to the tumour, as there is a rapid fall off in dose with distance from the source, and is not as

effective in terms of irradiating the whole tumour as external beam treatment. These studies did however report prolonged dysphagia free intervals although only the first was randomised and in this study the benefit was only seen in patients with squamous cell cancers. The pilot study was designed to answer the following questions.

1) To determine if palliative external beam radiotherapy, a more widely available and practical technique than brachytherapy, may be a promising approach in reducing the frequency of follow up procedures following laser treatment alone.

2) To determine what radiotherapy dose regime would be appropriate in these patients.

3) If the approach appeared promising to provide data to aid designing a randomised study to test the combination treatment more rigourously.

3.2 M ethods

3.2.1 Patient sgkctign

The laser unit at University College Hospital acts as a tertiary referral centre for patients suffering from malignant dysphagia who are considered unsuitable for surgery. A smaller number of patients treated with laser (around 20%) present directly to the hospital. Patients recruited into this study were initially seen by us between September 1988 and June 1989. Patients with predominantly exophytic carcinomas of the oesophagus and gastric cardia were eligible for the study. All patients recruited were deemed inoperable either due to advanced disease or unacceptable anaesthetic risk. Five patients had documented metastatic disease, five had advanced local disease detected at CT scan and 3 had undergone laparotomy and their tumours could not be resected. A further nine were considered unsuitable for surgery due to age and/or general debility. Patients with a good technical result

from laser and swallowing fluids or better were assessed for radiotherapy by Dr Tobias (consultant radiotherapist) before trial entry. Those who had had previous radiotherapy were excluded. All patients had either squamous cell carcinomas of the oesophagus or adenocarcinomas of the cardia. Patients with malignancy arising in organs other than the oesophagus and causing dysphagia by direct invasion or metastatic spread were excluded. Full demographic data are given in table 3.1.

Table 3.1 Patient characteristics Total No Male/Female Mean age (yrs ± sd)

Squamous call carcinoma/Adenocarcinoma

Cardia/thoracic

Mean tumour length (Cm sd)

Métastasés

Inoperable- CT scan or at Laparotomy

Medically unfit 22 15/7 6 8 ( 11) 9/13 15/6 (1 anastomotic) 7(3) 5 8 9 7 0

3.2.2 E thical asp ects

All patients were instructed as to the nature of the study. Formal ethical committee approval was not considered necessary as both laser and external beam radiotherapy treatment are well established therapies for oesophageal cancer and all patients entered into the study were treated identically (no randomisation).

3.2.3 T ech niqu es

Endoscopic and laser technique has been discussed in detail in chapter 1. At initial endoscopy patients underwent laser sessions as appropriate to destroy intraluminal tumour and restore oesophageal patency. Oesophageal dilatations were performed for strictures if the endoscope would not pass in order to enable full evaluation of the tumour and improve access for optimal laser treatment. All patients were irradiated using supervoltage telethera^y (cobalt 60). The target volume was determined by the length of tumour with a 5cm margin at the upper and lower border of the tumour and a 3 cm margin circumferentially. The treatment was delivered by anterior and posterior opposed fields in all cases. In the early part of the study patients were initially given 20Gy in 5 or 10 fractions and six patients who had tolerated this dose well were given a further dose 20Gy dose either immediately or 4-6 weeks later (total dose 40Gy). It soon became apparent that most of these patients could not tolerate this total dose and subsequent patients all received 30Gy in 10 fractions. Twenty patients had to stay in hospital for DXRT. This increased the median lifetime total hospital stay to 21 days in comparison to historical in-patient times of around 14 days for laser only.

3.2.4 FoIIow-ud

All patients underwent follow up endoscopy three weeks after completion of radiotherapy (check endoscopy). Endoscopic findings were recorded as at initial endoscopy, and further laser treatment was applied only to polypoid tumour. All patients were subsequently contacted monthly by the research sister, Sally Thorpe,

to assess progress and the necessity for further treatment. Dysphagia score was recorded according to the scale previously used by us { O=normal; l=most solids; 2= semi solids; 3 =liquids only ;4=difficulty with liquids). Patients whose dysphagia grade deteriorated by one or more or who felt that their swallowing had deteriorated significantly were re-endoscoped for assessment and further therapy as appropriate.

3.2.5 Statistical methods

Proportions were tested using Chi squared test with Yate's correction and survival curves with the Log Rank test.