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Embolisation of renal carcinoma
CORRESPONDENCE
335
Correspondence Letters are published at the discretion o f the Editor. Opinions expressed by correspondents are not necessarily those o f the Editor. Unduly long letters may be returned to the authors for shortening. Letters in response to a paper may be sent to the authors of the paper so that the reply can be published in the same issue. Letters should be typed double spaced and should be signed by all authors personally. References should be given in the style specified in the Instructions to Authors at the front o f the Journal. EMBOLISATION OF RENAL CARCINOMA SIR- The two recent papers concerned with the means of embolisation of kidneys with renal cell carcinoma (Wells et al., 1983; McIvor et al., 1984) are both of considerable interest, since if kidneys are to be infarcted the technique is important. Wells' use of the ethanol technique is probably much simpler for the general radiologist than using coils, but does it reliably cause infarction? In experiments with ethanol in normal rat kidneys we have seen very patchy infarction and wonder whether segmental artery spasm may protect the more distal cortical vessels. McIvor's results suggest that occlusion of the main vessel is most important, but this may stimulate collateral circulation to the tumour if the vessels of the tumour bed are not occluded as well as the main supply. The position of the coil may be important at surgery and our surgeons prefer the coil to be situated at the hilum of the kidney. Wallace et al. (1981) considered that overload of contrast medium to the remaining kidney may have caused renal failure and subsequent death in some patients, so we are wary of doing an aortogram at the end of the procedure. The means of embolisation are important in achieving infarction but the purpose and effect of the procedure on the patient have not been discussed in any depth by either author. The declared purposes of renal embolisation to infarct the kidney, help the surgeon by making the operation easier, reduce haematuria and possibly increase patient survival have not changed since the original paper by Almgard et al. (1973). In our experience, infarction is usually incomplete, the patients are distressed and the surgeon is not particularly helped (Teasdale et al. 1982). Useful as the kidney is in its role as a test-bed for practising techniques of embolisation, we feel that the time has come to test the rationale of renal infarction in a prospective randomised trial. We have now commenced such a trial, and would welcome the cooperation of any radiologists interested in the subject. W. D. JEANS Department o f Radiodiagnosis Bristol Royal Infirmary Bristol
References
Almgard, L. E., Fernstrom, I., Haverling, M. & Ljunquist, A. (1973). Treatment of renal adenocarcinoma by embolic occlusion of the renal circulation. British Journal of Urology, 45, 474-479. Mclvor, J., Kaisary, A. V., Williams, G. & Grant, R. W. (1984). Tumour infarction after pre-operative embolisation of renal carcinoma. Clinical Radiology, 35, 59-64. Teasdale, C., Kirk, D., Jeans, W. D., Penry, J. B., Tribe, C. T. & Slade, N. (1982). Arterial embolisation in renal carcinoma: a useful procedure? British Journal of Urology, 54, 616-619. Wallace, S., Chuang, V. P., Swanson, D., Bracken, B., Hersh, E. M., Ayala, A. & Johnson, D. (1981). Embolisation of renal carcinoma. Radiology, 138, 563-570. Wells, I. P., Hammonds, J. C. & Franklin, K. (1983). Embolisation of hypernephromas: A simple technique using ethanol. Clinical Radiology, 34, 689-692. SIR - I was interested to read Dr Jeans' comments about the use of ethanol for renal embolisation. It has been established in work with dogs (Ellman et al., 1980; Buchta et al., 1982) that the initial damage to the kidney after injection of ethanol occurs to the lamina tara externa of the glomerular capillaries as well as to the ultrastructure of the gIomerular endothelial, epithelial and mesangial cells. Main renal artery thrombosis is felt to be a secondary, delayed effect due to the lack of blood flow through an already irreversibly devitalised organ. This is borne out in clinical practice: the immediate post-embolisation arteriogram, and in particular the patency of the main renal artery, being a poor guide to the amount of eventual infarction. It must be remembered, therefore, that the effect of ethanol is primarily chemical
and that some time should elapse before nephrectomy if maximum infarction is to be obtained. A minimum of 7 days is suggested. In the absence of any details of technique, in particular the time between embolisation and harvesting the kidneys and the amount and rate of injection of ethanol used, I cannot comment on why Dr Jeans was only able to obtain patchy infarction in rats. This is certainly contrary to the published work in animal models. I would welcome a prospective, randomised trial to assess the efficacy of pre-operative embolisation of hypernephromas. Because of the varying techniques of embolisation that are likely to be used, and the inevitably subjective assessment by the surgeons of the ease of nephrectomy, as well as the large differences that occur in the vascularity and prognosis of these tumours, I think the results may not be too easy to ifiterpret. We continue to use ethanol injected through a balloon catheter routinely for embolisation pre-operatively and remain impressed by the ease, safety and efficacy of the technique. I. P. WELLS Radiodiagnostic Department Derriford Hospital Plymouth References
Buchta, K., Sands, J., Rosenkrantz, H. & Roche, W. D. (1982). Early mechanism of action of arterially infused alcohol U.S.P. in renal devitalization. Radiology, 145, 45-48. Ellman, B. A., Green, C. E., Eigenbrodte, E., Garriot, J. C. & Curry, T. S. (1980). Renal infarction with absolute ethanol. Investigative Radiology, 15, 318-322. SIR- Dr Jeans is quite right to point out that our paper did not discuss the benefits of pre-operative embolisation of renal carcinoma in any depth and dealt largely with technical aspects of the procedure. The aim of our paper was to describe and document a technique which could be relied upon to produce tumour infarction in excess of 50% as it seems likely that the therapeutic benefit would depend upon the extent of tumour infarction. The immediate benefits of pre-operative embolisation are already well established and we felt that we had little to add to previously published papers. There is little doubt that the procedure reduces the vascularity of renal carcinomas and makes subsequent nephrectomy technically easier (Mee and Heap, 1978; Giuliani et al., 1981; Wallace et al., 1981), that it can shorten the time required for nephrectomy (Hlava et al., 1976) and that it often reduces the operative blood loss (Singsaas et al., 1979). Dr Jeans has pointed out that renal artery embolisation is often distressing to the patient and we would agree that the potential therapeutic benefit should be weighed against the possible morbidity. In our series, the 'post-infarcfion' syndrome of renal pain, fever and nausea occurred in most patients and 17 required narcotic analgesics for adequate relief. There were two serious complications: one patient developed occlusion of the right anterior tibial artery 4h after embolisation, but the foot returned to normal 24h later after an exploratory operation and treatment with intravenous heparin (Kaisary et al., 1982) and another patient developed renal failure 3 days after the procedure and required dialysis before recovering completely. We agree that the important question is the effect of the procedure on patient survival, but we were unable to draw any useful conclusions from our 30 patients at the time we submitted the paper. Our figures showed that survival was longer in patients with localised disease (Stages 1 and 2; Robson et al. (1969)) than in patients with widespread disease (Stages 3 and 4) but this observation has often been made in the past. The course of two of the four patients with radiological evidence of pulmonary metastases at the time of embolisation and nephrectomy was unexpected and has been described more fully in another paper
335
Correspondence Letters are published at the discretion o f the Editor. Opinions expressed by correspondents are not necessarily those o f the Editor. Unduly long letters may be returned to the authors for shortening. Letters in response to a paper may be sent to the authors of the paper so that the reply can be published in the same issue. Letters should be typed double spaced and should be signed by all authors personally. References should be given in the style specified in the Instructions to Authors at the front o f the Journal. EMBOLISATION OF RENAL CARCINOMA SIR- The two recent papers concerned with the means of embolisation of kidneys with renal cell carcinoma (Wells et al., 1983; McIvor et al., 1984) are both of considerable interest, since if kidneys are to be infarcted the technique is important. Wells' use of the ethanol technique is probably much simpler for the general radiologist than using coils, but does it reliably cause infarction? In experiments with ethanol in normal rat kidneys we have seen very patchy infarction and wonder whether segmental artery spasm may protect the more distal cortical vessels. McIvor's results suggest that occlusion of the main vessel is most important, but this may stimulate collateral circulation to the tumour if the vessels of the tumour bed are not occluded as well as the main supply. The position of the coil may be important at surgery and our surgeons prefer the coil to be situated at the hilum of the kidney. Wallace et al. (1981) considered that overload of contrast medium to the remaining kidney may have caused renal failure and subsequent death in some patients, so we are wary of doing an aortogram at the end of the procedure. The means of embolisation are important in achieving infarction but the purpose and effect of the procedure on the patient have not been discussed in any depth by either author. The declared purposes of renal embolisation to infarct the kidney, help the surgeon by making the operation easier, reduce haematuria and possibly increase patient survival have not changed since the original paper by Almgard et al. (1973). In our experience, infarction is usually incomplete, the patients are distressed and the surgeon is not particularly helped (Teasdale et al. 1982). Useful as the kidney is in its role as a test-bed for practising techniques of embolisation, we feel that the time has come to test the rationale of renal infarction in a prospective randomised trial. We have now commenced such a trial, and would welcome the cooperation of any radiologists interested in the subject. W. D. JEANS Department o f Radiodiagnosis Bristol Royal Infirmary Bristol
References
Almgard, L. E., Fernstrom, I., Haverling, M. & Ljunquist, A. (1973). Treatment of renal adenocarcinoma by embolic occlusion of the renal circulation. British Journal of Urology, 45, 474-479. Mclvor, J., Kaisary, A. V., Williams, G. & Grant, R. W. (1984). Tumour infarction after pre-operative embolisation of renal carcinoma. Clinical Radiology, 35, 59-64. Teasdale, C., Kirk, D., Jeans, W. D., Penry, J. B., Tribe, C. T. & Slade, N. (1982). Arterial embolisation in renal carcinoma: a useful procedure? British Journal of Urology, 54, 616-619. Wallace, S., Chuang, V. P., Swanson, D., Bracken, B., Hersh, E. M., Ayala, A. & Johnson, D. (1981). Embolisation of renal carcinoma. Radiology, 138, 563-570. Wells, I. P., Hammonds, J. C. & Franklin, K. (1983). Embolisation of hypernephromas: A simple technique using ethanol. Clinical Radiology, 34, 689-692. SIR - I was interested to read Dr Jeans' comments about the use of ethanol for renal embolisation. It has been established in work with dogs (Ellman et al., 1980; Buchta et al., 1982) that the initial damage to the kidney after injection of ethanol occurs to the lamina tara externa of the glomerular capillaries as well as to the ultrastructure of the gIomerular endothelial, epithelial and mesangial cells. Main renal artery thrombosis is felt to be a secondary, delayed effect due to the lack of blood flow through an already irreversibly devitalised organ. This is borne out in clinical practice: the immediate post-embolisation arteriogram, and in particular the patency of the main renal artery, being a poor guide to the amount of eventual infarction. It must be remembered, therefore, that the effect of ethanol is primarily chemical
and that some time should elapse before nephrectomy if maximum infarction is to be obtained. A minimum of 7 days is suggested. In the absence of any details of technique, in particular the time between embolisation and harvesting the kidneys and the amount and rate of injection of ethanol used, I cannot comment on why Dr Jeans was only able to obtain patchy infarction in rats. This is certainly contrary to the published work in animal models. I would welcome a prospective, randomised trial to assess the efficacy of pre-operative embolisation of hypernephromas. Because of the varying techniques of embolisation that are likely to be used, and the inevitably subjective assessment by the surgeons of the ease of nephrectomy, as well as the large differences that occur in the vascularity and prognosis of these tumours, I think the results may not be too easy to ifiterpret. We continue to use ethanol injected through a balloon catheter routinely for embolisation pre-operatively and remain impressed by the ease, safety and efficacy of the technique. I. P. WELLS Radiodiagnostic Department Derriford Hospital Plymouth References
Buchta, K., Sands, J., Rosenkrantz, H. & Roche, W. D. (1982). Early mechanism of action of arterially infused alcohol U.S.P. in renal devitalization. Radiology, 145, 45-48. Ellman, B. A., Green, C. E., Eigenbrodte, E., Garriot, J. C. & Curry, T. S. (1980). Renal infarction with absolute ethanol. Investigative Radiology, 15, 318-322. SIR- Dr Jeans is quite right to point out that our paper did not discuss the benefits of pre-operative embolisation of renal carcinoma in any depth and dealt largely with technical aspects of the procedure. The aim of our paper was to describe and document a technique which could be relied upon to produce tumour infarction in excess of 50% as it seems likely that the therapeutic benefit would depend upon the extent of tumour infarction. The immediate benefits of pre-operative embolisation are already well established and we felt that we had little to add to previously published papers. There is little doubt that the procedure reduces the vascularity of renal carcinomas and makes subsequent nephrectomy technically easier (Mee and Heap, 1978; Giuliani et al., 1981; Wallace et al., 1981), that it can shorten the time required for nephrectomy (Hlava et al., 1976) and that it often reduces the operative blood loss (Singsaas et al., 1979). Dr Jeans has pointed out that renal artery embolisation is often distressing to the patient and we would agree that the potential therapeutic benefit should be weighed against the possible morbidity. In our series, the 'post-infarcfion' syndrome of renal pain, fever and nausea occurred in most patients and 17 required narcotic analgesics for adequate relief. There were two serious complications: one patient developed occlusion of the right anterior tibial artery 4h after embolisation, but the foot returned to normal 24h later after an exploratory operation and treatment with intravenous heparin (Kaisary et al., 1982) and another patient developed renal failure 3 days after the procedure and required dialysis before recovering completely. We agree that the important question is the effect of the procedure on patient survival, but we were unable to draw any useful conclusions from our 30 patients at the time we submitted the paper. Our figures showed that survival was longer in patients with localised disease (Stages 1 and 2; Robson et al. (1969)) than in patients with widespread disease (Stages 3 and 4) but this observation has often been made in the past. The course of two of the four patients with radiological evidence of pulmonary metastases at the time of embolisation and nephrectomy was unexpected and has been described more fully in another paper