WO1992001419A1 - Method of detecting cancer by measuring lipid-peroxidation using nmr - Google Patents
Method of detecting cancer by measuring lipid-peroxidation using nmr Download PDFInfo
- Publication number
- WO1992001419A1 WO1992001419A1 PCT/US1991/005182 US9105182W WO9201419A1 WO 1992001419 A1 WO1992001419 A1 WO 1992001419A1 US 9105182 W US9105182 W US 9105182W WO 9201419 A1 WO9201419 A1 WO 9201419A1
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- WIPO (PCT)
- Prior art keywords
- spectrum
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- cancer
- abnormal
- resonance
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
- A61K49/00—Preparations for testing in vivo
- A61K49/06—Nuclear magnetic resonance [NMR] contrast preparations; Magnetic resonance imaging [MRI] contrast preparations
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
- G01R33/44—Arrangements or instruments for measuring magnetic variables involving magnetic resonance using nuclear magnetic resonance [NMR]
- G01R33/46—NMR spectroscopy
- G01R33/465—NMR spectroscopy applied to biological material, e.g. in vitro testing
Definitions
- the present invention relates to a diagnostic method and apparatus for the detection of cancer in a living patient.
- NMR nuclear magnetic resonance
- Damadian was the first to propose any medical use for nuclear magnetic resonance (NMR) and that was for the detection of malignancy in tissue. See R. Damadian, "Tumor Detection by Nuclear Magnetic Resonance," Science 171:1151-1153 (1971).
- U.S. Patent 3,789,832 issued to Damadian covers an apparatus and method for application of nuclear magnetic resonance to surgically removed specimens to measure T- ⁇ and ⁇ 2 for proton relaxation times, which values, compared against values for healthy tissue, were taken as an indication of cancer.
- U.S. Patent Nos. 4,411,270 and 4,354,499 issued to Damadian cover apparatus and method for cancer detection with NMR imaging and scanning of whole-body specimens.
- T- ⁇ nuclear magnetic resonance relaxation times
- a resonance line generated by a non-water component of the sample is selected, and the full width of this resonance line, e.g., at half its height, is measured.
- the full width so measured has proved to be a statistically reliable measure of the presence or absence of cancer in the patient.
- the level of triglycerides is determined. If the level of triglycerides is high, then the patient's bodily fluid is further subjected to C-13 nuclear magnetic resonance spectroscopy. The resonance spectrum of the plasma C-13 spectra discriminates between true and false positive results to determine the presence or absence of cancer in the patient with a higher degree of accuracy than was previously possible.
- C-13 NMR looks at the ratio of fatty acids with a single double bond versus fatty acids with two double bonds. However, C-13 is costly and takes a relatively long time to run.
- the present invention is an improved method for screening for the presence of cancer which would eliminate the need to use C-13 to screen for false positives as disclosed in the '021 patent.
- the advantage to the present invention is the the relatively short time to run the test and the relative decrease in cost.
- the principal object of the present invention is to provide a method of confirming a diagnosis by NMR water suppressed proton method of the presence of cancer in a living patient.
- Another object of the present invention is to provide a method to differentiate between true and false positive results obtained in a water suppressed proton NMR test in diagnosing the presence of cancer in a living patient.
- Yet another object of the invention is to provide a method for detecting the presence of cancer in a patient which can be carried out on a sample of the patient's body fluid.
- a further object of the present invention is to provide a method of diagnosing the presence of cancer in a living patient which is more accurate than previously known methods.
- a sample of a patient's bodily fluid is subjected to proton nuclear magnetic resonance spectroscopy to generate a nuclear magnetic resonance spectrum.
- a resonance line generated by a non-water component of the sample is selected, and the area under the peak of the resonance line or the intensity of the peak is measured.
- the area or intensity so measured as compared to a standard control, provides a statistically reliable indication of the presence or absence of cancer in the patient.
- the most abundant polyunsaturated fatty acid in plasma lipoproteins is linoleic acid and the most abundant monounsaturated fatty acid is oleic acid.
- linoleic acid The most abundant polyunsaturated fatty acid in plasma lipoproteins is linoleic acid and the most abundant monounsaturated fatty acid is oleic acid.
- a cancer patients where peroxidation of lipids occurs there will be a decrease of linoleic and other polyunsaturated fatty acids relative to monosaturated fatty acids because they are more reactive with free radicals than monosaturated fatty acids. This results in a decrease in the resonance at 2.8 ppm and an increase in the ratio of the 2.0 ppm/2.8 ppm resonances. Ratios elevated above 2.5 indicate the presence of cancer.
- the resonance at 2.0 and 2.8 ppm are illustrated in the spectrum in Figure 2.
- the bodily fluid is blood, spinal fluid, or bone marrow plasma; although blood plasma or serum is especially advantageous.
- False positive results in the initial proton NMR spectra due to hypertriglyceridemia can be distinguished in the resulting spectra of peroxidized lipoproteins by measuring the ratio of peroxidized lipoproteins and comparing to a standard.
- FIG. 1 is a typical 360 MHz NMR spectrum for the non-water components (water-suppressed) of a plasma sample from a healthy control obtained in accordance with the present invention
- FIG. 2 is an expanded view of the reading of the sample of FIG. 1 showing of the region of the spectra containing resonances at 2.0 and 2.8 ppm ;
- FIG. 3 shows the results of a study performed using the method of the present invention.
- the present invention is a method to detect the presence of cancer in a living patient.
- a sample of a patient's bodily fluid is subjected to proton nuclear magnetic resonance spectroscopy to generate a nuclear magnetic resonance spectrum. Since components of the NMR spectrum which have significant predictive value may be masked by other materials in the sample, the masking is eliminated to produce the NMR spectrum.
- a resonance line generated by a non-water component of the sample is selected, and the full width of this resonance line, e.g., at half its height, is measured to provide a reliable measure of the presence or absence of cancer in the patient.
- the above procedure is described in '050 Fossel patent, the teachings of which are incorporated herein by reference.
- this reading may indicate the presence of cancer in the patient, or it may be a false positive reading. It has been discovered that a major source of false positive readings are persons with high levels of plasma triglycerides.
- the sample tested previously is subjected to a second proton NMR spectroscopy for those who have elevated triglyceride levels.
- the false positive results due to hypertriglyceridemia and, conversely, the presence o.f cancer in the patient can be reliably determined from the resulting ratios of peroxidized lipoproteins as found in the resulting spectra as compared to a standard.
- proton NMR spectroscopy is performed initially on the sample to be tested.
- the water suppressed proton NMR spectrum obtained on human blood plasma is dominated by the resonances of the plasma lipoprotein lipids.
- these non-water resonances are virtually overwhelmed by the water.
- Signal averaging allows observation of resonances of some moieties associated with non-water bodily fluid components, at high magnetic fields, even in the presence of the water resonance.
- the water suppressed proton NMR spectrum of plasma is essentially that of plasma lipoproteins and a few low molecular weight molecules.
- the process of the present invention operates on any lipid-containing bodily fluid, blood, or bone marrow plasma.
- Plasma, whole blood, or serum may be used. While the test may be performed on any such lipid-containing body fluid, work to date has focused on blood plasma.
- the lipids, inclusive of cholesterol, triglycerides and phospholipids are present in the form of lipoproteins.
- the test for cancer will typically be performed in vitro, preferably on serum or plasma.
- the selected fluid of a suspect patient or other person to be screened for cancer is exposed to a magnetic field and radio-frequency energy to generate a nuclear magnetic resonance signal which is then processed to obtain a value for the selected parameter, e.g., W 2 ' f° r ⁇ pid methyl and/or methylene protons.
- a relatively broad range of proton frequencies may be employed, e.g., 60 MHz and higher; 360 MHz or above is a preferred frequency. If cost is not a factor, 500 MHz may be the preferred frequency.
- FIG. 1 shows a water suppressed proton spectrum of a healthy control
- FIG. 2 shows an expanded spectrum of the same sample showing the region from 2.0 to 2.8 ppm (parts per million of resonance frequency) .
- the present invention uses one of a number of conventional water suppression techniques, i.e., techniques for suppression of the water proton NMR signal. Numerous techniques have been devised to suppress the water proton NMR signal in other contexts. These techniques have been set out in the '050 Fossel patent.
- the linewidth at half-height of the resonances of moieties, e.g., methyl and methylene groups, associated with the lipids of plasma lipoproteins are treated as the variable of interest.
- the detected value for the selected parameter is then compared with the corresponding parameter for the healthy controls.
- values for methyl and methylene are averaged and an average value of 33 Hz or less at a proton frequency of 360 MHz (8.45T) or 400 MHz (9.40T) is taken as an indication of malignancy. If a positive reading is obtained from the water suppressed proton NMR spectrum of a plasma sample from a patient, a second level of testing to confirm the diagnosis is performed. First, a conventional test, commonly called a triglyceride analysis, is performed to determine the triglyceride level of the patient.
- the positive reading from the water-suppressed proton NMR spectroscopy is a true positive and indicates the presence of cancer in the patient. If the triglyceride level is above normal, in order to differentiate between true and false positive results, a second proton NMR spectra on the plasma sample already obtained from the patient is conducted.
- False positive results due to hypertriglyceridemia can be reliably distinguished from true positive results by substantial differences in ratio of oxidized lipoproteins in the resulting spectra. Accordingly, the plasma sample already obtained from the suspect patient to be screened is exposed to a magnetic field and radio frequency energy to generate a nuclear magnetic signal which is then processed to obtain a second proton NMR value.
- TE SHEET is indicative.
- the ratio of the height of those two resonances (128/130 ppm) is 0.9 or greater, i.e. the resonance peak at 128 ppm is approximately equal to or taller than that at 130 ppm.
- the heights of the peaks are measured with a ruler or computer from the center of the baseline noise to the top of the peak.
- the ratio of the peak heights is less than 0.9, or the resonance peak at 130 ppm is taller by at least 10% than that at 128 ppm. It should be noted that in patients with hypertriglyceridemia, the ratio of the height of the resonances (128/130 ppm) is the same as normal control values.
- Oleic acid is a monounsaturated fatty acid and is made by the human body. Linoleic acid is a polyunsaturated fatty acid, having two double bonds, and is not made by the human body, but is obtained by consumption. Dietary fatty acids include polyunsaturated acids, such as linoleic acid. A resonance peak in the general region of 128-129 ppm evidences only linoleic acid in the patient. A resonance peak at the general region of 130-131 ppm evidences both oleic and linoleic acid in the patient.
- TITUTE SHEET It has been discovered that the height of those resonance peaks, relative to each other, are affected by certain conditions of the patient. For example, persons with high triglyceride levels usually have a high ratio of linoleic acid to oleic acid levels. Patients with untreated cancer are found to have low levels of linoleic acid in their bodies, presumably because cancer causes a oxidation of polyunsaturated fatty acids, including linoleic acid. This is consistent with the hypothesis that lipids are oxidized by hydroxyl free radicals in cancer patients since polyunsaturated fatty acids are most susceptible to oxidation.
- the resonance peak at 130 ppm will be higher, reflecting the decreased linoleic acid in both peaks. If, however, the peak at 128 ppm is not shorter than that at 130 ppm by more than 7%, no depression, or an insignificant depression, of linoleic acid levels has occurred and the positive result obtained from the proton NMR spectra is confirmed as a false positive and no cancer is present.
- the spectral region between 48 ppm and 80 ppm is far more complex in untreated cancer plasma than in normal control or hypertriglyceridemia plasma.
- more complex is meant that there are more resonance peaks in the region. A resonance peak is counted if its height is 50% greater or more than that of the background noise during a normal testing period. As those skilled in the art will know, the longer data is collected, the noise will lessen and peaks will show more clearly.
- any conventional modern NMR spectrometer may be used in the practice of the present invention.
- an NMR spectrometer with a magnet at constant field strength is used and the NMR signal is Fourier transformed, with the full linewidth at half-height for proton resonances of methyl and methylene groups, and then proton NMR resonances of lipoproteins at 2.0 and 2.8 ppm which are the NMR parameters of interest.
- correct sample preparation and execution is essential to carry out a successful measurement on plasma. Blood is collected in tubes containing 70 1 of a solution of 15% Na 2 EDTA. Blood was maintained at 4°C until centrifugation. Plasma was separated and stored at 4°C until NMR analysis. Plasma samples were never frozen because freezing destroys lipoprotein lipid structural integrity. Samples which showed any visible sign of hemolysis were excluded.
- spectra were obtained at 20-22°C at magnetic field strengths of 360MHz or greater. Other tests were conducted successfully at temperatures of 30°C and 37°C. The samples were shimmed individually on the area of the proton free induction decay until the full width at half height of the water resonance was 4Hz or less. Of course, careful shimming is an assumed component of good NMR laboratory technique. Of course, the field strength used will determine the length of time in which a sample is taken. In addition, to the experimental conditions, accurate results require careful review of a patient's medical record to arrive at the patient classification.
- the spectrometer contains means for selecting at least one and preferably a plurality such as two NMR resonance lines in the NMR spectrum of the sample and, in the first step of the present invention, measuring the linewidth of the line or lines so selected.
- the linewidth is measured at half the height of the line, but this is not necessary and linewidth can be measured at any predetermined fraction of the height of the line in question. Measurement at half of line height is preferred because this is a standard measurement carried out in the field of NMR spectroscopy.
- the spectrometer also contains means for measuring selected peaks, useful for the examination of the second proton NMR spectra.
- the spectrometer also is of conventional construction and includes in addition to all its other structure a means for storing a value or range of values.
- an area or intensity which is either measured directly or derived from a plurality of such direct measurements is compared with a value or range of values which represents the value or range of values to be expected from normal patients, i.e. patients who are free of cancer.
- the spectrometer also includes means for classifying the measured or derived areas of the 2.0 or 2.8 ppm resonances or intensities of the 2.0 or 2.8 ppm and number of peaks as normal (i.e. cancer-free) or abnormal (i.e. cancerous) based upon the stored information. This may be done by comparison, subtraction, or any other appropriate mathematical operation.
- the selecting and measuring means is pre-adjusted to measure the areas or intensities of the 2.0 ppm and 2.8 ppm resonances of the peroxidized lipoproteins in the spectra. This may include suppressing the
- HEET signal of water from the NMR spectrum of the sample may alternatively be done directly where the spectrometer is sensitive enough to do so.
- the method of the present invention was applied to a group of 40 patients.
- the samples were tested in accordance with the method of the instant invention.
- the results as show in Figure 3 show the clustering of those samples indicating malignancy.
- the area of the resonance lines generated according to the method of the instant invention were measured.
- the results show that the ratio of the samples tested (2.0 ppm to 2.8 ppm) is an indicator of the presence of cancer.
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- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Veterinary Medicine (AREA)
- Animal Behavior & Ethology (AREA)
- Epidemiology (AREA)
- Public Health (AREA)
- Radiology & Medical Imaging (AREA)
- Molecular Biology (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Spectroscopy & Molecular Physics (AREA)
- High Energy & Nuclear Physics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Magnetic Resonance Imaging Apparatus (AREA)
- Investigating Or Analysing Biological Materials (AREA)
Abstract
Description
Claims
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FI930177A FI930177A7 (en) | 1990-07-24 | 1993-01-15 | FOERFARANDE FOER UPPTAECKNING AV CANCER GENOM ATT BESTAEMMA LIPIDPEROXIDATION MED NMR-MAETNING |
| NO93930227A NO930227L (en) | 1990-07-24 | 1993-01-22 | PROCEDURE FOR DETERMINING CANCER BY AA MAJOR LIPID PEROXIDATION USING NMR |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US55752990A | 1990-07-24 | 1990-07-24 | |
| US557,529 | 1990-07-24 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO1992001419A1 true WO1992001419A1 (en) | 1992-02-06 |
Family
ID=24225791
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/US1991/005182 Ceased WO1992001419A1 (en) | 1990-07-24 | 1991-07-23 | Method of detecting cancer by measuring lipid-peroxidation using nmr |
Country Status (9)
| Country | Link |
|---|---|
| JP (1) | JPH05509162A (en) |
| AU (1) | AU8413991A (en) |
| CA (1) | CA2087171A1 (en) |
| FI (1) | FI930177A7 (en) |
| IE (1) | IE912581A1 (en) |
| NZ (1) | NZ239080A (en) |
| PT (1) | PT98433B (en) |
| WO (1) | WO1992001419A1 (en) |
| ZA (1) | ZA915771B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6467907B1 (en) | 1999-10-21 | 2002-10-22 | Nidek Co., Ltd. | Apparatus for determining an amount of corneal ablation and surgical apparatus for a cornea |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2006081471A2 (en) | 2005-01-28 | 2006-08-03 | The Regents Of The University Of California | Systems and methods using nuclear magnetic resonance (nmr) spectroscopy to evaluate pain and degenerative properties of tissue |
| US8825131B2 (en) | 2009-10-14 | 2014-09-02 | Nocimed, Llc | MR spectroscopy system and method for diagnosing painful and non-painful intervertebral discs |
| US8761860B2 (en) | 2009-10-14 | 2014-06-24 | Nocimed, Llc | MR spectroscopy system and method for diagnosing painful and non-painful intervertebral discs |
| US9280718B2 (en) | 2010-11-24 | 2016-03-08 | Nocimed, Llc | Systems and methods for automated voxelation of regions of interest for magnetic resonance spectroscopy |
| US8965094B2 (en) | 2012-04-14 | 2015-02-24 | Nocimed, Llc | Magnetic resonance spectroscopy pulse sequence, acquisition, and processing system and method |
| AU2017282665B2 (en) | 2016-06-19 | 2022-05-19 | Aclarion, Inc. | Magnetic resonance spectroscopy system and method for diagnosing pain or infection associated with propionic acid |
-
1991
- 1991-07-23 WO PCT/US1991/005182 patent/WO1992001419A1/en not_active Ceased
- 1991-07-23 AU AU84139/91A patent/AU8413991A/en not_active Abandoned
- 1991-07-23 CA CA002087171A patent/CA2087171A1/en not_active Abandoned
- 1991-07-23 IE IE258191A patent/IE912581A1/en unknown
- 1991-07-23 ZA ZA915771A patent/ZA915771B/en unknown
- 1991-07-23 JP JP3513741A patent/JPH05509162A/en active Pending
- 1991-07-23 NZ NZ239080A patent/NZ239080A/en unknown
- 1991-07-24 PT PT98433A patent/PT98433B/en not_active IP Right Cessation
-
1993
- 1993-01-15 FI FI930177A patent/FI930177A7/en not_active Application Discontinuation
Non-Patent Citations (2)
| Title |
|---|
| NEW ENGLAND JOURNAL OF MEDICINE, Vol 322, No. 14, 5 April 1990, "NMR-Another Cancer Test Disappointment", pp. 1002-3, SHULMAN. * |
| SCIENCE NEWS, Vol. 137, 14 April 1990, "NMR Test Fails to Identify Cancer", p. 236. * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6467907B1 (en) | 1999-10-21 | 2002-10-22 | Nidek Co., Ltd. | Apparatus for determining an amount of corneal ablation and surgical apparatus for a cornea |
Also Published As
| Publication number | Publication date |
|---|---|
| FI930177A0 (en) | 1993-01-15 |
| CA2087171A1 (en) | 1992-01-25 |
| AU8413991A (en) | 1992-02-18 |
| JPH05509162A (en) | 1993-12-16 |
| ZA915771B (en) | 1992-04-29 |
| IE912581A1 (en) | 1992-01-29 |
| PT98433B (en) | 1999-01-29 |
| PT98433A (en) | 1992-07-31 |
| FI930177A7 (en) | 1993-01-15 |
| NZ239080A (en) | 1993-10-26 |
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