Cancer Patients: Cure the Curable, Treat the Treatable and Avoid Futile Care

During my interview with Jeff Michaels on the March 28, 5:00 P.M. Fox News, we explored the themes of my current book, Outliving Cancer. One of the points that most interested my interviewer was the appropriate use of our laboratory platform for the selection of therapy. He asked, “Are there some patients for whom there is no cure?” I responded by explaining what it is, that our laboratory test is designed to do: “Cure the curable, treat the treatable, and avoid futile care.” Jeff Michaels stopped me and asked that I might repeat what I had just said. It seemed that my succinct description resonated.

However simple this distillation of our work may seem, I realized it was actually rather profound. After all, we are confronting an escalating crisis in medicine. How do we meet the needs of a growing population of cancer patients with shrinking resources? How do we allocate treatments to those most likely to respond and finally, how do we avoid the misadventures of toxic and ineffective therapies for those destined to fail chemotherapeutic intervention? On every level, laboratory models can assist us. For those patients with early stage breast cancer, ovarian cancer, small cell lung cancer, non-Hodgkin lymphoma and many leukemias, the expectation of a cure is well within our reach. These patients must receive the very best treatments from the start.

The larger population of patients we confront are those with diseases like gastric, colon, non-small cell lung, recurrent breast, recurrent ovarian or sarcoma for whom cures are less likely and effective therapies must be tolerable so that they can provide benefit without undue toxicity. These are the patients for whom cancer can become a “chronic disease.”

Finally, we must all confront patients for whom treatments offer little likelihood of benefit, yet significant risks of toxicity. These heavily pretreated patients, or those who present with refractory malignancies like pancreatic, kidney cancer or melanoma – represent a special subset. Here the role of the physician is to decide that almost Shakespearean question, “To treat or not to treat.”

This is a particularly delicate circumstance as it forces the doctor, the patient and the family to confront the most difficult question of all, “Am I dying?” The answer is “maybe.” Without seeming flip, every patient no matter what diagnosis, has some chance of response to therapy. If we examine the performance characteristic of our laboratory analyses, they consistently double response rates. With this group however a doubling of response rate may still provide a rather low likelihood of meaningful benefit. If the laboratory finds drug resistance in this group, it is a near certainty that the patient will not respond.

However distressing this data may be, it may be comforting to know that the patient has left no stone unturned. For those patients where a treatment appears active, despite their diagnosis or treatment history, then the discussion surrounding tolerance, toxicity and realistic likelihood of benefit can be undertaken intelligently. This is the embodiment of rational therapeutics.

The Tumor Micro Environment

As I was reading the October 1 issue of the Journal of Clinical Oncology, past the pages of advertisement by gene profiling companies, I came upon an article of very real interest.

While most scientists continue to focus on cancer-gene analyses, a report in this issue from a collaboration between American and European investigators provided compelling evidence for the role of tumor associated inflammatory cells in metastatic human cancer. (Asgharzadeh, S J Clin Oncol 30 (28)3525–3532 Oct 1, 2012) Through the analysis of children with metastatic neuroblastoma, they found that the degree of infiltration into the tumor environment by macrophages had a profound effect upon clinical outcome. This study confirmed earlier reports that macrophage infiltration is an integral part and potential driver of the malignant process.

Using immunohistochemistry and light microscopy the investigators scored patients for the number of CD163(+) macrophages, representing the alternatively activated (M2) subset within the tumor tissue. They then examined inflammation related gene expressions to develop a “high” risk, “low” risk algorithm and applied it to the progression free survival in these children.

Highly significant differences were observed between the two groups. This report adds to a growing body of literature that describes the interplay between cancer cells and their microenvironment. Similar studies in breast cancer, melanoma and multiple myeloma have shown that tumor cells “co-opt” their non-malignant counterparts as they drive transformation from benign to malignant, from in-situ to invasive and from localized disease to metastatic. These same forces have the potential to strongly influence cellular responses to stressors like chemotherapy and growth factor withdrawal. While we may now be on the verge of identifying these tumor attributes and characterizing their impact upon survival, these analyses represent little more than increasingly sophisticated prognostics.

The task at hand remains the elucidation of those attributes and features that characterize each patient’s tumor response to injury toward ultimate therapeutic response. To address this level of complexity, we need the guidance of more global measures of human tumor biology, measures that incorporate the dynamic interplay between tumors cells, their stroma, vasculature and the inflammatory environment.  These are the “real-time” insights that can only be achieved using human tissue in its native state. Ex vivo analyses offer these insights. Their information moves us from the realm of prognostics to one of predictives, and it is after all predictive measures that our patients are most desperately in need of today.

Beyond Our Borders

I recently returned from Brazil where I participated in a cancer symposium. During my visit I encountered many highly skilled physicians with expertise in breast, thoracic, gastrointestinal and orthopedic oncology. The degree of collegiality and enthusiasm was palpable. The most exciting aspect of my visit was the warm reception and extremely high level of interest in the clinical application of our laboratory platform. It was a refreshing reminder that the parochial thinking of the American oncology community is not the norm throughout the world.

Upon my return, I had the pleasure of meeting a charming 61-year-old woman from New Delhi, India. In review of her chart I recognized her name as a patient for whom we had conducted a study in February of 2012. Her husband, an accomplished businessman, had learned of our laboratory and worked diligently to obtain, process and transport a portion of his wife’s tumor from the surgical suite to our lab. Despite multiply recurrent disease and numerous prior treatments, this patient’s ovarian cancer cells revealed exquisite sensitivity to a drug combination in the laboratory. Her physicians at the Apollo Hospital of New Delhi delivered the treatment exactly as outlined by our lab, and here sitting across from me was the patient in complete remission six months later. The family had traveled from India to meet me and express their thanks.

Each of these experiences speaks volumes for the globalization of cancer care. Cancer patients, whether from Brazil, India or China are more alike than different. Each confronts a seemingly insurmountable adversary. Each in their own way seeks out the best information and advice. And each can be best managed with those treatments found uniquely effective for their tumor. Perhaps once we have conquered cancer in India and Brazil, the EVA-PCD® assay will be ultimately accepted in the United States of America.

Do We Already Have the Tools We Need to Cure Cancer?

The rapid-fire sequence of the annual American Association of Cancer Research (AACR) meeting, held in May, followed by the annual American Society of Cllinical Oncology (ASCO) meeting, held in June, provides the opportunity to put scientific discoveries into perspective as they find their way from theoretical to practical.

Members of AACR, the basic science organization, ponder deep biological questions. Their spin-offs arrive in the hands of members of ASCO as Phase I and Phase II trials, some of which are then reported at ASCO meetings.

Many of the small molecules my laboratory has studied over the years are now slowly making their way from “Gee Whiz” to clinical therapy. At the ASCO meeting I attended many of the Phase I sessions, where alphabet soup compounds had their first “in-human” trials. As most of these compounds are familiar to me, I was very interested in these early, though highly preliminary, results.

Departing from one Developmental Therapy (Phase I) session, with visions of signal transduction pathways in my head, I attended a poster discussion on triple negative breast cancer. For those of you unfamiliar with the term, it refers to an increasingly common form of breast cancer that doesn’t mark for the usual estrogen, progesterone, or HER-2 features. Often occurring in younger patients, this form of breast cancer can be aggressive and unresponsive to some forms of therapy. Much work has gone into defining sub-types of this disease and slow progress is being made.

As I examined the posters, one caught my eye, “Clinical Characteristics and Chemotherapy Options of Triple Negative Breast Cancer: Role of Classic CMF regimen. (Herr, MH et al, abstract #1053, ASCO 2012.) What these investigators showed in a series of 826 breast cancer patients was that those treated with the oldest drug combination for breast cancer (CMF) did better than those who received the more modern and more intensive anthracycline or taxane-based regimens. CMF, originally developed by Italian investigators in the 1970s, was the principal therapy for this disease for two decades before it was replaced, first by anthracycline and later by taxane-based treatments. What struck me was the unexpected superiority of this old regimen over its more modern, toxic and expensive brethren.

I began to wonder about other modern therapies and their real impact upon cancer outcomes. One study in HER-2 positive patients revealed relative equivalency between weekly taxol, every three-week Taxotere and Abraxane-based therapy. Once again, the cheaper, older, less toxic Taxol regimen proved superior. While most of the attendees at the ASCO meeting were considering how the newest VEGF inhibitor Regorafenib, or the addition of aflibercept, might impact their practices, I was somewhat underwhelmed by the results of these statistically significant, but clinically marginal survival advantages, all associated with great expense.

As I pondered the implications of the CMF results in triple negatives and those of the taxol results in HER-2 positives, I considered other old-fashioned therapies with newfound potential. Among them, losartan, the angiotensin antagonist that influences tumor stroma or the results of an earlier published study that identified intraconazole (a widely available anti-fungal therapy), as an inhibitor of the hedgehog pathway. While the pharmaceutical industry promotes the use of vismodegib, a hedgehog inhibitor for basal cell skin cancer, and dozens of trials examine VEGF and FGF inhibitors, I wondered whether losartan or intraconazole or other simple compounds and combinations might not already provide many of the tools we need. Is it possible that effective treatments for cancer are at hand?

Lacking the tools to decipher the signals and combine the agents to greatest effect, are we destined to continue to blindly administer increasingly expensive, toxic, yet arguably no more effective therapies? With the myriad of drugs and combinations available today, might it be that we “can’t see the forest for the trees.”

American Association of Cancer Research 2012

In my last blog, I described my recent attendance at the American Association of Cancer Research (AACR) meeting held in Chicago. This is the premier cancer research convention for basic and translational research. The AACR was the original cancer research organization that pre-dated its sister organization – the American Society of Clinical Oncology. The focus of the AACR meeting is basic research and the presentations are often geared toward PhD level scientific discovery. I find this meeting the most informative for it provides insights into therapy options that may not arrive in the clinical arena for many years.

Among the presentations was a discussion of NextGen genomic analysis allowing an entire human genome to be sequenced within 24 hours. Mapping genetic elements has enabled investigators at the University of Pennsylvania to explore acute leukemia patients at diagnosis and at the time of recurrence. Based upon mutation analysis, different subsets of patients are observed. Mono and Oligo-clonal populations yield new subpopulations following cytoreductive therapy, wherein a small percentage of tumor cells survive and repopulate as the dominant clone.

The NextGen genomic analysis serves as the basis for new solid tumor studies in which breast biopsies are obtained, before and after therapy with aromatase inhibitors, to examine the clonality of the surviving populations.

William R. Sellers, MD, vice president of Novartis Institutes for BioMedical Research Oncology, described a high throughput robotic technology capable of conducting tens of thousands of combinatorial mixtures to determine drug interactions. What I found most interesting was the observation by this investigator that, “Cell culture remains the most effective means of testing drug combinations.” We agree wholeheartedly.

New classes of lymphoma therapies are in development that target B cell signaling pathways. A prototypic agent being Ibrutinib, the Bruton’s tyrosine kinase inhibitor.

Additional developments are examining SYC as a target for small molecule inhibitors.
Our growing understanding of immune regulation is enabling investigators like James Allison to trigger tumor specific immunity. Agents like ipilumimab (AntiCTLA4), combined with other classes of small molecules and/or antibodies directed toward CD28, PD1, and ICOS regulation have the potential to change the landscape in diseases that extend from melanoma to prostate and breast.

The meeting had innumerable sessions and symposia that were geared toward or touched upon the field of metabolomics. As cells jockey for survival they both up- and down-regulate pathways essential to not only energy production but to the biosynthesis of critical metabolic intermediates. The regulation of PKM2 (pyruvate kinase isoenzyme) is now recognized as a pivotal point in the cell’s determination of catabolism (energy production), over anabolism (biosynthesis), with Serine concentrations playing an important regulatory role.

The PI3K pathway is an area of rapidly growing interest as new compounds target this key regulatory protein complex. Both selective and non-selective (pan PI3K) inhibitors are in clinical testing. Paul Workman’s group was honored for their seminal work in this and related areas of drug development. We reported our findings on the dual PI3K/mTOR inhibitor BEZ235 (Nagourney, RA et al Proc AACR, 2586, 2012).

The double-edged sword of immune response was deftly covered by Dr. Coussens who described the profound tumor stimulatory effects of T-cell, B-cell and Macrophage infiltration into the tumor microenvironment. Small molecules now in development that down-regulate macrophage signaling may soon show promise alone or in combination with other classes of drugs.

The RAS/RAF pathway becomes ever more complex as we begin to unravel the feedback loops that respond to small molecule inhibitors like Erlotinib or Vemurafanib. Investigators like Dr. Neal Rosen from Memorial Sloan-Kettering Cancer Center have long argued that simple inhibition at one node in a cascade of signaling pathways will absolutely change the dynamic and redirect up and down stream signals that ultimately overcome inhibition. Strategies to control these “resistance” mechanisms are being developed. Once again we find that simple genomic analyses underestimate the complexity of human systems.

Among the regulatory topics at this year’s meeting was a special symposium on the development and testing of multiple novel (non-FDA approved) compounds in the clinical trial setting. There will need to be a new level of cooperation and communication forged between academia, regulatory entities and the pharmaceutical industry if we are to move this process forward. I am encouraged by the early evidence that all three are recognizing and responding to that reality.

The themes of this year’s meeting included:
1. A renewed focus on the biochemistry of metabolism
2. Clear progress in field of tumor immunology
3. The growing recognition that human tumors exist as microenvironments and not isolated single cells.

We are particularly gratified by the last point.

Our EVA/PCD focus on human tumor aggregates (microspheroids) isolated directly from patients as the most accurate models for chemotherapy selection and drug discovery appears to be gaining support.

A New Target in Breast Cancer Therapy

In many ways the era of targeted therapy began with the recognition that breast cancers expressed estrogen receptors, the original work identified the presence of estrogen receptors by radioimmunoassay. Tumors positive for ER tended to be less aggressive and appear to favor bone sites when they metastasized. Subsequently, drugs capable of blocking the effects of estrogen at the estrogen receptor were developed.  Tamoxifen competes with estrogen at the level of the receptor. This drug became a mainstay with ER positive tumors and continues to be used today, decades after it was first synthesized.

Recognizing that some patients develop resistance to Tamoxifen, additional classes of drugs were developed that reduced the circulating levels of estrogen by inhibiting the enzyme aromatase, this enzyme found in adipose tissue, converts steroid precursors to estrogen.  Despite the benefits of these classes of drugs known as SERMS (selective receptor modulators), many patients break through hormonal therapies and require cytotoxic chemotherapy.

With the identification of HER-2 amplification, a new subclass of breast cancers driven by a mutation in the growth factor family provided yet a new avenue of therapy – trastuzumab (Herceptin). For HER-2 positive breast cancers Herceptin has dramatically changed the landscape. Providing synergy with chemotherapy this monoclonal antibody has also been applied in the adjuvant setting offering survival advantage in those patients with the targeted mutation.

Reports from the San Antonio breast symposium held in Texas last December, provide two new findings.

The first is a clinical trial testing the efficacy of pertuzumab. This novel monoclonal antibody functions by preventing dimerization of HER-2 (The target of Herceptin) with the other members of the human epidermal growth factor family HER-1, HER-3 and HER-4. In so doing, the cross talk between receptors is abrogated and downstream signaling in squelched.

The second important finding regards the use of everolimus. This small molecule derivative of rapamycin blocks cellular signaling through the mTOR pathway. Combining everolimus with the aromatase inhibitor exemestane, improved time to progression.

While these two classes of drugs are different, the most interesting aspect of both reports reflects the downstream pathways that they target. Pertuzumab inhibits signaling at the PI3K pathway, upstream from mTOR. Everolimus blocks mTOR itself, thus both drugs are influencing cell signaling that channel through metabolic pathways PI3K is the membrane signal from insulin, while mTOR is an intermediate in the same pathway. Thus, these are in truest sense of the word, breakthroughs in metabolomics.

Vitamin D and Cancer

A report issued earlier this year (available on Medscape once you register) on Vitamin D levels in breast cancer, identified low levels of this nutritional factor as a risk for breast cancer. Dr. Kristin Skinner reported at the American Association of Breast Surgeons, that the most aggressive forms of breast cancer (i.e. ER negative, triple negative or basal-like) were associated with lower blood levels of vitamin D.

This is one of many reports associating vitamin D levels with disease. Indeed, so many reports on this topic have been published that vitamin D consumption in the U.S. has exploded. While some physicians have made careers promoting the concept, the science of vitamin D is indeed credible and very interesting.

What is vitamin D? Well, although we refer to it as a vitamin, it is, in fact, a hormone. It is obtained from the diet or from exposure to sun. The most potent form of vitamin D is that associated with sunlight exposure. Once in the body, vitamin D interacts with cells at very specific receptors. The term receptor reflects the role of these “landing sites” contained within the cell’s nucleus. As the vitamin D molecule traverses the cell membrane and enters the cell nucleus, it binds with the vitamin D receptor, which connects to the chromosome at a hormone response element and drives the cell machinery forward.

The vitamin D receptor is part of a large collection of genes called the steroid super gene family. These include receptors for estrogen, progesterone, testosterone, and, yes, vitamin D.

What makes the field so interesting is the interaction between these factors. Inside the nucleus are a large variety of receptors. Vitamin D and the other molecules are known as ligands. When the ligands enter the nucleus, they must compete for receptors. This leads to a complicated collection of down-stream events that are unique to the individual. If, for example, your nucleus has a number of orphan receptors (receptors with unclear ligand associations) and these orphan receptors have some binding affinity for the vitamin D, then the down-stream signaling will reflect this new biology.

Many studies have associated vitamin D levels with disease. Prostate cancer, colon cancer, even blood-born tumors may, in part, arise in vitamin D deficient states. But, the most compelling evidence in several analyses supports its protective effect against colon cancer. In one study there was a 15 percent risk reduction for every 10 ug/ml increase in circulating blood levels of calciferol (Gandini S, Int J Cancer. March 11, 2011). What is interesting about the report from the University of Rochester is that it was the most aggressive forms of breast cancer that were found to be associated with Vitamin D deficiency. To date, the correlations with the more common forms of breast cancer have been less positive.

Cardiovascular disease and musculoskeletal diseases are also associated with vitamin D levels. So critical is vitamin D to the well-being of the human that mankind could not easily migrate far north from the equator until he found a source of vitamin D unrelated to the skin synthesis. This source proved to be fish and animals that survived by eating fish. Older readers will remember cod liver oil as a remedy doled out by grandparents. It is ironic that cod liver oil is an excellent source of vitamin D.

While deficiencies of vitamin D are likely to be deleterious, substantially exceeding the normal levels of 30 micrograms/ml have not been shown to further enhance health. It is prudent for patients to monitor their vitamin D levels and highly appropriate for physicians to recommend replacement. Interestingly, a scientific colleague recently commented that sun exposure, by providing active vitamin D, is greatly under appreciated as a healthful activity. He wondered whether the broad use of sunscreens would ultimately save or cost more lives when the aggregate impact of vitamin D levels upon cancer and health is finally understood.

Breast Cancer and Avastin, the Ongoing Saga

As many are now aware, in November of 2011, the United States FDA withdrew approval for bevacizumab (Avastin) for the treatment of breast cancer. Medicare and the National Comprehensive Cancer Network  (NCCN) are now re-examining their guidelines. In the interim, reimbursement for Avastin is a patchwork of approvals and denials across the country.

Into this mix comes an interesting concept apparently floated by Roche’s European affiliates. Described in a brief press release was the suggestion that Roche might be prepared to attach Avastin reimbursement to its efficacy. That is – Roche would only demand payment from patients and third party payers if the treated patient revealed objective evidence of response. This is an interesting idea!

The concept of conditional reimbursement is extremely intriguing. Contrary to contemporary reimbursement policy, the purveyors of therapy would only receive compensation if they could prove benefit, not mind you, benefit in the broad brush Phase III tiny statistically significant result (e.g. the FDA approval of erlotinib plus gemcitabine in pancreatic cancer for a median survival advantage of 10.6 days!), but instead very real benefit on a patient-by-patient basis.

We use erlotinib plus gemcitabine, as well as Avastin combinations, to great benefit for many of our patients and applaud the availability of these drugs and combinations. But we never, just give them. Were the federal government, major payers or HMOs to be prepared to reimburse novel therapies predicated on their efficacy, we might envisage a meaningful advance in cancer therapeutics.

Today, few small laboratories, start-up companies and early stage biotech firms have the resources to marshal multi-million dollar clinical trials to test new therapies. This may in part be why advances in cancer therapy are moving so slowly forward.  The barriers to entry are insurmountable, causing many good ideas to fall by the wayside for lack of the hundreds of millions of dollars required to achieve FDA approval and Medicare reimbursement. But what if on an individual basis, reimbursement policies reflected the most meaningful of all endpoints – individual patient response and survival. Even the largest pharmaceutical companies are now coming to realize that despite their clout they too are suffering under the guidelines forced upon drug developers in this era of ever increasing regulation.

This is a concept worth pursuing. Let’s see where it goes.

Faster than the Speed of Light

Last week, scientists at CERN, the European particle physics laboratory located outside Geneva, Switzerland, conducted an experiment, the results of which now challenge one of the most fundamental principles of modern physics. I speak of Albert Einstein’s 1905 declaration that the speed of light is an absolute and that nothing in the universe could travel faster.

E = MC2, the principle under which nuclear energy and weapons have been developed, as well as all of the corollaries of the theory of relativity were called into question when a series of sub atomic particles, known as neutrinos traveled from Switzerland to Italy at a speed that was 1/60 of a billionth of a second faster than the speed of light. What has followed has been a flurry of interest by departments of physics all over the world. Confronted with this new finding, these investigators will diligently seek to reproduce or refute the findings.

This was not the first time that someone challenged the primacy of Einstein’s 1905 theory. Indeed, during the 1930s, for largely political and anti-Semitic reasons, the Nazi party attempted to disprove Einstein. Yet, all of the political meanderings, personal vendettas and intellectual jealousy could not unseat Einstein’s guiding principle. That is, until objective evidence in the form of the CERN experiments came to the fore.

Science — however lofty — and scientists — however highly regarded — dwell in the same realm as all the rest of us mere mortals. Their biases and preconceived notions often cloud their vision. Comfortable with a given paradigm, they hold unyieldingly to its principles until they are forced, however unwillingly, to relinquish their belief systems in favor of a new understanding. I write of this in the context of laboratory-based therapeutics – a field of scientific investigation that has provided firm evidence of predictive validity. These technologies have improved response, time to progression and survival for patients with leukemia, ovarian, breast and lung cancers, as well as melanoma and other advanced malignancies. Thousands of peer-reviewed published experiences have established the merit of human tumor primary cultures for the prediction of response. Investigations into the newest classes of targeted therapies are providing new insights into their use and combinatorial potential.

Yet,  while the physicists of the world will now rise to the challenge of data, the medical oncologists and their academic counterparts refuse to accept the unimpeachable evidence that supports  the validity of assay-directed therapy. Perhaps if our patients were treated at CERN in Geneva,  their good outcomes would receive the attention they so richly deserve.

Why Some Patients Refuse Chemotherapy – And Why Some of Them Shouldn’t

In the June 13, 2011, issue of Time magazine, Ruth Davis Konigsberg described cancer patients who refuse to take potentially lifesaving therapy. Her article, titled “The Refuseniks – why some cancer patients reject their doctor’s advice,” examined the rationale applied by patients who decline chemotherapy. Many of these patients are rational, articulate, intelligent and capable individuals. While there are those who by virtue of religious belief, underlying depression, or loss of loved ones, decline interventions, many of these patients make compelling arguments in favor of their decisions.

When we examine the basis of these patients’ therapeutic nihilism, much of it reflects the uncertainty of benefit combined with the certainty of toxicity. What these patients articulate is the fundamental dilemma confronted by cancer patients, what we might describe as their logical assessment of “return on investment.”

Everything in life is based on probabilities. Will your husband or wife be true? Will you have a boy or a girl? Will you live to see retirement? Will your nest egg be adequate? Cancer medicine is no different.

Will the treatment I’m being offered extend my life long enough to be worth the short- and medium-term toxicities that I will certainly suffer?

While I cannot address this question with regard to surgery or radiation, I feel uniquely qualified to do so in the context of chemotherapy. What, after all, is a chemosensitivity assay? When correctly performed, it is a laboratory test that dichotomizes groups of patients with average likelihoods of response (e.g. 20%, 30%, 40%, etc.) into those who are more or less likely to respond based on the results. On average, a patient found sensitive in vitro has a twofold improvement in response, while those found resistant have a demonstrably lower likelihood of benefit. We have now shown this to be true in breast, ovarian, and non-small cell lung cancers, as well as melanoma, childhood and adult leukemias, and other diseases.

To address the misgivings of the Refuseniks, we might ask the following question: Would you take a treatment that provided a 30 percent likelihood of benefit? How about a 40 percent? 50 percent? 60 percent? 70 percent? Or 80 percent? While many might decline the pleasure of chemotherapy at a 20-30 percent response rate, a much larger number would look favorably upon a 70 percent response rate. On the flipside, a patient offered a treatment with a 50 percent likelihood of benefit (on average), who by virtue of a lab study realizes that their true response rate is closer to 19 percent (based on resistance in vitro), might very logically (and defensibly) decline treatment. These real life examples reflect the established performance characteristics of our laboratory tests (Nagourney, RA. Ex vivo programmed cell death and the prediction of response to chemotherapy. Current Treatment Options in Oncology 2006, 7:103-110.).

Rather than bemoan the uncertainties of treatment outcome, shouldn’t we, as clinical oncologists, be addressing these patients’ very real misgivings with data and objective information? I, for one, believe so.

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