386
Journal of the Royal Society of Medicine Volume 84 June 1991
this time. Thence it may be possible to eradicate the disease altogether (save for the 'silent' cases). E J FIELD Naomi Bramson Research Centre Science Park, University of Warwick
Coventry CV4 7EZ References 1 Gowers W. A lecture on abiotrophy. Lancet 1902;i:1003-7 2 Hassin GB. Studies in the pathogenesis of multiple sclerosis. Arch Neurol Psychiatry 1922;7:589-607 3 Lumsden CE. Neuropathology of multiple sclerosis. In: Vinken PJ, Bruyn GW, eds. Handbook of clinical neurology. Multiple sclerosis and other demyelinating diseases vol 9. Amsterdam: North Holland, 1970:66 4 Allen IV, McKeown SR. A histological, histochemical and biochemical study of the macroscopically normal white matter in multiple sclerosis. JNeurol Sci 1979;41:81-91 5 Field EJ. Conclusion: Can MS be virtually eradicated? In: Multiple sclerosis. A conceptual reappraisal with heuristic implications. Springfield, Illinois: CC Thomas, 1989:231-5
I was interested to read the article by Richard Hughes (February 1990 JRSM, p 63) on prospects for treatments in multiple sclerosis (MS), and note that in spite of reviewing some of the more exciting aspects of MS relevant research he remains 'gloomy' about specific immunotherapy. The fact there is an emerging consensus that MS is largely immunologically mediated can only be good news in the long term. Disappointments with steroids and aziothioprine are only to be expected because of their blunderbus effects re immunosuppression. It is important to remember that a huge global effort is underway to produce new generations of specific immunosuppressants. One such already available is FK506 and surely heralds the availability of many more prototype drugs for clinical testing. Whilst I agree with his multifactorial pathogenesis scenario I do not necessarily think that it should result in a gloomy outlook with regards to therapy. Indeed he referenced a final common pathway approach which is one of several requiring careful considered analysis. The discovery of T cell receptor (TCR) V(3 associations with multiple sclerosis which are not readily reproducible may indicate that VF3 TCR alone are not the causal association of MS, but instead suggest that MHC class II/V,8 combinations may be more likely to result in an immune response to a pathogen which results in neurological damage. After spending the last few years searching for the 'MS virus' it is refreshing to think that basic research has given us new tools to tackle how we may best design specific immunotherapies for this tragic disease, rather than search in vain for a specific causative agent to vaccinate against. This coupled with the aforementioned drug research programme should at least give us some hope to be optimistic about research into MS. A G DALGLEISH Clinical Research Centre Watford Road, Harrow HAl 3UJ
Marihuana and mouth cancer Boyle et al. in their review of the epidemiology of mouth cancer (November 1990 JRSM, p 724) .made no mention of marihuana smoking as a risk factor. During the last 5 years there have been 13 reports of cancer of the mouth and larynx among chronic marihuana smokers in Australia and the United
States'-3. Five of the 13 had no other risk factors and all were young (< 55 years old). The same literature search revealed only three reports of lung cancer amongst marihuana smokers2'4. This evidence suggests that marihuana smoking has a greater carcinogenic effect on the upper than the lower airways. If true this would correlate with respiratory function studies which demonstrate definite abnormalities in the proximal airways, but not in the peripheral airways5'6. It has been hypothesized that the rapid, deep inhalation technique usually employed in smoking marihuana leads to earlier deposition of particulate material due to turbulence and inertial impaction5. Whatever the reason, marihuana smoking as a possible cause of oral cancer deserves mention and further study. The Prince of Wales Hospital G A CAPLAN Randwick, NSW 2031, Australia References 1 Caplan GA, Brigham BA. Marijuana smoking and carcinoma of the tongue: is there an association? Cancer 1990;66:1005-6 2 Donald PJ. Marijuana smoking: possible cause of head and neck carcinoma in young patients. Otolaryngol Head Neck Surg 1986;94:517-21 3 Taylor FM. Marijuana as a potential respiratory tract carcinogen: a retrospective analysis of a community hospital population. South Med J 1988;81:1213-16 4 Ferguson RP, et aL Metastatic lung cancer in a young marijuana smoker. JAMA 1989;261:41-2 5 Taskin DP, et al. Respiratory status of seventy four habitual marijuana smokers. Chest 1980;78:699-706 6 Tashkin DP, et aL Respiratory symptoms and lung function in habitual heavy smokers of maruaa alone, smokers of marijuana and tobaoo, smokers of tobacco alone and nonsmokers. Am Rev Respir Dis 1987;136:209-16
Paget's disease of the anus I read with interest the case report by Rosin (February 1991 JRSM, p 112). I have now treated five elderly women with extramammary Paget's disease of the vulva with Etretinate. The first of these cases I reported in Retinoids (vol. 8, p 32). None of the patients was fit for extensive surgery and had an excellent response to a very small dose. I started all of them on 25 mg Etretinate daily and maintained them on 10 mg daily. There were few untoward sideeffects. On stopping treatment there was some mild recurrence but because of the mild nature ofthe sideeffects I have left them on Etretinate 10 mg daily almost indefinitely. Glan Clwyd Hospital E S EMSLIE Bodelwyddan, Rhyl, Clwyd LL18 5UJ
Pyoderma gangrenosum I was interested to read the letter by Heaton (February 1991 JRSM, p 123), regarding their experience of the use of cyclosporin A in a patient with pyoderma gangrenosum. We have also reported the successful use of this drug in a patient with a 14-year history of pyoderma gangrenosum unresponsive to a variety of systemic and topical treatments'. R K CURLEY
St Helens Hospital Marshalls Cross Road, St Heln WA9 3DA
References 1 Curley RK, Macfarlane AW, Vickers CFH. Pyoderma
gangrenosum treated with cyclosporum A. Br JDermatol 1985;113:601-4
Journal of the Royal Society of Medicine Volume 84 June 1991
this time. Thence it may be possible to eradicate the disease altogether (save for the 'silent' cases). E J FIELD Naomi Bramson Research Centre Science Park, University of Warwick
Coventry CV4 7EZ References 1 Gowers W. A lecture on abiotrophy. Lancet 1902;i:1003-7 2 Hassin GB. Studies in the pathogenesis of multiple sclerosis. Arch Neurol Psychiatry 1922;7:589-607 3 Lumsden CE. Neuropathology of multiple sclerosis. In: Vinken PJ, Bruyn GW, eds. Handbook of clinical neurology. Multiple sclerosis and other demyelinating diseases vol 9. Amsterdam: North Holland, 1970:66 4 Allen IV, McKeown SR. A histological, histochemical and biochemical study of the macroscopically normal white matter in multiple sclerosis. JNeurol Sci 1979;41:81-91 5 Field EJ. Conclusion: Can MS be virtually eradicated? In: Multiple sclerosis. A conceptual reappraisal with heuristic implications. Springfield, Illinois: CC Thomas, 1989:231-5
I was interested to read the article by Richard Hughes (February 1990 JRSM, p 63) on prospects for treatments in multiple sclerosis (MS), and note that in spite of reviewing some of the more exciting aspects of MS relevant research he remains 'gloomy' about specific immunotherapy. The fact there is an emerging consensus that MS is largely immunologically mediated can only be good news in the long term. Disappointments with steroids and aziothioprine are only to be expected because of their blunderbus effects re immunosuppression. It is important to remember that a huge global effort is underway to produce new generations of specific immunosuppressants. One such already available is FK506 and surely heralds the availability of many more prototype drugs for clinical testing. Whilst I agree with his multifactorial pathogenesis scenario I do not necessarily think that it should result in a gloomy outlook with regards to therapy. Indeed he referenced a final common pathway approach which is one of several requiring careful considered analysis. The discovery of T cell receptor (TCR) V(3 associations with multiple sclerosis which are not readily reproducible may indicate that VF3 TCR alone are not the causal association of MS, but instead suggest that MHC class II/V,8 combinations may be more likely to result in an immune response to a pathogen which results in neurological damage. After spending the last few years searching for the 'MS virus' it is refreshing to think that basic research has given us new tools to tackle how we may best design specific immunotherapies for this tragic disease, rather than search in vain for a specific causative agent to vaccinate against. This coupled with the aforementioned drug research programme should at least give us some hope to be optimistic about research into MS. A G DALGLEISH Clinical Research Centre Watford Road, Harrow HAl 3UJ
Marihuana and mouth cancer Boyle et al. in their review of the epidemiology of mouth cancer (November 1990 JRSM, p 724) .made no mention of marihuana smoking as a risk factor. During the last 5 years there have been 13 reports of cancer of the mouth and larynx among chronic marihuana smokers in Australia and the United
States'-3. Five of the 13 had no other risk factors and all were young (< 55 years old). The same literature search revealed only three reports of lung cancer amongst marihuana smokers2'4. This evidence suggests that marihuana smoking has a greater carcinogenic effect on the upper than the lower airways. If true this would correlate with respiratory function studies which demonstrate definite abnormalities in the proximal airways, but not in the peripheral airways5'6. It has been hypothesized that the rapid, deep inhalation technique usually employed in smoking marihuana leads to earlier deposition of particulate material due to turbulence and inertial impaction5. Whatever the reason, marihuana smoking as a possible cause of oral cancer deserves mention and further study. The Prince of Wales Hospital G A CAPLAN Randwick, NSW 2031, Australia References 1 Caplan GA, Brigham BA. Marijuana smoking and carcinoma of the tongue: is there an association? Cancer 1990;66:1005-6 2 Donald PJ. Marijuana smoking: possible cause of head and neck carcinoma in young patients. Otolaryngol Head Neck Surg 1986;94:517-21 3 Taylor FM. Marijuana as a potential respiratory tract carcinogen: a retrospective analysis of a community hospital population. South Med J 1988;81:1213-16 4 Ferguson RP, et aL Metastatic lung cancer in a young marijuana smoker. JAMA 1989;261:41-2 5 Taskin DP, et al. Respiratory status of seventy four habitual marijuana smokers. Chest 1980;78:699-706 6 Tashkin DP, et aL Respiratory symptoms and lung function in habitual heavy smokers of maruaa alone, smokers of marijuana and tobaoo, smokers of tobacco alone and nonsmokers. Am Rev Respir Dis 1987;136:209-16
Paget's disease of the anus I read with interest the case report by Rosin (February 1991 JRSM, p 112). I have now treated five elderly women with extramammary Paget's disease of the vulva with Etretinate. The first of these cases I reported in Retinoids (vol. 8, p 32). None of the patients was fit for extensive surgery and had an excellent response to a very small dose. I started all of them on 25 mg Etretinate daily and maintained them on 10 mg daily. There were few untoward sideeffects. On stopping treatment there was some mild recurrence but because of the mild nature ofthe sideeffects I have left them on Etretinate 10 mg daily almost indefinitely. Glan Clwyd Hospital E S EMSLIE Bodelwyddan, Rhyl, Clwyd LL18 5UJ
Pyoderma gangrenosum I was interested to read the letter by Heaton (February 1991 JRSM, p 123), regarding their experience of the use of cyclosporin A in a patient with pyoderma gangrenosum. We have also reported the successful use of this drug in a patient with a 14-year history of pyoderma gangrenosum unresponsive to a variety of systemic and topical treatments'. R K CURLEY
St Helens Hospital Marshalls Cross Road, St Heln WA9 3DA
References 1 Curley RK, Macfarlane AW, Vickers CFH. Pyoderma
gangrenosum treated with cyclosporum A. Br JDermatol 1985;113:601-4
