Tortoise and Hare

Tortoise and Hare

The profound truth of Aesop’s favorable can be seen in oncology.

We all remember the story:  the tortoise and the hare agreed to a  race.  There is no doubt about who is the faster.  But as a consequence of his early lead, the hare falls asleep and loses the race.

The same phenomenon happens in the treatment of cancer.  There are often breakthroughs, instances of rapid progress in the understanding and treatment of various malignancies.  Industries develop around these advances.  The advances become standard practice.  But the adoption of these new treatments can stand in the way of developing even better treatments.

Checkpoint inhibitor therapy, medicines that block the immune system turn off valve, allowing a more effective immune-driven attack on the cancer, was first developed and approved in melanoma.  There was really no effective treatment for advanced melanoma 10 years ago.  It was an l oncologic tortoise.  Checkpoint inhibitor therapy is not specific to any particular cancer.  There is no clear relationship to melanoma.  But there was so little to offer melanoma that trials could quickly proceed followed by prompt approval of these medicines.

Now checkpoint inhibitors are being studied in a variety of cancers.  They are already approved for squamous cell lung cancer and commonly used for metastatic renal cancer.  These are two other cancers  for which therapeutic options are limited.  But this type of treatment has no clear relationship to the cancer histology.

In cancers that have an array of somewhat more effective treatments, the introduction of checkpoint inhibitor therapy has been much slower.  The tortoise that has become the hare,  cannot enter the race  because of previous rapid advances.

The use of next generation sequencing for the classification of hematologic malignancies is also a case of limited advances blocking the introduction of deeper techniques.  Prior to the introduction of relatively rapid DNA sequencing techniques, hematologic malignancies ( leukemias and lymphomas) were the most extensively molecularly  characterized malignancies, Chromosomal rearrangements defined diseases and directed therapy.  Clonality, a fundamental property of malignancy,  was easily and standardly determined.  Disease could be followed on a molecular level.

However, heterogeneity remained.  Rarely, patients who had a very high probability of excellent response could be identified on the basis of these chromosomal, FISH and limited PCR tests.  But the details remained mysterious and thus the response to treatment remained unpredictable

The introduction of next generation sequencing for the characterization of hematologic malignancies has been slower than from many solid tumors.  The advances made with older molecular techniques have blocked the introduction of the more detailed and extensive analysis now available.  On a molecular level, hematologic malignancies have been asleep

I think there is value in this awareness.  The extreme sub-specialization In oncology has limited the diffusion of advances from one field to another.  The economic arrangement of the healthcare system favors maintaining diagnosis and treatment on a plateau of adequacy It should be helping advanced medicine to increasing excellence.

Sleepers awake