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CancerGuide: Special Kidney Cancer Section
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The Atzpodien Regimen: IL-2, Interferon, and 5-FU
This complex triple drug cocktail is a standard treatment in Germany where it was developed by Dr. Jens Atzpodien and colleagues. It may be used in other European countries as well. It doesn't seem to be widely used in the United States. The treatment is mostly outpatient though a few studies report hospitalizing patients for the most intense part of the treatment. Dr. Atzpodien and several others have reported high response rates - higher than for IL-2 alone with long term survivals which look roughly similar to high dose IL-2. This, along with it being standard treatment in parts of Europe, makes it important and worth covering. 5-FU (5-Fluorouracil) is actually an old and well known chemotherapy drug. Although RCC doesn't respond to chemotherapy, Interferon has been combined with 5-FU in the treatment of other cancers. Still, I don't know why 5-FU might add to the effectiveness of immunotherapy. To make things complicated, the Atzpodien protocol is by no means the only combination using these three drugs that have been tried. Some protocols involving these drugs are pretty close to Dr. Atzpodien's and others are quite different. I am focusing on the Atzpodien protocol because there seems to be the most data for it and because other combinations involving the three drugs don't have better results (and some had worse results). Finally, there are some very interesting results with the triple drug therapy plus a drug related to Vitamin A, 13-Cis-Retinoic Acid. It appears that this four drug combination might have significantly have better survival although there isn't enough data to make this a certainty. If high dose IL-2 isn't an option, I think this four drug therapy is worth considering. The Atzpodien Triple Drug Regimen DefinedThis is a remarkably complex protocol and I can't explain how Dr. Atzpodien and colleagues came up with it. The following overview will help organize it in your mind:
Click Here For A Diagram of the Protocol The DataThe Triple Drug TherapyThere are many ways these three drugs can be combined and most reviews seem to lump all studies using these three drugs together regardless of the protocol. I do not agree with this because I think dose and schedule can be critically important, and so I think concentrating on studies which used Atzpodien's actual protocol gives you a clearer signal.
On the whole, although results vary, my impression is that the Atzpodien therapy tends to get a higher response rate than other IL-2 therapies, inpatient or outpatient. The big question is whether this translates into improved survival. See my comments in the conclusions section for more on this. IL-2, Interferon, 5-FU, and 13-Cis-Retinoic AcidThis covers the Atzpodien triple drug therapy plus a fourth drug called 13-Cis-Retinoic Acid (13-CRA). This variant is important because the data suggest (though as usual don't prove) that adding 13-CRA may significantly improve the results of the triple drug therapy. Consistent with my approach to the triple drug combination, I am only covering 13-CRA in combination with Atzpodien's triple drug protocol. 13-CRA is an oral FDA approved prescription drug used to treat severe acne. The generic name is "Isotretinoin" and Roche markets it under the brand name "Accutane". 13-CRA is a chemical derivative of Vitamin A and may inhibit cancer cell proliferation, act as a "differentiating agent", and make the cells more visible to the immune system. 13-CRA by itself and with Interferon have been used in cancer treatment. 13- CRA alone has been used to prevent second cancers in head and neck cancer. More importantly, 13-CRA combined with interferon has been tested in RCC. An initial phase II study had very promising results [Motzer 1995] but a a decent sized randomized trial of Interferon versus Interferon + 13-CRA didn't confirm any survival benefit [Motzer 2000] although there were still some hints of synergy for the combination. Overall, this suggests adding 13-CRA to the triple drug therapy might be useful. The primary side effects of 13-CRA are dry skin and mucous membranes and elevated blood triglycerides. Over the long term, elevated triglycerides would be a risk for heart disease, but I doubt serious damage is done with short term treatment. In any event, if you have metastatic renal cell carcinoma, long term risks of heart disease are not your biggest worry. For more details on 13-CRA side-effects, including some rare serious side effects, read the official prescribing information on Roche's Accutane page. Note that the doses used in these clinical trials are the same as the dose prescribed for acne.
Response rates certainly don't appear higher with 13-CRA than without it. The median survivals tend to be on the upper end of what's been seen with the triple drug therapy, especially from Atzpodien 2002 but overall, it's hard to say they're really different. Atzpodien 2002a is actually a randomized study which compared triple drug therapy to triple drug therapy + 13-CRA to Interferon + Vinblastine. Response rates were very similar for triple drug therapy with or without 13-CRA. This meeting abstract doesn't have enough information to assess whether survival is better with 13-CRA. Fortunately, this important study will be published soon (Jens Atzpodien, MD personal communication January 2004). Roigas 2003, is actually a retrospective comparison between patients treated with the triple drug therapy and with triple drug therapy + 13-CRA at about the same time. They found no sign of any improvement with the addition of 13-CRA, although the response rates they got overall still weren't bad. The study is fairly small and not randomized. At present, there is really only one piece of evidence which favors adding 13-CRA, and it's striking, but still quite uncertain. This is from Dr. Atzpodien's 2002 long term efficacy study of three different regimens where patients who got 13-CRA had strikingly better survival. Dr. Atzpodien's 2002 Long-Term StudyIn 2002 Dr. Atzpodien and colleagues reported a huge study of his triple drug regimen and two variants with as much as 13 years of follow-up in some patients [Atzpodien 2002]. This study is so important, it's worth covering in detail. The study reports on 443 patients treated with three different IL-2 regimens in sequential trials. The treatments are IL-2 and Interferon alone, The Atzpodien triple drug regimen, and the Atzpodien triple drug regimen plus 13-Cis Retinoic Acid. I would have expected this to be a survival update on three previously reported, fully accrued, trials, but they don't explicitly reference any such trials, and I couldn't find any published individual trials by this group that have the right number of patients either. Although they don't specifically say so, it looks like the IL-2 + Interferon and Triple Drug data includes most or all of the patients previously reported in Hanninen 1996 (see my comments under that reference). As far as I can tell, the patients in the four drug trial haven't been reported elsewhere. As a three-in-one report this has some significant deficiencies. They don't report response rates for the individual trials separately - only an overall rate. They also don't report individual response durations so it's more difficult to trace long term survivals to durable response, although they do give statistics which indicate complete responses can be durable as with other IL-2 treatments. I think it's important to trace long term survival with IL-2 treatment to its biological effect as demonstrated by durable responses. Incredibly, they don't say anything at all about side-effects or dose reductions necessitated by side-effects. In the other reports, from their group side-effects of these therapies have been remarkably modest (grade I and II). Atzpodien's IL-2 + Interferon therapy is similar to his triple drug therapy. The first four weeks are exactly the same as the triple drug therapy, including the important intensive therapy weeks (weeks 1 and 4). The second four weeks are different. In the two drug therapy, weeks 5 and 6 are the same as the less intensive IL-2 and Interferon treatment of 2 and 3. Weeks 7 and 8 are rest - no treatment. Click Here For A Diagram of the Atzpodien's IL-2 + Interferon Protocol As with other of Atzpodien's studies, these patients were highly selected. Virtually all had had their kidney out and had minimal or no symptoms. The paper gives no detailed description of how important prognostic factors varied between these groups, although the percentage who'd had their kidney out (almost all), and the percentage with prior systemic therapy are similar in all three groups. It wasn't reported how other prognostic factors such as tumor burden, sites of disease, or presence of symptoms were distributed among the groups. This all makes comparing results with the three treatments riskier! Overall, the study shows long term survival (and probable cure) is possible with any of the treatments. The survival curves (which are reproduced below) are some of the clearest demonstrations of that long flat right tail which is the justification for IL-2 treatment that I have ever seen (which is not to say they are the best long term survival I've seen). One can, as the authors imply, doubt there is any meaning to the differences or similarities between the survival curves for the three treatments because they are from sequential trials rather than a randomized trial, moreover we lack information on how the groups varied as to known prognostic factors. Despite this, these curves are still the best evidence we have about possible differences between these treatments at present. There are two striking things about these curves.
Below are survival curves from the paper demonstrating these points as well as the flat right tail and apparent cures:
My Observations and Conclusions
Annotated ReferencesInterleukin-2- and Interferon Alfa-2a-Based
Immunochemotherapy in Advanced Renal Cell Carcinoma: A Prospectively Randomized
Trial of the German Cooperative Renal Carcinoma Chemoimmunotherapy Group
(DGCIN).
Comment: This is the final report on the three arm randomized trial - I
haven't yet updated this article to reflect that the data show adding 13-CRA
does not improve the results.
Thirteen-year, long-term efficacy of interferon 2alpha
and interleukin 2-based home therapy in patients with advanced renal cell
carcinoma.
Comment: I cover this in detail above.
13cis-retinoic acid, IFN-alpha2a, IL-2 and chemotherapy
in advanced renal cell carcinoma: results of a prospectively randomized trial
of the German Cooperative Renal Carcinoma Chemoimmunotherapy Group (DGCIN)
Proc Am Soc Clin Oncol (ASCO Meeting Abstract)
2002 21 : Abstract 734
[You can find this abstract on the ASCO website (I can't link directly because ASCO won't provide a stable URL)]
Comment: This large randomized study is important. It compares
Atzpodien's triple drug therapy, triple drug therapy + 13-CRA, and Interferon +
Vinblastine. Interferon + Vinblastine is a variant of Interferon therapy which
has gotten results similar to or slightly better than Interferon alone.
Unfortunately, this report is only a meeting abstract and so we are missing the details. Fortunately, the full study should be published soon (Jens Atzpodien, MD personal communication, January 2004). Key Results:
IL-2 in combination with IFN- alpha and 5-FU versus
tamoxifen in metastatic renal cell carcinoma: long-term results of a controlled
randomized clinical trial.
This small randomized trial shows that the Atzpodien triple drug regimen is
better than nothing (actually better than the anti-estrogen drug Tamoxifen
which is inactive). There was a statistically significant difference in favor
of the Atzpodien regimen with survival curves plotted out to six years.
Five year survival was significantly better for the Atzpodien regimen (25%)
compared to Tamoxifen (14%). The trial allowed cross-over for patients on
Tamoxifen whose tumors grew, and about half the Tamoxifen patients crossed over
(we don't know why the others didn't, but they may have been too sick).
Interestingly, the survival curve for the Tamoxifen group shows flattening and
a higher than expected long term survival rate. This is in part due to long
term survival in Tamoxifen patients who crossed over. They also show that among
Tamoxifen patients virtually all had tumor growth by two years (and most much
sooner) while 18% of the Atzpodien regimen patients had no progression at five
years (with a flat curve after about 30 months). Most of these long term
non-progressors were presumably responders.
Comment: Special Note On Ethics: Randomization is ethical where there is no rational basis to believe one treatment in the trial is better than the other. Randomizing patients between a treatment which probably has some efficacy (the IL-2 arm) and one which has been proven to have no efficacy (Tamoxifen) seems totally unethical to me. In this paper the authors describe Tamoxifen as "hardly effective" citing an earlier trial of Tamoxifen[Schomburg 1993]. But this hardly does justice to the conclusion of Schomburg which is that high dose Tamoxifen actually does more harm than good. I was stunned to realize that some of the authors of Schomburg were also authors of this paper, including doctors Atzpodien and Kirchner. One has to presume then they believed their own conclusions about Tamoxifen when they designed this trial. To be fair, this trial did allow crossover to the IL-2 arm on progression of disease, but unfortunately only about half the patients actually crossed over. I presume many were too sick to be eligible after their disease progressed. Therefore, the crossover design did not eliminate the problem of harming patients with a treatment known in advance to be ineffective and harmful. Even the ones who crossed over were harmed by receiving a known harmful treatment while their tumors grew unchecked. As a patient, this trial is a powerful signal that you need to examine randomized trials you are considering in detail to see if the treatment arms are really equally promising. Unfortunately, trust alone is insufficient. At the same time, participation in an ethical randomized trial may help you and help future patients. As Rabbi Hillel famously said, "If I am not for myself, who will be for me? If I am only for myself, what am I?" Disclaimer: I don't mean to imply that Dr. Atzpodien and his colleagues violated any professional standard here. This study was approved by the local ethics board, and was published in a very reputable journal, which wouldn't publish something it considered to be unethical. In my view, this only reinforces the need to be active on your own behalf! 13cis-Retinoic Acid, IFN-Alpha, IL-2 and Chemotherapy in
Advanced Renal Cell Carcinoma: Results of a Prospectively Randomized Trial of
The German Cooperative Renal Carcinoma Immunotherapy Group (DGCIN)
Proc Am Soc Clin Oncol (ASCO Meeting Abstract)
1999 18 : Abstract 1727
[You can find this abstract on the ASCO website (I can't link directly because ASCO won't provide a stable URL)]
Comment: This is an earlier report on Atzpodien 2002a. I
cite it mainly because it although the triple drug + 13-CRA arm and triple drug
alone arm had similar response rates, there is a suggestions that the 13-CRA
arm has a higher complete response rate, which in turn might lead to improved
long term survival. The other data here suggesting that adding 13-CRA improves
efficacy appears to have been washed out after more patients were accrued and
more follow-up time was added. See< Atzpodien 2002a.
Strangely, in Dr. Atzpodien's long term study [Atzpodien 2002]which shows strikingly increased survival with the Atzpodien regimen + 13-CRA in a non-randomized comparison, they say that prospective randomized studies are needed without specifically mentioning that they have done just such a study. Incredibly, they reference this study in the very same sentence but only to support a general claim that drugs like 13-CRA might synergize with IL-2, and in the very next clause they then go on to say, "this has not been demonstrated prospectively in randomized studies." So what gives here? I really don't know - perhaps the report on this study was thought to be too preliminary to support a claim that any benefit had been yet been "demonstrated" - whatever the reason, I find it rather unsettling. Interleukin-2 in combination with interferon-alpha and
5-fluorouracil for metastatic renal cell cancer.
Comment: This was the first report on the triple drug therapy and it was
small with only 35 patients but it defined
the characteristics of this treatment in the hands of Dr. Atzpodien.
Phase II trial of interleukin 2, interferon alpha, and
5-fluorouracil in metastatic renal cell cancer: a cytokine working group study.
Clin Cancer Res.
2000 Sep;6(9):3442-50.
[PubMed Abstract (will open in new window)]
[Free Full Text (will open in new window)]
Comment: This study of the Atzpodien triple drug therapy in 50 patients
failed to confirm Atzpodien's results. The response rate was only 19%. Although
there were only 2 complete responses, they converted 8 patients, including some
with stable disease, to CR with surgery and these patients did very well.
Of note, they saw considerably worse side effects than Atzpodien did with grade 4 (life threatening) side effects in some patients and grade 3 side effects in more. In their hands, the 5-FU caused more frequent lowering of blood counts than in Atzpodien's. It's very unclear why this study had worse results. The doctors involved are some of the most experienced kidney cancer and IL-2 doctors in the world. They did have a modestly higher percentage of patients with the kidney in place (26%) but this can't account for much of the difference. With respect to the increased side effects, they argue that Atzpodien relied on patient self-assessments and assessments from general practitioners which would be less reliable, but reading the description of Atzpodien's comprehensive patient management program [Hanninen 1996], I am not convinced. Instead, I think their patient management program may have resulted in better management of side effects. See my comments for Hanninen 1996for more. Furthermore, even if it were true that Atzpodien's group underreported grade III and IV side effects relative to this and possibly other studies, apparently it didn't result in major complications. It certainly would have resulted in fewer dose reductions and more treatment delivered which could account for better results. Also Atzpodien [Hanninen 1996] apparently only temporarily reduced the dose for grade 3 side effects while in this study, a grade 3 side effect triggered a permanent dose reduction. Thus Atzpodien pushed through side effects more aggressively. Interleukin 2, interferon alpha and 5-fluorouracil in
the treatment of metastatic renal cell carcinoma, results of Czech Cooperative
Group
Proc Am Soc Clin Oncol (ASCO Meeting Abstract)
2003 22 : Abstract 1659
[You can find this abstract on the ASCO website (I can't link directly because ASCO won't provide a stable URL)]
Comment: This ASCO abstract reported similar results to Dr. Atzpodien's
and provides some independent confirmation.
Interleukin-2 based home therapy of metastatic renal
cell carcinoma: risks and benefits in 215 consecutive single institution
patients.
Comment: This study is in many respects the predecessor of Atzpodien's
2002 long term study [Atzpodien 2002] and is very similar in
design. It reports on three different outpatient IL-2 based treatments, only
here it's IL-2 alone, IL-2 + Interferon and the triple drug treatment. LikeAtzpodien 2002, this reports on consecutive patients treated at
one hospital, and in fact at the same one as Atzpodien 2002. The
time span when patients started treatment is also a subset ofAtzpodien 2002, and so I presume that Atzpodien 2002includes the patients reported here for IL-2 + Interferon and the
triple drug treatments or at least those who where in better shape (see
below).
Because of this, [Atzpodien 2002] is a better source of data on these treatments because there is longer follow-up and because they accrued additional patients. The one piece of data available here that is not inAtzpodien 2002, which didn't report response rate by treatment, is that among the 120 triple drug patients reported here 39% responded, including 11% complete responses. This does provide an interesting demonstration of how time and more patients can make things look different. In this study, patients who got the Triple Drug Treatment had better survival then those who got IL-2 + Interferon. This would have been the prime justification for using the three drug treatment. InAtzpodien 2002 these two treatments had identical survival. What has happened is both that they accrued more patients to both treatments (but mainly to the triple drug treatment), and that patients who had short follow-up in this study had longer follow-up in the 2002 study. With these factors combined, what looked like a difference in this study vanished in the later study. Most patients had only modest grade 1 and 2 side effects, though with the constellation of typical IL-2 side effects it must still have been pretty miserable. A small minority of patients had a grade 3 side effect which triggered a temporary dose reduction. They don't report the exact number of patients who needed a dose reduction. There weren't any grade 4 side effects at all. There is one other little nit here. Atzpodien 2002 required patients have Karnofsky performance status > 80% which corresponds to ECOG performance status 0 or 1, while this study included some sicker patients with ECOG status > 1 - 10 of 79 patients on the two drug treatment, and 23 of 120 on the triple drug treatment. Therefore, assuming Atzpodien 2002was correctly reported, it must've left out the sicker patients that were in this study. This does leave open a small chance that the triple drug treatment is more effective than the two drug treatment in sicker patients and that this could contribute to the difference between these treatments seen in this study that was not seen in Atzpodien 2002. It would certainly be better if papers which include data on previously reported patients clearly referenced the prior studies and specified which patients from those studies were included, rather than leaving it to data detectives to scour the literature and deduce what happened from clues. Finally, Dutcher 2000, which tested the triple drug therapy and found more side effects and less response than reported here, criticizes this study for having general practitioners and patients report toxicity. Actually as the authors describe here, they had a comprehensive program for managing these patients during treatment. This program included two weekly visits with general practitioners and a weekly visit with an oncologist. The general practitioners had been given training in immunotherapy, and everyone, including patients and nurses, had access to a 24 hour help line. So in addition to the self-assessments, and assessments by trained general practitioners, patients were also evaluated by oncologists. I think it's possible that this comprehensive and intensive approach actually resulted in better management of side effects. Immunochemotherapy for metastatic renal cell carcinoma
using a regimen of interleukin-2, interferon-alpha and 5-fluorouracil.
Comment: This study of triple drug therapy in 34 patients had results
which were almost as good as Atzpodien's with a 38% response rate, 9% complete
and 29% partial. Given the small number of patients, one can't say they were
different, and in fact overall this study was quite similar toAtzpodien 1993.
The patients overall were in good shape but not quite as good as Atzpodien's 1993 study. Not quite as many patients had had a nephrectomy - 26/34 versus 34/35, and 7 patients were potentially ECOG status 2 versus none forAtzpodien 1993. Again like, Atzpodien 1993, side effects were moderate (grade II) in most patients with relatively few (15%) experiencing any grade III side effects. Overall, this confirmsAtzpodien 1993 and Atzpodien's favorable results in general. A phase II study of interferon-alpha, interleukin-2 and
5-fluorouracil in advanced renal carcinoma: clinical data and laboratory
evidence of protease
activation.
Comment: This 55 patient study of the Atzpodien regime didn't have
nearly as good results at Atzpodien, but the patients were in much worse shape.
40% of the patients still had their kidney in place (patients with the kidney
in place typically have a much lower response rate), compared to less than 5%
of patients with their kidney still in place in Atzpodien's studies
[Atzpodien 1993, Atzpodien 2002
Fewer than half the patients were asymptomatic (Performance status 0) and 22%
were sicker than usually allowed for immunotherapy trials (performance status
2). Few patients had only one site of disease (meaning affected organ) and in
fact about half had three or more sites, indicating very advanced disease.
There were 9 partial responses (16%) total, but sub-groups of better prognosis patients had a better response rate, in particular there were responses in 8/33 (24%) patients who had had a nephrectomy (and only one brief response among the 22 patients who still had their kidney in place). This included patients who weren't evaluable for response because they didn't complete the first treatment cycle, but I think you have to count patients with severe side effects or early progression as treatment failures. Many patients had severe side effects - 44% had a grade III side effect or worse so this was also more toxic than Atzpodien reported but this isn't surprising since the patients were sicker to begin with. Of note, patients were hospitalized for the three intensive days of IL-2 in the first week of treatment, and also during the intensive IL-2 days in the fourth week if they had severe side effects during the first week. If you have significant symptoms or weakness or other illness and are going to try this treatment consider doing the intensive parts in the hospital. In sum, that this paper had a lower response rate than Atzpodien has reported is no surprise given the poor prognostic factors compared to Atzpodien's patients. I do think this paper is evidence that having the kidney tumor in place is a significant bar to response and that patients should consider nephrectomy prior to this therapy, if possible. Phase III trial of interferon alfa-2a with or without
13-cis-retinoic acid for patients with advanced renal cell carcinoma.
Comment:
I cite this randomized trial of Interferon versus Interferon + 13-CRA to
discuss
evidence of synergy between these two drugs that is relevant to the
plausibility of
adding 13-CRA to the Atzpodien triple drug therapy.
This randomized trial in 284 patients failed to confirmpromising phase II resultsof this combination, when compared to interferon alone based on the primary endpoint of survival. The 12% response rate for the combination arm was much less than the 30% in the Phase II study and much more like a typical Interferon response rate. Despite this the results had many hints suggesting that there is some synergy between Interferon and 13-CRA.
The combination group also had somewhat worse side-effects. Interferon alfa-2a and 13-cis-retinoic acid in renal
cell carcinoma: antitumor activity in a phase II trial and interactions in
vitro.
Comment:
I cite this Phase II trial Interferon + 13-CRA to discuss evidence of synergy
between these two drugs that is relevant to the plausibility of adding 13-CRA
to
the Atzpodien triple drug therapy.
This trial had unusually good results for an interferon trial with 30% responses including some complete responses, which are rarely seen with Interferon alone. Moreover the responses lasted longer than one would expect for Interferon. This study raised hopes that this was a real advance in RCC treatment. Unfortunately, these hopes were mostly dashed by therandomized trial which followed. Effects of 13-cis-Retinoic Acid on Chemoimmunotherapy of
Metastatic Renal Cell Carcinoma-Results of a Retrospective Analysis.
Comment: This non-randomized study compared the results in patients
treated with Atzpodien's triple drug regimen with patients given the triple
drug regimen plus 13-CRA at a single hospital. The numbers were small, only 36
patients in each group. The two groups were comparable in prognostic factors
and there was nothing to suggest the 13-CRA group did any better. In fact,
while
survival between the groups was essentially identical, the 13-CRA group
actually had a lower response rate (25%) than the three drug group (33%) though
this could easily have been just due to chance.
13-CRA caused additional side effects but didn't cause any increase in the number of patients who stopped treatment or required a dose reduction. One patient did die of a heart attack in the 13-CRA group. A minor technical note, the triple drug protocol used here is actually very slightly different from the standard Atzpodien regimen in that the doses of IL-2 and Interferon were the same for all patients rather than scaled for body size. The doses are such that the average patient would get the same as under the Atzpodien regimen with the doses scaled. Results of immunochemotherapy with interleukin-2,
interferon-alpha2 and 5-fluorouracil in the treatment of metastatic renal
cell cancer.
Comment: This study of the Atzpodien triple drug study in 47 patients
had a lower response rate, 19%. Oddly though most of the responses (7 of 9)
were complete responses though these didn't seem to last as well as CR's in RCC
often do with 4 of 7 having relapsed. They observed no response in patients
with bone
metastasis - responses were in lung and lymph node metastasis.
Side effects were moderate - mostly grade 1 and 2 but 36% patients had a grade 3 side effect - mainly fever, chills, or low blood pressure. All of the patients but one had had their kidney out. Most patients were in relatively good shape but the percentage who had no symptoms (Performance Status 0) wasn't reported. Only 5 or the 47 might have had serious symptoms (Performance status 2 or worse). Lack of therapeutic efficacy of tamoxifen in advanced
renal cell carcinoma.
Comment: I cite this study of high dose tamoxifen to comment on the
ethics of Dr. Atzpodien's randomized trial [Atzpodien 2001]which used high dose tamoxifen as the control treatment.
This treatment obtained a single partial response of 3 months duration in one of 62 patients treated with high dose tamoxifen. Some of these patients had significant side-effects and the authors concluded, "Toxicity was substantial, and it was not balanced by therapeutic benefit." What this means is that in their opinion the treatment did more harm than good. It's actually worse than a placebo. It's plain to me that it is unethical to intentionally give patients a treatment which is already known to do more harm than good. It is even more unethical to do so when there are treatments known to be more promising. Immunochemotherapy with interleukin-2, interferon-alpha
and 5-fluorouracil for progressive metastatic renal cell carcinoma: a
multicenter phase II study.
Comment: This study failed to confirm Atzpodien's results. Notably every
patient had had a nephrectomy. They had a rather low 12% response rate with no
complete responses at all. Moreover, about half of the patients had severe side
effects (grade 3 or 4) which required dose reduction. It is possible that the
low response rate is due to inability to deliver the therapy in such a large
percentage of patients without dose reductions. I think their results are
similar to those of Dutcher 2000 and likewise can't be blamed on
poor patient condition or prognostic factors. Again, all of their patients had
had a
nephrectomy, they were virtually all in reasonable condition (Performance
status 0 or 1), and lung and lymph node metastases, which tend to respond well
to IL-2 based therapy, predominated. On the whole, these patients look to be
rather similar to those Atzpodien's group reported on inHanninen 1996 with a 39% response rate.
This CancerGuide Page By Steve Dunn. © Steve Dunn Page Created: October 27, 2003, Last Updated: March 27, 2004 |