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All of this stuff is promising, and I hope the diagnostic side catches up as well.

Just went to a funeral this weekend for a 40 year old who died of breast cancer 4 weeks after diagnosis at her first annual mammogram.

A lot of skeptical people under 30 here haven't lived through regularly various cancer diagnoses in their friends & family group that your late 30s/early 40s starts to bring.

I don't have the data on it, but anecdotally I notice that women's cancers seem to strike 5-10 years earlier than mens even if they can be caught early & treated well.. Though apparently men have overall worse cancer survival rates.




I'm finishing my PhD in hyperpolarization (hopefully) soon. In my opinion, hyperpolarization will significantly contribute to early-stage diagnosis. We're designing machines, processes, and chemicals that create novel contrast agents for MRI, enabling the localization of cancer cells and even tracking their metabolism. For example, it's possible to inject hyperpolarized pyruvate and track its conversion to lactate. Essentially, this technique boosts the MRI/NMR signal of the contrast agent by up to 100,000-fold. When the contrast agent undergoes metabolism, it creates a unique signal footprint through chemical shift changes, which can aid in characterizing cancer.


I have a question, if you don't mind. What are the nuclei polarized relative to? The molecules in a liquite rotate a lot and I am curious whether the nuclear spins stay aligned with the electron systems or if they remain fixed in an inertial frame.


There are two semi-connected concepts at play here. Polarization in this context refers to the ratio of neutralizing (i.e. "up" vs "down") spins in a given system. For most nuclei in organic systems like protons, carbons, and nitrogens, this ratio is naturally very small, which is the reason that magnetic resonance approaches like MRI usually have poor signal-to-noise. Hyperpolarization techniques usually involve the transfer of polarization from a source of high ratio, like a free electron, to a relevant target (in the original poster's example, 13C in pyruvate). The polarization in this case is hyperpolarized 13C, which has an "up"-to-"down" spin ratio that is much higher than regular 13C, which makes the signal-to-noise that you get from the pyruvate much higher than it would be otherwise. Tumors love pyruvate so this approach means that tumors will light up like a beacon in your MRI.

The physical rotation/tumbling of molecules in an MRI is also very important, because the strong magnetic field is the thing inducing the "up"-vs-"down" split in the first place, and if the molecular motion is happening at a certain frequency with respect to the external magnetic field there are other interactions that can come into play which can affect the coherence of the nuclear spins (i.e. they can fall out of sync). Thankfully, the rotation of a small molecule like pyruvate is very fast (might higher then the "spin" frequency-a.k.a the Larmor frequenct of 13C at the magnetic field strengths involved in MRI) so the physical tumbling of pyruvate doesn't really come into play when trying to measure its signal. It can be another story for molecules that don't tumble quickly, like the ones that make up tissues, fat, etc.


Great explanation. Indeed, the "rotation/tumbling" is nothing to worry about. One of our biggest challenges is relaxation. The moment we polarize, the clock ticks. Usually, the time scope is around 15-90s. I'm in the field of para-hydrogen and built automated systems which carry out the chemical reactions, polarization transfers and sample cleaning. Many hyperpolarization experiments with para-hydrogen prefer nasty solvents as chloroform or methanol. It is a technical challenge to replace them by water within seconds. One of my favorite topics is Xenon hyperpolarization. It's very elegant, no cleaning required, no wet chemistry, and provides amazing lung scans.


Sounds exciting. Routine periodic medical imaging seems like one of those Star Trek technologies thats in reach but not quite been implemented outside of rich countries in Asia.


Hyperpolarization also allows for cheaper MRI scanners. With hyperpolarization, you achieve polarization (needed for SNR) without the need of big magnets (=expensive). Even in rich countries, MRI scanners reach their physical and technical limits. 3T magnets are already 7-figures and costs of bigger magnets will increase non-linearly. Moreover, with higher fields, side effects increase, too.


I believe I read, but can't find the source now, that the sex-specific survival rate is mostly explained by men not catching it and starting treatment as early as women.

Even for cancers that shouldn't be sex-specific, like lung cancer, men are less likely to survive it.


This is very believable given gender differences in being on top of healthcare..


The urgent need for advancements not only in treatment but also in diagnostics


Four weeks... I didn't know that it could be so fast. That's awful.


We were surprised, but it happens. Breast cancer can be very fast moving. Unless they have family history, women aren't told to do annual exams until you hit 40. The symptoms may not be too specific or startling even when it is into stages 3 & 4.

Worth reminding the women in your lives to check their family history and consider getting early exams either way. A lot of times it turns out women do have family history that went undiscussed until they ask mom, aunts, grandmothers, etc.

The other cancers that worry me are the slow moving imperceptible symptomless ones like pancreatic, liver, kidney, etc. Know a few people who around 50 discovered they had stage 2-3 cases due to unrelated scans they got from an accident injury. Some of these you have 5-10+ years window to treat it and live without impact to lifespan.. but most people don't catch it until stage 4 when they actually feel sick and it is too late.


Some people die by cancer, other overcome the cancer, and a small amount don't stand the treatment and die by the chemotherapy. Sometimes by genetics, and can't always be known before. It also depends on how much advanced and aggressive is the tumor.


Pancreatic cancer is the worst. Many people don't get a month.




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