This has been a very interesting thread. While I haven't noticed any change in my sense of smell, my taste buds are really crazy. I have always been a chocolate lover, and that tastes like crap to me now. Some things taste good, and others have really no taste at all. Maybe my sense of smell hasn't changed because I have never been a smoker, but it's disappointing when something really smells good to me, but then, I either can't taste it or it tastes awful.

This topic has long been an issue for my Alex, and has also piqued my "need to know" gene, so I have spent some time poking around the Oncology medical journals and websites for healthcare professionals(I am highly skeptical of other sources). There is an awful lot out there and many theories about the hows and whys of what is going on. I am confident this information is credible BUT there may be inaccuracies as a result of my own misinterpretation of the information (please correct me if you know what I am trying to say but haven't got it right).

Before I share what I have learnt, some definitions:
- hypo - means less of
- a - means lack of
- dys - means disturbance or not normal
- osmia- refers to sense of smell
- geusia - refers to sense of taste

So dysgeusia is disturbance of sense of taste whilst hyposmia means reduction in sense of smell.

The literature struggles to disentangle taste and smell as the pair are interrelated to the point that if one is impaired the other is affected and it is difficult to pinpoint which is impaired to affect the other.

Chemotherapy causes smell and taste disturbances - particularly absent and "wrong" sense of taste and smell. The two culprits relevant to this forum are 5FU and cisplatin. Although I do not recall reading about carboplatin specifically, I would be unsurprised if it too were implicated in some way.

Depending on the trial, 50-80% of patients suffer smell and taste disturbance after chemotherapy. The chemotherapy refers to multiple combinations of chemo agents used as regimen over 9-12 weeks rather than a single agent administered in conjunction with radiation to make the radiation more effective.

There are many suggested mechanisms including
a)direct insult to salivary system - chemo is secreted in the mucous, giving everything a metallic taste.
b)neurotoxicity - chemo damages the nerve system responsible for taste and smell.
c)side effects - chemo causes stomatitis (inflammation and ulceration) and xerostomia (dry mouth due to lack of saliva)which in turn causes dysgeusia and dysosmia.
d)chemo is effective in killing cells that have a high turnover and taste buds have a high turnover rate. One would expect lack of or absent taste bud would result in reduction of ability to taste.
e)chemo causes deficiencies in vitamins and minerals such as zinc which interferes with appetite and taste

We all know that radiation causes dry mouth and ulcers and this would be one of the reasons why radiation is also implicated in the smell and taste disturbances. It also "nukes" taste buds and damages nerves so the outcomes of b) and d) could also be attributed to radiation.

I couldn't find anything about the concept of "heightened smell". Maybe when taste buds and olfactory system regenerate and the nerves recover, it is like the smell of the world after the rain - everything has been washed clean and you get to start again with a fresh set of senses???

Just found this posting and I'm really glad I did. I've been having a really hard time eating and tasting all savoury but sweet has been another story. This has put me in quite a tail spin as I would consider myself somewhat of a "foodie." I'm finally finishing up my last week of radiation with no chemo after a small break. So, my question is after reading a bit of this - do you think I'll have a better chance of recovering my tastebuds and sense of taste in general with not having to go through chemo?

I see patients on here who have had rads only have the same struggles with their eating as others who went with both chemo and rads. With just coming to the end of your treatments, it will be a few weeks before you will be feeling like you are getting better. Its a long process. Have patience and you will get back to your old self or at least pretty close to it. Its a real learning experience adjusting to eating again. One day something will be your favorite food and taste great and the next day it will taste like garbage. Just hang in there and keep trying. Here is list of easy to eat foods, most have a smoother texture to make it easier to eat.
Easy to East Foods

Best wishes!!!

this is such a weird type of cancer, but your taste and sense will return, the rad treatment just messes everything up for a while. first week after rad treatment ends is the worst, but hang in and you'll gradually feel better. long process, but life is worth it, good luck

HI All

I probably need to clarify my last post on this thread.

I did not intend for it to sound like chemotherapy is the main culprit for taste/smell dysfunction, just that it should not be discounted.

Almost everyone who undergoes radiation complains of taste and smell disturbances to some degree and this is a known side effect of radiation and one that is discussed on this forum often. I suspect the magnitude of the effect is dependent on where the radiation is aimed and how large an area is "nuked".

Alex started suffering taste and smell disturbances, thick and ropey saliva, dry mouth and ulcers BEFORE any radiation and during his induction chemotherapy. However, induction chemotherapy is not the same as chemo-radiation which is when a chemotherapy agent is used in conjunction with radiation to assist the effect of radiation.

The side effects and mechanisms I attempted to elucidate in the previous post was as a result of my research into the effect of chemotherapy as a course of treatment (ie 2 or 3 chemotherapy agents used together over a number of weeks/months), and may not apply to chemoradiation which is the application of 1 chemo drug (sometimes 2) to give the radiation a "boost". In this instance it would be difficult to tell if it was the chemo, radiation, or the combination of both that was causing the side effects.

Just thought I'd put what I'm experiencing, after 4 years, on this thread just to see if anyone has anything similar. I also experience a more hightened sense of smell now, but what is more weird is the putrid sweet taste I have starting first thing in the morning, without having eaten anything. I wake with a dry mouth, brush my teeth, then a sort of post nasal drip starts, which has that horrible taste, and continues 24/7. All doctors (ENTs/gastros) have eliminated everything and blame it on long-term after-radiation effects. It started about 2 years ago and is driving me nuts . Anyone? Thanks.
julieann

I was sensitive to smell, especially the hospital smell. I had to wear peppermint oil on my wrist and sniff it as I walked through the doors. For some reason, the smell always hit me as I opened the door. Now when I go in, I take a deep breath just to see how far I have come.

Fascinating thread. To the original poster, I fear your questions may have been somewhat lost in the discussion here. Be patient. Clearly these hyper-sensitivities, whatever the cause, are not uncommon in this challenging context. Don't take it personally. Also, every treatment, and every reaction, is different.

I'm about two years out from my chemo-radiation treatment, went through loss of sweet, then loss of taste-in-general, but never lost my sense of smell. I didn't *notice* an enhancement of smell, but my wife tells me I smell everything before eating it now. I don't feel this is new, but she says so, and perhaps I'm just "testing" for spice levels, since my poor scar-tissue mouth could NOT handle spice for a long time. Most of my taste has returned, I can handle "medium" spice, and my saliva function is about 65% (guessing). I also did go through a period of hyperacusis (greatly increased sensitivity to clanging noises......most annoying), but this, too, has passed. Aside from the dry mouth, my long list of side effects has generally faded away (yay).

Ah, one that stumped my Oncologist was that foods such as pasta sauce would trigger my neck muscles to spasm and cramp.........this was a new one to him!

Wishing everyone going through this, as patient or carer, patience, strength, hope and good support. It can be an incredibly challenging time, and I encourage you to gather as much support as you can. If you don't need it, bonus, but if you do, it's best to have it ready and waiting in the wings.

Last point; for me one of the worst parts was some very bad psychological reactions to the cocktail of drugs used to manage the treatment - whether it was the Fentanyl (an opiate) or the steroids (got the blame from the docs) I'll never know, but for those with sensitivity to drugs, beware! And good luck.