Retroperitoneal Lymph Node Dissection for Wilms' Tumor By Lester W. Martin, Donald P. Schaffner, Joseph A. Cox, Jens G. Rosenkrantz, and William R. Richardson Cincinnati, Ohio 9 N e p h r e c t o m y for Wilms' t u m o r was performed on 58 patients over a 20-yr period, and retroperitoneal lymphadenectomy was performed on 35 w h o presented w i t h no demonstrable metastases. The survival rate was 1 0 0 % for 19 clinical group I patients with negative nodes. Positive nodes in 9 instances led to 5 long-term survivors and significantly influenced staging as a guide for f u r t h e r therapy. INDEX WORDS: Wilms" tumor.
E T R O P E R I T O N E A L lymph node dissection in addition to nephrectomy for Witms" tumor is advocated with the assumption that local lymphatic metastases may sometimes occur prior to hematogenous spread. The role of regional lymph node dissection along with nephrectomy for Wilms' tumor was demonstrated in our initial 10-yr experience in which we encountered a 35% incidence of metastases to the removed nodes in 20 patients with no demonstrable distant metastases.' The practice has been continued for a total of 20 yr and the entire experience constitutes the basis for this report.
R
RETROPERITONEAL LYMPH NODE ANATOMY
The lymphatics of the renal parenchyma and fibrous capsule are in continutiy but do not communicate with the perirenal lymphatics. Anterior, middle and posterior main lymphatic trunks emerge from renal pedicles on each side and are located in front, between, and behind the renal vessels. 2 On the left side, the anterior trunk terminates (I) in the lateroaortic nodes located between the renal and inferior mesenteric arteries, and (2) in nodes at the junction of the renal vein with the From the Division of Pediatric Surgery of The Children's Hospital and the Department of Surgery, The College of Medicine, The University of Cincinnati. Cincinnati, Ohio. Presented before the lOtb Annual Meeting of the American Pediatric Surgical Association, Los Angeles. California, March 25-28, 1979. Address reprint requests to Donald P. Schaffner, M.D., Department of Surgery. The College of Medicine, University of Cincinnati, Cincinnati, Ohio. 9 1979 by Grune & Stratton, Inc. 002~ 3468/79/1406-0014501.00/0 704
adrenal and spermatic veins. The left middle trunks terminate in the lateroaortic and suprarenal junction nodes. The left posterior trunks drain into the lateroaortic nodes near the origin of the renal artery. On the right side, the lymphatics embrace the vena cava to reach the aorta. The right anterior trunk courses anterior to the vena cava to reach the lateroaortic nodes. Additional branches of the anterior trunk may terminate below the renal vein or anterior to the vena cava. The right middle trunks course between the renal vessels with intermediate nodes encountered before terminating in the lateroaortic nodes. The right posterior trunks course behind the vena cava to the lateroaortic lymph nodes located between the levels of origin of the renal and inferior mesenteric arteries. Since the left renal lymphatic drainage is located on the left side of the aorta, a left retroperitoneal lymph node dissection includes all the nodes from the anterior midline of aorta to the posterior midline of aorta extending from the lilac bifurcation to the diaphragm. Since the right renal lymphatic drainage encircles the vena cava to reach the right half of the aorta, a right retroperitoneal lymph node dissection must remove all the nodes about the circumference of the vena cava and the right half of the aorta from the iliac bifurcation to the liver (Fig. 1). TECHNIQUE OF LYMPH NODE DISSECTION
For nephrectomy with removal of a Wilms' tumor and regional lymph nodes, we prefer a long transverse supraumbilical incision extending from flank to flank. After completion of the nephrectomy, the ipsilateral periaortic nodes and adventitial tissue from the crura of the diaphragm to the iliac bifurcation are removed en bloc. On the left side, the splenic attachments to the diaphragm are divided and the spleen and pancreas displaced medially, exposing the crura of the diaphragm. The inferior mesenteric artery is identified and preserved. All the ipsilateral lymph node-bearing tissue is removed from the anterior to posteJournal of Pediatric Surgery, Vol. 14, No. 6 (December), 1979
NODE DISSECTION FOR WILMS' TUMOR
705
Table 1. Wilms" Tumor 1 9 5 9 - 1 9 7 9 35 Lymph Node Dissections
!
No. Patients
Nodes negative (group I) Nodes negative (all groups) Nodes positive Total
Total
Alive
Percent Survival
19 26 9 35
19 22 5 27
1O0 85 55 77
MATERIALS
Fig. 1. Diagram of lymphatic drainage of kidneys w i t h location of regional lymph nodes. Dotted lines indicate extent of recommended dissection w h i c h should be carried t o the midline of the aorta from either the right or t h e left side.
rior a o r t i c m i d l i n e f r o m t h e d i a p h r a g m to below t h e a o r t i c b i f u r c a t i o n . T h e s t u m p of the renal a r t e r y is ligated flush with the a o r t a and r e m o v e d a l o n g w i t h a n y a t t a c h e d nodes and a d v e n t i t i a . T h e left s p e r m a t i c vein and the s t u m p of the renal vein a r e likewise l i g a t e d ; the latter, flush w i t h the v e n a c a v a and r e m o v e d with the a t t a c h e d nodes. T h e c o m p l e t e d dissection leaves the left h a l f of the a o r t a c o m p l e t e l y s k e l e t o n i z e d f r o m the d i a p h r a g m to below the aortic bifurcation. O n the right side, the field of dissection i n c l u d e s all the l y m p h node b e a r i n g tissue a b o u t the c i r c u m f e r e n c e of the v e n a c a v a and f r o m the r i g h t h a l f of the aorta. L e n g t h w i s e , the field e x t e n d s f r o m the liver to t h e iliac b i f u r c a t i o n . It is i m p o r t a n t to r e m o v e all a d v e n t i t i a a n d nodes f r o m a b o u t t h e left renal vein as far left as the m i d l i n e of the aorta. T h e c o m p l e t e d dissection leaves the v e n a c a v a c o m p l e t e l y s k e l e t o n i z e d and t h e r i g h t h a l f of the a o r t a free of a n y a d v e n t i t i a . D u r i n g the c o u r s e of the l y m p h node dissection on e i t h e r side, s e l e c t e d s m a l l l u m b a r vessels distal to the renal vessels m a y , if n e c e s s a r y , be sacrificed, b u t w i t h care, v i r t u a l l y all of t h e m can be p r e s e r v e d . T h e l u m b a r s y m p a t h e t i c c h a i n and i l e o - i n g u i n a l nerves are p r e s e r v e d . C a r e m u s t be t a k e n to l i g a t e all s e v e r e d l y m p h a t i c c h a n n e l s , p a r t i c u l a r l y at the m o s t distal e x t e n t of the dissection. It is our p r a c t i c e to l i g a t e all a d v e n t i t i a distally prior to its t r a n s e c t i o n .
For the past 20 years, it has been our policy to perform a retroperitoneal lymph node dissection in association with nephrectomy for Wilms' tumor, providing there are no demonstrable distant metastases. Of 58 patients, a lymph node dissection was performed on 35. Metastatic tumor was demonstrated in the removed nodes in nine (26%) of the 35 patients. Five of the nine patients with positive nodes are alive and free of evident tumor eight or more years following operation. All of the patients have been followed at least at yearly intervals and treated with systemic chemotherapy and postoperative radiation therapy except for one clinical group 1 patient, 6 mo of age, who did not receive radiation therapy. Nineteen of our 58 (33%) patients have had tumor limited to the kidney (group 1) with a I00~ survival rate (Table 1). The incidence of demonstrable metastasis of bilateral tumors was 41% with a 29% survival rate. There were no local abdominal recurrences in the group except for one patient early in the series who died of a second tumor of the opposite kidney ~ that had not been examined at operation. The only complication of node dissection remains the one instance of operative injury to the aorta previously described in our 1959 to 1969 series. Her defect was repaired with an uneventful recovery. She has hypertension thought to be related to renal fibrosis demonstrated by renal biopsy. Chylous ascites following retroperitoneal lymphadenectomy for Wilms' tumor was reported by Herz4 in one patient, but none has occurred in our series. Of our 21 patients since 1969 with group II, Ill, and 1V involvement, 3 died of hepatitis, pneumonia, and thrombocytopenia possibly related to postoperative irradiation and systemic chemotherapy, but had no evidence of residual tumor at autopsy. Other complications have included resolved hepatitis in three patients, exploratory laparotomy with lysis of adhesions for small bowel obstruction in 4 patients, and mild scoliosis in 3 patients. DISCUSSION
Complete surgical excision remains the p r e f e r r e d t r e a t m e n t of W i l m s ' t u m o r 5 and, in l o c a l i z e d disease, yields results t h a t a r e consist e n t l y s u p e r i o r to any o t h e r f o r m of t h e r a p y . O u r e x p e r i e n c e i n d i c a t e s t h a t in o n e - f o u r t h of p a t i e n t s , r e g i o n a l l y m p h node m e t a s t a s i s has o c c u r r e d prior to clinically d e m o n s t r a b l e d i s t a n t m e t a s t a s e s . It w o u l d a p p e a r to be t h e r a p e u t i -
706
MARTIN ET AL.
cally beneficial, therefore, to remove the nodes in such instances. Our experience of five long-term survivors out of nine with positive nodes is to be compared with results that can be achieved through the various combinations of modern chemotherapy and cobalt radiation techniques. 6'7 Comparison is difficult because of several variables. Three of our four deaths occurred after more than 2 yr following operation, yet many current reports are based on only a 2 yr follow-up. All of our deaths were in clinical group II-V patients with a small number in each group. The preoperative search for distant metastasis has improved in recent years through refinement of diagnostic techniques such as computerized tomography, radioactive scans, and ultrasound studies, but still is not completely accurate. The clinical staging may be influenced by the results of node dissection. Four of our patients
would have been considered clinical group I if node dissection had not been performed. SUMMARY
Of 58 patients with Wilms' tumor over a 20-yr period, retroperitoneal lymph node dissection was performed on all 35 who presented with no demonstrable distant metastases. Lymph nodes were positive for tumor in 9 instances, 5 of whom survive tumor free for 8 or more years following operation. Four patients would have been erroneously staged as clinical group I without the information obtained from node dissection. Of 19 patients of clinical group I with negative nodes, all survive. Retroperitoneal lymph node dissection appears to be of value for clinical staging as well as for a more complete removal of the malignant process.
REFERENCES 1. Martin LW, Reyes PM: An evaluation of 10 years' experience with retroperitoneal lymph node dissection for Wilms' tumor. J Pediatr Surg 4:683-687, 1969 2. Rouviere H: Anatomy of the Human Lymphatic System. Ann Arbor, Mich., Edwards Brothers Inc, 1938 3. Martin LW, Kloecher R J: Bilateral nephroblastoma (Wilms' tumor) of the kidney. Pediatrics 28:101 -106, 1961 4. Herz J, Shapiro SR, Konrad P, et al: Chylous ascites following retroperitoneal lymphadenectomy. Cancer 42:349352, 1978
5. Gross RE: Embryoma of the kidney (Wilms' tumor), in The Surgery of Infancy and Childhood. Philadelphia, Saunders, 1953, pp 588-605 6. D'Angio G J, Evans AE, Breslow N, et al: The treatment of Wilms' tumor: Results of the National Wilms' Tumor Study. Cancer 38:633-646, 1976 7. Leape LL, Breslow N, Bishop HC: The surgical treatment of Wilms' tumor: Results of the National Wilms' Tumor Study. Ann Surg 187: 351-356, 1978
Discussion L. L. Leape (Boston): Two years ago, we proposed a prospective study of retroperitoneal lymph node dissection for Wilms' tumor. The study was decided against because the statisticians said we couldn't prove that it made any difference! The problem is that the treatment of Wilms' tumor has become too good. We can now expect an 85% disease-free survival rate in patients in group I1 or III. This is the standard against which any new treatment must be judged. In the National Wilms' Tumor Study, if the nodes were resected it didn't make any difference. This was an uncontrolled study, however. I would ask Dr. Martin if, in the absence of controls, he can show a difference? There are two important unanswered questions. One, can we improve survival by node dissection? It is going to be very difficult to tell that
without a controlled study. Two, will node dissection help in staging? The relevance of that has to do with treatment because patients with Stage I disease will not need radiotherapy and will need a shorter course of chemotherapy. Being absolutely certain that those nodes are negative, i.e., that the patient truly is stage I, is very important. Maybe the next Wilms' Tumor Study will answer that. J. L. Grosfeld (Indianapolis): I had the privilege of hearing Dr. Martin present his initial data on this subject 10 yr ago at the BAPS meeting in Dublin, Ireland. I'm pleased to see that he's continued this work as it yields some valuable historical information concerning lymph node dissection in Wilms' tumor. A 25% incidence of lymph node metastases was noted. This is important both for staging and as a
NODE DISSECTION FOR WILMS' TUMOR
prognostic factor as none of the patients with negative nodes died. I have a number of question for the authors: In the five patients with nodal involvement who lived, was survival related to lymph node removal, therapy, or the histology of the tumor? Did the survivors have tumors with favorable histology and those who died unfavorable histology (anaplastic or sarcomatous tumors)? Should patients with lymph node metastases receive more aggressive treatment with 3 or 4 chemotherapeutic agents to try and improve their 55% survival rate? Would the authors recommend a bilateral lymph node dissection in children with synchronous bilateral Wilms' tumor? A. P. M. Kumar (Memphis): In 150 patients with Wilms' tumor, we have not performed the node dissection like Dr. Schaffner showed here. In recent years, since the incorporation of adriamycin to the chemotherapy schedule in Stage l lI disease where we do thorough sampling of nodes above and below the hilum we have 96% relapse-free survival and 88% tumor-free survival in our patients. Therefore, whether we do this node dissection or not, i believe you can come up with good survival rates. And, currently, the discussion is, can we minimize the therapy in Wilms" tumor'? Because the results are so good, maybe the incorporation of this node dissection would minimize the use of the drugs and radiation. If so, it will be good contribution to this combined management. A. A. De Lorimier (San Francisco): The histology of these cases should be clarified as to the favorable and unfavorable types for compari-
707
son. Nine out of ten children with Wilms' tumor today will have favorable histology. In those, the survival rate is better than 90% with or without retroperitoneal node dissection. The mortality is in those children with unfavorable histology and this is the area where lymph node dissection may make a difference. It is not clear whether chemotherapy or radiotherapy influences survival in those children. However, with one child in ten having unfavorable histology, it may be difficult to gain enough numbers to identify the role of retroperitoneal dissection. As we discuss Wilms' tumor nowadays we really have to report the results in terms of the histologic types. D. P. SchafJher (closure): The question by Dr. Leape concerning the means by which we can improve our survival and whether or not we can show that this, the retroperitoneal lymph node dissection in association with a nephrectomy will accomplish this. 1 can only suggest that it be randomized in the national Wilms' tumor study for further study. Our data suggest that it does influence our ability to clinically stage the patients and potentially allow more complete removal of the malignant process. The question of survival in the five patients of the nine who had lymph node dissection; there were multiple variables there and whether or not those had more favorable or less favorable histology I can't answer. Dr. Kumar raises the point that our multimodality therapy is improving the stage III survival, and that the clinical staging is allowing us to tailor that treatment more appropriately to the patients" needs and minimize their morbidity associated with that therapy.
E T R O P E R I T O N E A L lymph node dissection in addition to nephrectomy for Witms" tumor is advocated with the assumption that local lymphatic metastases may sometimes occur prior to hematogenous spread. The role of regional lymph node dissection along with nephrectomy for Wilms' tumor was demonstrated in our initial 10-yr experience in which we encountered a 35% incidence of metastases to the removed nodes in 20 patients with no demonstrable distant metastases.' The practice has been continued for a total of 20 yr and the entire experience constitutes the basis for this report.
R
RETROPERITONEAL LYMPH NODE ANATOMY
The lymphatics of the renal parenchyma and fibrous capsule are in continutiy but do not communicate with the perirenal lymphatics. Anterior, middle and posterior main lymphatic trunks emerge from renal pedicles on each side and are located in front, between, and behind the renal vessels. 2 On the left side, the anterior trunk terminates (I) in the lateroaortic nodes located between the renal and inferior mesenteric arteries, and (2) in nodes at the junction of the renal vein with the From the Division of Pediatric Surgery of The Children's Hospital and the Department of Surgery, The College of Medicine, The University of Cincinnati. Cincinnati, Ohio. Presented before the lOtb Annual Meeting of the American Pediatric Surgical Association, Los Angeles. California, March 25-28, 1979. Address reprint requests to Donald P. Schaffner, M.D., Department of Surgery. The College of Medicine, University of Cincinnati, Cincinnati, Ohio. 9 1979 by Grune & Stratton, Inc. 002~ 3468/79/1406-0014501.00/0 704
adrenal and spermatic veins. The left middle trunks terminate in the lateroaortic and suprarenal junction nodes. The left posterior trunks drain into the lateroaortic nodes near the origin of the renal artery. On the right side, the lymphatics embrace the vena cava to reach the aorta. The right anterior trunk courses anterior to the vena cava to reach the lateroaortic nodes. Additional branches of the anterior trunk may terminate below the renal vein or anterior to the vena cava. The right middle trunks course between the renal vessels with intermediate nodes encountered before terminating in the lateroaortic nodes. The right posterior trunks course behind the vena cava to the lateroaortic lymph nodes located between the levels of origin of the renal and inferior mesenteric arteries. Since the left renal lymphatic drainage is located on the left side of the aorta, a left retroperitoneal lymph node dissection includes all the nodes from the anterior midline of aorta to the posterior midline of aorta extending from the lilac bifurcation to the diaphragm. Since the right renal lymphatic drainage encircles the vena cava to reach the right half of the aorta, a right retroperitoneal lymph node dissection must remove all the nodes about the circumference of the vena cava and the right half of the aorta from the iliac bifurcation to the liver (Fig. 1). TECHNIQUE OF LYMPH NODE DISSECTION
For nephrectomy with removal of a Wilms' tumor and regional lymph nodes, we prefer a long transverse supraumbilical incision extending from flank to flank. After completion of the nephrectomy, the ipsilateral periaortic nodes and adventitial tissue from the crura of the diaphragm to the iliac bifurcation are removed en bloc. On the left side, the splenic attachments to the diaphragm are divided and the spleen and pancreas displaced medially, exposing the crura of the diaphragm. The inferior mesenteric artery is identified and preserved. All the ipsilateral lymph node-bearing tissue is removed from the anterior to posteJournal of Pediatric Surgery, Vol. 14, No. 6 (December), 1979
NODE DISSECTION FOR WILMS' TUMOR
705
Table 1. Wilms" Tumor 1 9 5 9 - 1 9 7 9 35 Lymph Node Dissections
!
No. Patients
Nodes negative (group I) Nodes negative (all groups) Nodes positive Total
Total
Alive
Percent Survival
19 26 9 35
19 22 5 27
1O0 85 55 77
MATERIALS
Fig. 1. Diagram of lymphatic drainage of kidneys w i t h location of regional lymph nodes. Dotted lines indicate extent of recommended dissection w h i c h should be carried t o the midline of the aorta from either the right or t h e left side.
rior a o r t i c m i d l i n e f r o m t h e d i a p h r a g m to below t h e a o r t i c b i f u r c a t i o n . T h e s t u m p of the renal a r t e r y is ligated flush with the a o r t a and r e m o v e d a l o n g w i t h a n y a t t a c h e d nodes and a d v e n t i t i a . T h e left s p e r m a t i c vein and the s t u m p of the renal vein a r e likewise l i g a t e d ; the latter, flush w i t h the v e n a c a v a and r e m o v e d with the a t t a c h e d nodes. T h e c o m p l e t e d dissection leaves the left h a l f of the a o r t a c o m p l e t e l y s k e l e t o n i z e d f r o m the d i a p h r a g m to below the aortic bifurcation. O n the right side, the field of dissection i n c l u d e s all the l y m p h node b e a r i n g tissue a b o u t the c i r c u m f e r e n c e of the v e n a c a v a and f r o m the r i g h t h a l f of the aorta. L e n g t h w i s e , the field e x t e n d s f r o m the liver to t h e iliac b i f u r c a t i o n . It is i m p o r t a n t to r e m o v e all a d v e n t i t i a a n d nodes f r o m a b o u t t h e left renal vein as far left as the m i d l i n e of the aorta. T h e c o m p l e t e d dissection leaves the v e n a c a v a c o m p l e t e l y s k e l e t o n i z e d and t h e r i g h t h a l f of the a o r t a free of a n y a d v e n t i t i a . D u r i n g the c o u r s e of the l y m p h node dissection on e i t h e r side, s e l e c t e d s m a l l l u m b a r vessels distal to the renal vessels m a y , if n e c e s s a r y , be sacrificed, b u t w i t h care, v i r t u a l l y all of t h e m can be p r e s e r v e d . T h e l u m b a r s y m p a t h e t i c c h a i n and i l e o - i n g u i n a l nerves are p r e s e r v e d . C a r e m u s t be t a k e n to l i g a t e all s e v e r e d l y m p h a t i c c h a n n e l s , p a r t i c u l a r l y at the m o s t distal e x t e n t of the dissection. It is our p r a c t i c e to l i g a t e all a d v e n t i t i a distally prior to its t r a n s e c t i o n .
For the past 20 years, it has been our policy to perform a retroperitoneal lymph node dissection in association with nephrectomy for Wilms' tumor, providing there are no demonstrable distant metastases. Of 58 patients, a lymph node dissection was performed on 35. Metastatic tumor was demonstrated in the removed nodes in nine (26%) of the 35 patients. Five of the nine patients with positive nodes are alive and free of evident tumor eight or more years following operation. All of the patients have been followed at least at yearly intervals and treated with systemic chemotherapy and postoperative radiation therapy except for one clinical group 1 patient, 6 mo of age, who did not receive radiation therapy. Nineteen of our 58 (33%) patients have had tumor limited to the kidney (group 1) with a I00~ survival rate (Table 1). The incidence of demonstrable metastasis of bilateral tumors was 41% with a 29% survival rate. There were no local abdominal recurrences in the group except for one patient early in the series who died of a second tumor of the opposite kidney ~ that had not been examined at operation. The only complication of node dissection remains the one instance of operative injury to the aorta previously described in our 1959 to 1969 series. Her defect was repaired with an uneventful recovery. She has hypertension thought to be related to renal fibrosis demonstrated by renal biopsy. Chylous ascites following retroperitoneal lymphadenectomy for Wilms' tumor was reported by Herz4 in one patient, but none has occurred in our series. Of our 21 patients since 1969 with group II, Ill, and 1V involvement, 3 died of hepatitis, pneumonia, and thrombocytopenia possibly related to postoperative irradiation and systemic chemotherapy, but had no evidence of residual tumor at autopsy. Other complications have included resolved hepatitis in three patients, exploratory laparotomy with lysis of adhesions for small bowel obstruction in 4 patients, and mild scoliosis in 3 patients. DISCUSSION
Complete surgical excision remains the p r e f e r r e d t r e a t m e n t of W i l m s ' t u m o r 5 and, in l o c a l i z e d disease, yields results t h a t a r e consist e n t l y s u p e r i o r to any o t h e r f o r m of t h e r a p y . O u r e x p e r i e n c e i n d i c a t e s t h a t in o n e - f o u r t h of p a t i e n t s , r e g i o n a l l y m p h node m e t a s t a s i s has o c c u r r e d prior to clinically d e m o n s t r a b l e d i s t a n t m e t a s t a s e s . It w o u l d a p p e a r to be t h e r a p e u t i -
706
MARTIN ET AL.
cally beneficial, therefore, to remove the nodes in such instances. Our experience of five long-term survivors out of nine with positive nodes is to be compared with results that can be achieved through the various combinations of modern chemotherapy and cobalt radiation techniques. 6'7 Comparison is difficult because of several variables. Three of our four deaths occurred after more than 2 yr following operation, yet many current reports are based on only a 2 yr follow-up. All of our deaths were in clinical group II-V patients with a small number in each group. The preoperative search for distant metastasis has improved in recent years through refinement of diagnostic techniques such as computerized tomography, radioactive scans, and ultrasound studies, but still is not completely accurate. The clinical staging may be influenced by the results of node dissection. Four of our patients
would have been considered clinical group I if node dissection had not been performed. SUMMARY
Of 58 patients with Wilms' tumor over a 20-yr period, retroperitoneal lymph node dissection was performed on all 35 who presented with no demonstrable distant metastases. Lymph nodes were positive for tumor in 9 instances, 5 of whom survive tumor free for 8 or more years following operation. Four patients would have been erroneously staged as clinical group I without the information obtained from node dissection. Of 19 patients of clinical group I with negative nodes, all survive. Retroperitoneal lymph node dissection appears to be of value for clinical staging as well as for a more complete removal of the malignant process.
REFERENCES 1. Martin LW, Reyes PM: An evaluation of 10 years' experience with retroperitoneal lymph node dissection for Wilms' tumor. J Pediatr Surg 4:683-687, 1969 2. Rouviere H: Anatomy of the Human Lymphatic System. Ann Arbor, Mich., Edwards Brothers Inc, 1938 3. Martin LW, Kloecher R J: Bilateral nephroblastoma (Wilms' tumor) of the kidney. Pediatrics 28:101 -106, 1961 4. Herz J, Shapiro SR, Konrad P, et al: Chylous ascites following retroperitoneal lymphadenectomy. Cancer 42:349352, 1978
5. Gross RE: Embryoma of the kidney (Wilms' tumor), in The Surgery of Infancy and Childhood. Philadelphia, Saunders, 1953, pp 588-605 6. D'Angio G J, Evans AE, Breslow N, et al: The treatment of Wilms' tumor: Results of the National Wilms' Tumor Study. Cancer 38:633-646, 1976 7. Leape LL, Breslow N, Bishop HC: The surgical treatment of Wilms' tumor: Results of the National Wilms' Tumor Study. Ann Surg 187: 351-356, 1978
Discussion L. L. Leape (Boston): Two years ago, we proposed a prospective study of retroperitoneal lymph node dissection for Wilms' tumor. The study was decided against because the statisticians said we couldn't prove that it made any difference! The problem is that the treatment of Wilms' tumor has become too good. We can now expect an 85% disease-free survival rate in patients in group I1 or III. This is the standard against which any new treatment must be judged. In the National Wilms' Tumor Study, if the nodes were resected it didn't make any difference. This was an uncontrolled study, however. I would ask Dr. Martin if, in the absence of controls, he can show a difference? There are two important unanswered questions. One, can we improve survival by node dissection? It is going to be very difficult to tell that
without a controlled study. Two, will node dissection help in staging? The relevance of that has to do with treatment because patients with Stage I disease will not need radiotherapy and will need a shorter course of chemotherapy. Being absolutely certain that those nodes are negative, i.e., that the patient truly is stage I, is very important. Maybe the next Wilms' Tumor Study will answer that. J. L. Grosfeld (Indianapolis): I had the privilege of hearing Dr. Martin present his initial data on this subject 10 yr ago at the BAPS meeting in Dublin, Ireland. I'm pleased to see that he's continued this work as it yields some valuable historical information concerning lymph node dissection in Wilms' tumor. A 25% incidence of lymph node metastases was noted. This is important both for staging and as a
NODE DISSECTION FOR WILMS' TUMOR
prognostic factor as none of the patients with negative nodes died. I have a number of question for the authors: In the five patients with nodal involvement who lived, was survival related to lymph node removal, therapy, or the histology of the tumor? Did the survivors have tumors with favorable histology and those who died unfavorable histology (anaplastic or sarcomatous tumors)? Should patients with lymph node metastases receive more aggressive treatment with 3 or 4 chemotherapeutic agents to try and improve their 55% survival rate? Would the authors recommend a bilateral lymph node dissection in children with synchronous bilateral Wilms' tumor? A. P. M. Kumar (Memphis): In 150 patients with Wilms' tumor, we have not performed the node dissection like Dr. Schaffner showed here. In recent years, since the incorporation of adriamycin to the chemotherapy schedule in Stage l lI disease where we do thorough sampling of nodes above and below the hilum we have 96% relapse-free survival and 88% tumor-free survival in our patients. Therefore, whether we do this node dissection or not, i believe you can come up with good survival rates. And, currently, the discussion is, can we minimize the therapy in Wilms" tumor'? Because the results are so good, maybe the incorporation of this node dissection would minimize the use of the drugs and radiation. If so, it will be good contribution to this combined management. A. A. De Lorimier (San Francisco): The histology of these cases should be clarified as to the favorable and unfavorable types for compari-
707
son. Nine out of ten children with Wilms' tumor today will have favorable histology. In those, the survival rate is better than 90% with or without retroperitoneal node dissection. The mortality is in those children with unfavorable histology and this is the area where lymph node dissection may make a difference. It is not clear whether chemotherapy or radiotherapy influences survival in those children. However, with one child in ten having unfavorable histology, it may be difficult to gain enough numbers to identify the role of retroperitoneal dissection. As we discuss Wilms' tumor nowadays we really have to report the results in terms of the histologic types. D. P. SchafJher (closure): The question by Dr. Leape concerning the means by which we can improve our survival and whether or not we can show that this, the retroperitoneal lymph node dissection in association with a nephrectomy will accomplish this. 1 can only suggest that it be randomized in the national Wilms' tumor study for further study. Our data suggest that it does influence our ability to clinically stage the patients and potentially allow more complete removal of the malignant process. The question of survival in the five patients of the nine who had lymph node dissection; there were multiple variables there and whether or not those had more favorable or less favorable histology I can't answer. Dr. Kumar raises the point that our multimodality therapy is improving the stage III survival, and that the clinical staging is allowing us to tailor that treatment more appropriately to the patients" needs and minimize their morbidity associated with that therapy.
