In his commentary on the treatment of large uterine fibroids (Vol 103, June 1996)1 in which treatment of these tumours by interstitial thermotherapy by certain overseas gynaecologists is writ large, Chris Sutton has omitted to mention several publications from this country. The birth of interstitial laser—induced thermotherapy or interstitial laser photocoagulation took place in London in 1983. Experimental work was in live animals. Later it was used to treat various tumours in human organs (e.g. brain, liver, pancreas, prostate, and also fibroids)2. Twenty years ago I used the monopolar diathermy to coagulate small fibroids but adhesion formation at the site of treatment was thought to result from damage or necrosis of the false capsule. To avoid this holes were drilled in the false capsule with the carbon dioxide laser before insertion of the monocular probe3. I also used bipolar diathermy. However, since diathermy machines are arbitrarily calibrated, treatment cannot be standardised and, consequently, comparatively small variations in technique can change substantially the effective dose and depth of penetration. This form of treatment was therefore abandoned in favour of the KTP/YAG laser. Preliminary work was carried out at laparotomy with the laser to determine the energy needed to coagulate the fibroids and to destroy the oestrogen receptors4 prior to myomectomy. During the last five years some 750 fibroids have been coagulated with the KTP/YAG or diode laser at laparoscopy or hysteroscopy, and also percutaneously5. The results of the last five years of treatment and research, totalling 250 patients, including women of child bearing age who have since been delivered of normal babies, have been presented in international congresses around the world, and, most recently, at the 1st Congress of the World Association for Laser Therapy in Jerusalem, in May 1996.

The complications that have been mentioned in the commentary could have been foretold even before this technique was used in humans. We have used high power Nd:YAG laser of 80 Watts (W). Although 50–80 W have been used under water within the uterus or bladder or pulsed with coolant in contact or noncontact mode, it is quite contraindicated in interstitial hyperthermia. The concept of delivering the bare fibre into the centre of the tumour is different. In this situation the response to laser light occurs in a very confined space and, if the delivery of energy is too high and too fast, cellular water vaporises into steam which has no avenue of escape. The pressure rises within the tissue leading to a mini—explosion, massive charring and incandescence so that the local temperature could rise to more than 2000°C. This produces tissue burns rather than coagulation. The result is haemorrhage, sloughing and subsequent adhesion formation. More serious than this, however, is the fact that the excessive heat produced in such a confined space causes burning and breakage of the quartz bare fibre tip in the tissue. The effects of the glass laser tip breaking and remaining in the body are unknown. However it is obvious that this is very dangerous since the glass tip may travel around the systems of the body and lodge in a vital organ, which could be fatal.

Thus, interstitial laser-induced hyperthermia is best performed at very low power of 2 W in the liver and 4–8 W in a fibroid depending on the consistency of the fibroid and the method employed (with multiple fibres it was found that 4 W was sufficient). Therefore, in view of the fact that lower power interstitial laser photocoagulation has been used for the past thirteen years on many different types of tumour, including fibroids, with well documented evidence of encouraging results, which do not appear to have been studied, we feel that Sutton should withhold opinion until a multicentre trial of the correct procedure has been carried out. Only then can judgement be given on this very promising technique for the treatment of tumours.


  1. Top of page
  2. References
  • 1
    Sutton CJG. Treatment of large uterine fibroids. Br J Obstet Gynaecol 1996; 103: 494496.
  • 2
    Chapman R. Low power interstitial photocoagulation of uterine leiomyomas by KTP/YAG laser. Lasers in Medical Science 1994; 9: 3746.
  • 3
    Chapman R. Treatment of uterine leiomyomas by interstitial hyperthemia. GynaecolEndoxc 1993; 2: 227234.
  • 4
    Chapman R. Low power interstitial photocoagulation of uterine leiomyomas by KTP/YAG laser: a review of 50 consecutive cases. SPIE Proceedings of Medical Applications of Lasers II 1994; 2327: 304312.
  • 5
    Chapman R. A new modality for the treatment of leiomyomas using a multiple fibre with diode laser [prize winning poster], 27th British Congress of Obstetrics and Gynaecology; Dublin ; 1995.