Chemo Infusion 4/12—Neuropathy


Before cancer, I can’t recall ever having used the word neuropathy in casual conversation. Even now, any word with the root neuro makes me nervous. Coupled with the suffix pathos its even more pathetic; a word to be avoided. Yet it is unavoidable. Neuropathy is a potential side-effect of chemotherapy because my nerves are among the rapidly growing benign cells that may be inadvertently affected by the poisons of the chemicals I’m taking. It appears, in addition, that should my nerves suffer degradation through serious neuropathy, the effects might not be reversible. Neuropathy, since it affects the extremities (fingers and toes, for example, [although more, as will be seen]) is a decidedly frightening thing to consider. Debilitating effects are more disconcerting to me, even than death, itself. Death, after all, is eventually inevitable. A disability that would make it difficult or impossible to walk, or type on a keyboard, is, I believe, something with which I’d have a very difficult time reconciling. It would take a good deal of psychological and spiritual effort.

Since my diagnosis of cancer, friends and associates have comforted me with promises of prayers for my health. I welcome those. But what I find myself praying for is that I may come to terms and accept whatever it is that is to be. Acceptance dominates my own prayers because it is an attitude somewhat within my control. The effectiveness, method and sophistication of my treatment, (and, particularly, whether or not it may result in a remission of my cancer) is not.


Shakespeare conferred these thoughts on Hamlet, when he penned Hamlet’s famous soliloquy in 1602:

What a piece of work is a man, how noble in reason, how
infinite in faculties, in form and moving how express and
admirable, in action how like an angel, in apprehension how like
a god! the beauty of the world, the paragon of animals…

Shakespeare didn’t know the half of it.

One of the more forbidding (to me) side-effects of chemotherapy is peripheral neuropathy. The term identifies the nerves in one’s extremities, and suggests that the toxicity of the chemotherapies may do damage to the peripheral nerves. The confounding thing is that while there are suggestions about how to minimize or neutralize neuropathy, there’s no assurance that applying such treatments wouldn’t counter the more important aim of reducing my cancerous tumors or obviating their diminution. It doesn’t seem, to anyone, that it is worth the risk of treating neuropathy if the treatment is, at the same time, going to allow the cancer free rein.

Reading about neuropathic studies is—as I have suggested in earlier blogs—not something that I can advise for the non-medically trained (including myself). Nonetheless, the careful and precise language of medical journal articles does convey a sense of the serious investigations of medical science. They reveal the attentiveness of researchers and the careful pondering of observations. Even if I don’t very well comprehend the details of such articles, I can understand their grammar and the logical construction of deductions. The good ones convey to me a sense of confidence in the scientific medical process, even though I wish that the process might be further along: that the hypotheses had already been turned into proven facts. Following are a couple of paragraphs from one article I consulted. It reveals the precision of medical language to which I’m responding. It also identifies the complexity of identifying and defining what may be clinically observed (or not) about neuropathy:

Taken as a group, peripheral neuropathies are the most common remote effect of systemic cancer on the nervous system. Paraneoplastic neuropathies may be classified by their associated neoplasms, or by their clinical presentation. Either classification scheme becomes complicated, in that a given clinical syndrome (eg, sensory neuropathy) occurs in association with a number of different neoplasms. Conversely, a given tumor type can be associated with different neuropathy syndromes. As with other neurologic paraneoplastic disorders, neuropathy is often the presenting feature of the patient’s neoplasm. It is therefore the neurologist’s task to identify a paraneoplastic neuropathy as such. This task is made more difficult by the rarity of paraneoplastic conditions, and by the fact that none of the paraneoplastic neuropathies have a pathognomonic clinical presentation. For at least some paraneoplastic neuropathies there are serologic markers which may be used in diagnosis.

For patients without a known neoplasm who present with a peripheral neuropathy, the likelihood of a paraneoplastic etiology is difficult to quantitate and depends on the particular neuropathy syndrome. For example, severe rapidly progressive sensory neuronopathy is much more likely to be paraneoplastic than a mild, distal, slowly progressive axonal polyneuropathy [3-5]. 

Lacking systematic exposure to medical training, I’m not equipped to do much with this information (save, as I’ve shared with countless students I’ve been privileged to engage, “New, incoming information seems to set up little velcro-like tags in our brains. Once established, additional related information that is received has a place to attach itself. Knowledge seems to grow in one’s brain through such an iterative process as commonalities are reinforced or contradictions are identified.”) With respect to my nervous system, I can take a more generalist approach (for which I have, already, a few velcro hooks in my brain.)

We possess trillions (!) of nerves (more properly, neurons) in our body.  Some can be metres+ in length. We humans could be defined, with at least some legitimacy, as a largish packet of sensory apparatus containing a life-propelling force that maintains the apparatus. Sensory (more properly, afferent) neurons convey messages to the brain and spinal cord from the nerve endings. Motor (or, efferentneurons convey commands away from the central nervous system to the nerves themselves. Autonomic neurons deal with involuntary controls. Here’s how the University of Chicago Center for Peripheral Neuropathy defines the latter. What is evident is that the definition consists of sometimes completely contradictory effects (which seems to me to be a pretty loose definition, indeed; but conveys part of the problems associated with clinical observations and individually different reactions to stimuli:

  • Autonomic nerves control involuntary or semi-voluntary functions, such as heart rate, blood pressure, digestion, and sweating. When the autonomic nerves are damaged, a person’s heart may beat faster or slower. They may get dizzy when standing up, sweat excessively, or have difficulty sweating at all. In addition, autonomic nerve damage may result in difficulty swallowing, nausea, vomiting, diarrhea or constipation, problems with urination, abnormal pupil size, and sexual dysfunction.

While there are three types of neurons, there are various sub-classes that have been identified with a consistent labeling system. (Doesn’t this remind you of sorting screws?):

  • A(alpha), largest and fastest velocity, acts as motor and sensory fibers.
  • A(beta), next largest, acts as motor and sensor
  • A (beta), next largest, acts as motor and sensor
                 A(gama), next largest, acts as motor only.
  • A(delta), next largest, acts as sensory only.
  • B, smaller than A fibers, only acts a motor.
  • C, smallest, acts as motor and sensory.

Furthermore… (I was intending to open this sentence with the word “Finally” but replaced it with “Furthermore”.  It is very clear that we are continually discovering details and specializations that are not at all “final,” nor have yet been systematized or integrated into our knowledge of the “piece of work” of which we are constituted.) So, furthermore, various classes of neuron react to different stimuli (very light touch, more insistent touch, differential pressures, temperature, pain, various types of taste, optical sensory input, light rays of various intensities, sound waves, vibrations, etc.) If I but concentrate and let myself contemplate the distinctions and the capacity of my neurons to convey sensations in such a finely discriminated way, I cannot help but be enthralled. Nor can I be anything but appalled by the thought that any single one of these admirably fine sensational apparati should fail to inform my central nervous system about its subject. Not to feel pain would be dangerous. Not to taste the difference between savory or sweet could be disgusting. Not to feel pressure could inhibit locomotion. And any of the preliminary signs of disorder (ones that cause tingling, phantom pain, oddly burning sensations [all of which are known and possible]) would be uncomfortable and frightening.

Anecdotally, my podiatrist shared with me an odd fact. While the differing classes of nerves each have their specialization, when one specialized class of nerves suffers degradation, all the others—as if in sympathy—suffer disruption as well. She tells me that researchers don’t know why this is so. They don’t understand why the nerves would have evolved with such built-in sympathetic responses.

What I know is that Hamlet was understating his awareness of the admirability of the human body by miles. I also know that when I last went shopping for some low-cal yoghurts in the cooling section of the grocery store, I found that I could barely handle the merely cool yoghurt containers just the short distance to get them from the cooler to my shopping cart. My fingers tingled and burned and hurt so much I had to ask for assistance. It is decidedly difficult not to overreact to such an experience. I know something is going on. My nerves are clearly reacting to the chemotherapy with which I’m infusing myself. I don’t yet think the reactions of my fingers is seriously neuropathic, but my fingers bear evidence that some degradation, at some level, is taking place. I need to pay attention to them as objectively and calmly as I can in order to report the experience accurately to my care-givers. At the same time, what I’m feeling is my body and my nerves. This makes it difficult to be dispassionately objective about it. In truth, I wouldn’t want to be dispassionately objective about these goings on with my body.

Hamlet concludes his reverie on the wonder of man with a judgement against himself for lacking nerve and possessing a destructive attitude:

and yet,
to me, what is this quintessence of dust? Man delights not me—

When I consider the amazingly sophisticated interaction of chemistry, biological cells, and slight electrical signals… and the response of these to the variety of tactile and sensory  stimuli, I feel exactly the opposite of Hamlet. I could praise and admire this body I inhabit with pages of pages of marvelous functional details about which I know, and others I expect to be discovered. Indeed, medical researchers are doing just that in the millions upon millions of pages of observations, clinical trials, treatment results, chemical and molecular analyses. It is enough to make one awestruck.

To be in awe of this Creation is a fine experience to possess and appreciate. I am grateful for it and wish such awareness on everyone I know.