WO2015155344A1

WO2015155344A1 - Composition for palpation with increased resolution

Info

Publication number: WO2015155344A1
Application number: PCT/EP2015/057870
Authority: WO
Inventors: Leif Einar Stern
Original assignee: Inoflex AB
Current assignee: Inoflex AB
Priority date: 2014-04-11
Filing date: 2015-04-10
Publication date: 2015-10-15
Anticipated expiration: 2016-10-11

Abstract

A composition for use in palpation for detecting breast cancer, the composition comprising a thickener, a non-ionic, water-soluble poly(ethylene oxide) polymer having molecular weight of at least 100,000 Da, and at least 95 wt% water.

Description

COMPOSITION FOR USE IN PALPATION FOR BREAST CANCER DETECTION

Field of the invention

The present invention relates to a composition for use in palpation for breast cancer detection, by medical practitioners as well as by women themselves, i.e. Breast Self-Examination (BSE).

Background

Breast cancer incidence is steadily increasing in the industrial world. Even though enormous resources have been spent on mammography the breast cancer mortality rate has fallen only marginally. Mammography screening every two years is insufficient for detecting, treating or preventing intractable tumors which develop between the screenings.

Approximately 30% of diagnosed breast cancers are detected between mammography screenings either by BSE or by a palpation examination performed by a medical practitioner according to traditional practice. However, recent experience shows that traditional palpation fails to detect a high degree of lesions.

BSE is recommended to women for detecting early structural changes in the breasts after mammography. Unfortunately, BSE is performed only by a minority of women with the result that malignant tumors may develop and become so large that they are difficult to treat and / or cure. Early detection of tumors provides patients with great benefits.

Modern recommended BSE methods provide a very weak differentiation between normal tissue and growing tumor tissue. Thus, BSE has even criticized as being ineffective for differentiating glands from growing tumor tissue, thereby identification of potential malign tumors to be further examined by doctors are hampered.

Breast tissue in many women contains a number of firm glands that move as the tissue moves during palpation. One reason for the difficulty with BSE is that as the fingertip moves across the skin, friction stretches the skin and underlying soft tissue. The stretched skin and stretched connective tissue are located between the possible different structures and fingertips whilst the fingers need to detect the small differences in vertical force produced when the fingers slide over a solid structure surrounded by soft breast tissue. Typically, the differentiation can be improved somewhat be applying a lubricant, but even with an effective lubricant, such as silicon oil or water and shower gel, the differentiation is not sufficient for effective detection of abnormal tissue. As an example, US 5,873,367 discloses an emulsion or gel to be used as slow drying alternative to a soap solution.

Successful palpation involves clear perception of the very weak pressure difference that occurs transverse to the direction of movement when fingers pass the deviant, firmer structure. Moreover, fingertips have a very dense network of highly sensitive nerve cells linked to a special memory in the brain. Interpretation of Braille is based on these nerves analyzing surface structures as they slide over the Braille. During palpation the fingertips register small abnormal pressure differences but also register the breast skin texture which disrupts the experience of pressure differences. Indeed, the fingertips are often used to analyze surface structures and rarely to register pressure differences.

Effective palpation for breast cancer detection, especially BSE, with high differentiation between normal tissue and growing tumor tissue would be an important step forward in early detection of breast cancer.

Thus, there is a need for improved means for the differentiation between normal tissue and growing tumor tissue in palpation for breast cancer detection.

Summary

Consequently, the present invention seeks to mitigate, alleviate, eliminate or circumvent one or more of the above-identified potential deficiencies in the art and disadvantages singly or in any combination by providing a composition comprising:

- a thickener;

- a non-ionic, water-soluble poly(ethylene oxide) polymer having molecular weight of at least 100,000 Da, such as at least 500,000, at least 1,000,000 Da, or at least

5,000,000 Da; and

- at least 95 wt% water. The composition is used in palpation for breast cancer detection; either by medical practitioners or by women themselves in BSE.

The present composition advantageously provides increased resolution of the breast and clearer perception of the very weak pressure that occurs during palpation when the finger passes a tumor with different hardness than the natural glands in the breast. Thus, it is highly useful in palpation for breast cancer detection.

Further advantageous features of the invention are defined in the dependent claims. In addition, advantageous features of the invention are elaborated in

embodiments disclosed herein. Detailed description of preferred embodiments

The present inventor has previously disclosed that aqueous compositions, comprising at least one thickener and at least one compound forming a shear-thickening fluid when mixed with water, which composition comprises at least 95 wt% water, are useful as sexual lubricants (cf. WO 2011/064383). Such a composition is disclosed to have high water content, be free from preservatives, and to obstruct sperm motility.

While WO 2011/064383 relates to the lubricating properties of such

compositions, no medical or diagnostic usage, such as use in palpation for breast cancer detection, of such compositions has previously been disclosed. Further, there is no disclosure that the lubricous properties of such a composition should be distinct from other lubricants.

It has now however surprisingly been found that compositions comprising a thickener; a non-ionic, water-soluble poly(ethylene oxide) polymer having molecular weight of at least 100,000 Da; and at least 95 wt% water, apart from its lubricating properties also has properties that make the composition well suited for use in palpation. Especially, it was found that such compositions are far more effective than existing lubricants, such as oil, silicone or water based gels, as well as shower gels, when used in palpation methods for detecting breast cancer, whether by medical practitioners or BSE. Thus, earlier and clearer detection of breast cancer is facilitated though the increased resolution of breast tissue provided through use of such a composition.

Thus, an embodiment relates to a composition comprising a thickener; a non- ionic, water-soluble poly(ethylene oxide) polymer having molecular weight of at least 100,000 Da; and at least 95 wt% water for use in palpation for breast cancer detection.

Without being bound to any theory, it is believed that the composition in use, due to the presence of the poly(ethylene oxide) polymer, forms a temporary, elastic, pressure-resistant, ice slippery film when exposed to shear and movement. The formed membrane consists of 99% pure water as "polymerized" hydrogen bonds between the bipolar water and oxygen atoms in a linear polymer which acts as a "catalyst". The shear allows the polymer macromolecules to be oriented in parallel and the elastomer is immediately formed. These properties are believed to provide the superior

differentiation when used in palpation. It is believed that the temporary, non-moving, solid film protects the finger tips, once exposed to shearing strains, such as by movement over the breast. Protecting the finger tips implies that the perception of the very weak pressure difference that occurs transverse to the direction of movement, when fingers pass the deviant, firmer structure, is improved.

This effect may be visualized by a simple example, in which liquid lipstick is applied as a broad string on glass plate. Touching the string with a finger will inevitably result in smearing. However, if firstly covering the same type of string with the present composition, the string could be rubbed without causing smearing thereof. Use of silicon oil to cover the string will in the contrast not prevent smearing thereof. The formation of what is believed to be a shear induced temporary film, protecting the liquid lipstick, will provide a superior resolution in breast palpation.

The thickener should preferably be a pharmaceutically acceptable thickener.

Pharmaceutically acceptable is intended to mean that the compound, at the dosage and concentrations employed, does not cause any unwanted effects. Preferably,

pharmaceutically acceptable compounds are compounds approved for use as pharmaceutical excipients, such as excipients approved for use pharmaceuticals for topical administration to the skin.

Thickeners are typically compounds increasing the viscosity of liquids to which they are added, and thereby thickening such solutions. Without the presence of a thickener the composition will not be viscous enough for controlled use. Further, also the thickener may provide lubricous properties to the composition. However, the extraordinary properties of the present composition when used in palpation are due to the presence of the poly(ethylene oxide) polymer.

Preferably, the thickener may be a compound forming a shear-thinning fluid when mixed with water. By having a thickener forming a shear-thinning fluid when mixed with water, rather than any thickening agent, the lubricious aqueous composition will more easily spread to a thin layer when applied to the breast area.

A composition comprising a thickening agent not forming a shear-thinning fluid when mixed with water may, for some type of applications, be too gel-like, or viscous, to be efficiently spread.

Furthermore, the thickener may preferably be either water-soluble or a compound which swells in the presence of water to form a gel. The dissolution or swelling may require the addition of a base or an acid in order to adjust the pH of the solution or dispersion to be formed. Most preferably, the thickener is a water insoluble hydrophilic compound, which swells in the presence of water to form a gel.

As stated above it is preferred if the thickener is pharmaceutically acceptable. In relation to this, it is preferred that the thickener has such a high molecular weight that it can not penetrate human skin. Potential side effects, local as well as systemic, are minimized if the thickener never enters the body.

One example of a preferred group of thickeners to be used in such a composition, as disclosed herein, is polymers of crosslinked polyacrylate, such as high weight polymers of crosslinked polyacrylate.

Crosslinked polyacrylates are in principle non-degradable by microbes. Thus, they will not promote growth of microbes in the breast area. According to an embodiment, non-degradable by microbes, i.e. non-biodegradable, is intended to mean that the microbes are not able to degrade the compound or polymer. Thus, the compound or polymer does not serve as a nutrient.

By using low amounts of non-biodegradable thickeners, such as polymers of crosslinked polyacrylate, as thickener, the need to add preservatives may be dispensed with.

An example of high weight polymers of crosslinked polyacrylate, are

Carpopol^® polymers. One especially preferred Carbopol^® polymer is Carbopol^® Ultrez 10 (INCI name: Acrylates/C 10-30 alkyl acrylate crosspolymer), which may obtained from Lubrizol Advanced Materials Europe BVBA in Belgium.

Crosslinked polyacrylates are an example of a group of thickeners requiring the addition of a base, such as sodium hydroxide, to swell in water. It seems as if the protonated polymer does not readily swells in water, whereas the de-protonated crosslinked polyacrylate does.

According to one embodiment, high weight polymers of crosslinked polyacrylate are intended to mean polymers, wherein the individual crosslinked polyacrylate polymer chains have an average molecular weight of at least 100,000, such as at least 250,000, as measured by gel permeation chromatography using linear polyacrylic acid as reference, if the individual polyacrylate polymer chains have been polymerized under the same conditions as the crosslinked polymer, and using the same recipe as the crosslinked grades, but without any crosslinking monomer.

The amount of the thickener in the composition, as disclosed herein, may be equal to or less than 2.5 wt%, such as equal to or less than 1.0, 0.5, 0.1, 0.05, or 0.01 wt%. As the thickener, in contrast to water, will not evaporate, a low content of thickener is preferred. However, the content has to be high enough to noticeably affect the viscosity of the composition and give the desired palpation effects. Accordingly, the lubricious aqueous composition may comprise at least 0.005 wt% of the thickener, such as at least 0.01 or 0.1 wt%. The water content of the aqueous composition is at least 95 wt. %. Further, in some embodiments the water content is at least 98 wt%, or even at least 99.0 or at least 99.5 wt%. The high water content provides a significant advantage, as very limited amounts of exogenous substances are administrated to the breast area, compared to water, oil, or silicon based gels of the art, when the composition is being used in a palpation examination.

Non-ionic, high molecular weight, water-soluble poly(ethylene oxide) polymers (PEO-polymers) having a molecular weight of at least 100,000 Da are sold by the Dow Chemical Company under the trademark PolyOx. A preferred type of PolyOx is PolyOx WSR N-60K.

According to an embodiment, the non-ionic, high molecular weight, water- soluble poly(ethylene oxide) polymer has molecular weight of at least 500,000, at least 1,000,000 Da, or even at least 5,000,000.

While poly(ethylene oxide) polymer is a preferred component for providing the composition with protecting properties, it may, according to an embodiment, be replaced with a compound forming a shear-thickening fluid when mixed with water. Such a compound may be a water soluble polymer. Further, such a polymer does typically have a high molecular weight, such as a molecular weight of at least 100,000 Dalton (Da), such as at least 500,000, at least 1,000,000 Da or even at least 5,000,000 Da. In addition, such a polymer is typically a linear, i.e. non-branched, polymer.

Similar to cross-linked polyacrylate, high molecular weight, non-ionic, water- soluble poly(ethylene oxide) polymers are in principle non-degradable by microbes. Thus, they will not promote growth of microbes or disturb the natural bacterial flora. By using low amounts of non-biodegradable compound forming a shear-thickening fluid when mixed with water, such as water-soluble poly(ethylene oxide) polymers, the need to add preservatives may be dispensed with. Further, the composition may not promote bacterial growth to any extent.

The amount of the non-ionic, water-soluble poly(ethylene oxide) polymer, in the composition as disclosed herein may be equal to or less than 2.5 wt%, such as equal to or less than 1.0, 0.5, 0.1, 0.05, or 0.01 wt%. As the non-ionic, water-soluble poly(ethylene oxide) polymer, in contrast to water, will not evaporate, a low content of the non-ionic, water-soluble poly(ethylene oxide) polymer is preferred, so that a minimum of compound is left if/when the water of the composition has evaporated. However, the content has to be high enough to noticeably affect the viscosity of the composition. Accordingly, the composition may comprise at least 0.005 wt% of the non-ionic, water-soluble poly(ethylene oxide) polymer, such as at least 0.01 or 0.1 wt%.

The pH of the composition should preferably be slightly acidic, i.e. below 7.0. An acidic pH will enhance the shelf-life of the product. Furthermore, the rheological properties, especially if a crosslinked polyacrylate is used as thickener, may depend on the pH of the composition. An aqueous solution comprising cross-linked polyacrylates may further be opalescent at a low pH. Accordingly, it is preferred if the pH of the composition is between 3 and 5, such as between 3 and 4 or between 4 and 5, e.g.

between 4.7 and 4.9.

As indicated above the pH may affect the rheological properties of a lubricant comprising crosslinked polyacrylate as thickener. An increase in pH will increase the viscosity of the lubricant.

In order to obtain a pH of 3 to 5, it may be necessary to adjust the pH of the lubricious aqueous composition by adding an acid or a base. Preferably, sodium hydroxide is used to adjust the pH. Sodium is a suitable counter-ion and hydroxide will give water when neutralized.

Another preferred embodiment relates to an aqueous composition, for use in palpation for breast cancer detection, essentially consisting of 98 to 99.9 wt% water, 0.05 to 1 wt% of an essentially none bio-degradable thickener, such as a high weight polymer of crosslinked polyacrylate, eg. Carbopol® Ultrez 10, and 0.05 to 1 wt% of non-ionic, water-soluble poly(ethylene oxide) polymer having a molecular weight of at least 100,000 Da, e.g. PolyOx WSR 301 or PolyOx WSR N-60K. Such a composition may have a pH of 3.8 to 4.5. Further, the water used to obtain the composition may have a total organic carbon content (TOC) of 20 μg/L or less, such as 5 μg/L or less. As such composition comprises only essentially non-biodegradable components, it will not promote growth of micro-organisms.

According to an embodiment, the composition essentially consists of essentially non-biodegradable components and water, thus not promoting growth of microorganisms.

As denoted above, the need to add preservatives may be dispensed with if the lubricious aqueous composition only comprises components being essential nonbiodegradable. As water may contain small amount of organic compounds, which may promote growth of microorganisms, the water used to produce the lubricious aqueous composition may be purified water. Examples of purified water includes distilled water, water purified by reverse osmosis. According to an embodiment, the water used to obtain the lubricious aqueous composition has a total organic carbon (TOC) content of 20 μg/L or less, such as 5 μg/L or less.

The Total Organic Carbon (TOC) is commonly defined as any compound containing a carbon atom except for C0₂, and related substances such as carbonate, bicarbonate and the like. As carbonates are considered to be fully oxidized, they do not form part of the constituents of TOC. Considering this exception to the definition of TOC, an alternative definition of TOC might be total oxidizable carbon.

According to an embodiment, TOC, as used herein, is to be determined in accordance with the method 415.3 disclosed in "DETERMINATION OF TOTAL ORGANIC CARBON AND SPECIFIC UV ABSORBANCE AT 254 nm IN SOURCE WATER AND DRINKING WATER" (EPA Document #: EPA/600/R-05/055) issued by National Exposure Research Laboratory Office of Research and Development U.S. Environmental Protection Agency (EPA) Cincinnati, Ohio.

According to another embodiment, the composition is provided as a kit comprising two mixtures. By blending the two mixtures a composition, as described herein, is obtained. The mixtures are typically blended prior to use, such as less than one week before use. Except for the two mixtures, the kit may comprise a container for the composition once obtained, such as a tube or flask. The first mixture is an aqueous mixture comprising a non-ionic, water-soluble poly(ethylene oxide) polymer having molecular weight of at least 100,000 Da, such as at least 500,000, at least 1,000,000 Da, or at least 5,000,000 Da, and at least 95 wt% water. The second mixture is also an aqueous mixture comprising at least 95 wt% water. Further, the second mixture comprises a thickener of the type described herein. It has been seen that the properties of the present composition are somewhat reduced over time. Thus, it may be

advantageous to provide a kit allowing for preparation of the composition shortly before use, whereby prolonged shelf life may be provided.

The role of each of components obtained by mixing the mixtures has already been described herein. The same guiding principles as applied for providing the composition, also applies for the provision of the two mixtures.

Especially, as already described the thickener may be cross-linked

polyacrylate. Further, the first aqueous mixture and the second aqueous mixture may each comprise at least 98 wt% water, such as at least 99.0 or at least 99.5 wt% water. The second aqueous mixture may comprise between 0.01 and 1 wt% of the thickener. Further, the first aqueous mixture may comprises 0.01 and 1 wt% of the water-soluble poly(ethylene oxide) polymer having molecular weight of at least 100,000 Da. The pH of the each of the two aqueous mixtures may be between 3 and 5, such as between 3 and 4, or between 4 and 5. Further, the second aqueous mixture may essentially consist of 98 to 99.9 wt% water and 0.05 to 1 wt% of the thickener. Similarly the first aqueous mixture may essentially consists of 98 to 99.9 wt% water and 0.05 to 1 wt% of the water-soluble poly(ethylene oxide) polymer having molecular weight of at least 100,000 Da. Also, the first aqueous mixture and the second aqueous mixture may each essentially consists of essentially non-biodegradable components and water. According to another embodiment, the composition described herein is obtained by mixing a first aqueous mixture comprising a non-ionic, water-soluble poly(ethylene oxide) polymer having molecular weight of at least 100,000 Da, such as at least 500,000, at least 1,000,000 Da, or at least 5,000,000 Da, and at least 95 wt% water, and a second aqueous mixture comprising a thickener and at least 95 wt% water prior to use of the composition. The thickener is of the type described herein.

While the present composition has been described as being used in palpation for breast cancer detection, it may also be used in the manufacture of a product for use in palpation for breast cancer detection. Further, a method of palpation for breast cancer detection may include the step of applying the composition to the breast of a woman, either by a medical practitioner or by the woman herself during a BSE. The method further includes the step of palpating the breast in order to differentiate any tumor tissue form normal tissue. The method of palpation is preferably a method of BSE. The method may also include the step of performing a mammography screening prior to the palpation being performed by the medical practitioner or the BSE. Preferably, the method of palpation is used to detect breast cancer.

Without further elaboration, it is believed that one skilled in the art can, using the preceding description, utilize the present invention to its fullest extent. The preferred specific embodiments described herein are, therefore, to be construed as merely illustrative and not limitative of the remainder of the description in any way whatsoever. Further, although the present invention has been described above with reference to specific embodiments, it is not intended to be limited to the specific form set forth herein. Rather, the invention is limited only by the accompanying claims and, other embodiments than the specific above are equally possible within the scope of these appended claims, e.g. different than those described above.

In the claims, the term "comprises/comprising" does not exclude the presence of other elements or steps. Additionally, although individual features may be included in different claims, these may possibly advantageously be combined, and the inclusion in different claims does not imply that a combination of features is not feasible and/or advantageous.

In addition, singular references do not exclude a plurality. The terms "a", "an", "first", "second" etc do not preclude a plurality.

Brief Description of the Figure

Figure 1 shows the relative friction of the composition of the present invention (labeled "Substance") compared to wet ice and existing water- and oil-based lubricants.

Experimental

The following examples are mere examples and should by no mean be interpreted to limit the scope of the invention. Rather, the invention is limited only by the accompanying claims.

An aqueous composition comprising cross-linked polyacrylate and

poly(ethylene oxide) polymer (cf. WO 2011/064383) was provided as described below in the form of a gel.

Water

Water used in preparing the mixtures 1 to 3 was obtained by de-ionizing tap water followed by filtration through active carbon or radiation with UV-light.

Mixture 1

Water (200 kg) was heated to 100°C and stirred to form a vortex. PolyOx WSR 301 powder (1.2 kg; The Dow Chemical Company) was sifted into the heated water and stirred heavily until a clear solution was obtained.

Mixture 2

Water (50 kg) was heated to boiling. Once the temperature had fallen to 40°C, Carbopol Ultrez 21 powder (500g Lubrizol Advanced Materials Europe BVBA) was sifted into the water. The mixture was left until the Carbopol Ultrez 21 powder has swollen. Mixture 3

Water (50 kg) was heated to boiling and aqueous (20%) sodium hydroxide (250 g) was added.

Gel

Mixture 1 , having a temperature of approx. 20°C, was gently stirred and mixture 2 was added thereto, whereafter mixture 3 was added to obtain the gel. The gel was stored under oxygen free atmosphere.

The gel has no adhesion to the environment and is as easy to wipe off. It leaves no stains on fabric and it is completely free from odor and taste. It does not affect living cells or mucous membranes. Not even the eyes react when in contact with the gel.

Example 1

The relative friction of the gel of the present invention, wet ice and several existing water- and oil-based lubricants was measured and compared using a

ForceBoard® developed and sold by Industrial Dynamics Sweden AB. The Forceboard was provided with artificial leather, which was covered by the lubricant (Aqtive Aqua ("substance"), silicon lubricant, shower gel, medical lubricant, and water based lubricant) to be tested. The vertical force used was 50 N and the velocity 10 mm/min. In order to provide a measurement for wet ice (one of the slipperiest known surfaces), a test plate having depression filled with wet ice was used. Further, a value using polished, stiff plastic foil covered with the gel of the present invention was obtained to provide a comparison with wet ice.

The results are provided in Fig. 1. Each bar represents the coefficient of friction obtained as the mean value of repeated (12) measurements.

The results are striking and may provide part of the explanation to the extraordinary, unexpected results from the palpation tests discussed below in example 2. The present composition provided lower friction than any of the other tested lubricants. Actually, it provided nearly as low friction as wet ice, one of the slipperiest known surfaces. Example 2

A highly experienced gynecologist palpated four patients according to traditional practices for detecting benign or malign abnormalities. No changes in the patients' breast tissue were observed.

The gel of the present invention, having extreme gliding capacity, was then applied to the skin of the patients' breast and the palpation was repeated.

In three out of four patients, clear structural changes that could be confirmed by ultrasound were recognized, confirming that that the gel of the present invention provides improved means for differentiating between normal tissue and structurally changed tissue, e.g. growing tumor tissue, in palpation.

Example 3

This example describes the use of the gel of the present invention in a palpation examination of a woman's breast.

Palpation with the gel is best performed when the woman lies on her back. Breast skin and connective tissue strands are then quite lax, which is a prerequisite for effective palpation. The breast is covered with a thin layer of gel on the area to be palpated and the palpation is performed with one or two fingers. When one finger is used, it is clearer to detect small deviations, which gives a more punctuate pressure experience that affects one finger clearer. The formed ice slippery membrane provides a low friction so that breast skin is not moving when the fingers press together the now completely lax tissue. Underlying structures are therefore still and it becomes possible to recognize the different palpations. This increased resolution facilitates the discovery of newly created structures e.g. tumors.

Movement of the fingers occurs practically without friction, which means that the horizontal force is missing and therefore changes in the compressive force experienced are much clearer.

The formed icy membrane also prevents the fingertips in contact with the breast skin so everyone experiences the surface structure absent.

The result is that the woman will be able to recognize their breast structure and to earlier and more clearly detect ongoing changes, which is the purpose of palpation. Recognition of the normal structure creates peace and facilitate the detection of changes e.g. formation of lumps and other growths.

A woman who initiates BSE immediately after a mammogram quickly learns to recognize the healthy structure and quickly notice any small changes when it becomes clear in the limp unresisting breast tissue.

Conclusion

It is obvious that the gel has advantageous affects in palpation. The gel thus has properties, apart from its lubricating properties, making it useful for diagnostic applications.

Claims

1. A composition comprising:

- a thickener;

- a non-ionic, water-soluble poly(ethylene oxide) polymer having molecular weight of at least 100,000 Da, such as at least 500,000, at least 1,000,000 Da, or at least 5,000,000 Da; and

- at least 95 wt% water, wherein said composition is for use in palpation for breast cancer detection.

2. The composition according to claim 1, wherein said palpation is a Breast Self-Examination (BSE).

3. The composition according to claim 1, wherein the palpation is performed by a medical practitioner.

4. The composition according to any one of the preceding claims, wherein said thickener is cross-linked polyacrylate.

5. The composition according to any one of the preceding claims, wherein the composition comprises:

- at least 98 wt% water, such as at least 99.0, or at least 99.5 wt% water;

- between 0.01 and 1 wt% of said thickener; and/or

- between 0.01 and 1 wt% of the water-soluble poly(ethylene oxide) polymer having molecular weight of at least 100,000 Da.

6. The composition according to any one of the preceding claims, wherein the pH of the composition is between 3 and 5, such as between 3 and 4, or between 4 and 5.

7. The composition according to any one of the preceding claims, wherein said composition essentially consists of 98 to 99.9 wt% water, 0.05 to 1 wt% of said thickener, and 0.05 to 1 wt% of the water-soluble poly(ethylene oxide) polymer having molecular weight of at least 100,000 Da.

8. The composition according to any one of the preceding claims, wherein said composition essentially consists of essentially non-biodegradable components and water.

9. The composition according to claim 2, wherein said BSE is performed after a mammography screening.

10. The composition according to claim 3, wherein a mammography screening is performed prior to the palpation being performed by the medical practitioner.

11. A method of palpation for breast cancer detection including the steps of:

- applying a composition comprising:

- a thickener;

- a non-ionic, water-soluble poly(ethylene oxide) polymer having molecular weight of at least 100,000 Da, such as at least 500,000, at least

1,000,000 Da, or at least 5,000,000 Da; and

- at least 95 wt% water,

to the breast of a woman to be palpated; and

- palpating the breast in order to differentiate any tumor tissue from normal tissue.

12. The method according to claim 11, wherein said palpation is a Breast Self- Examination (BSE).

13. The method according to claim 11, wherein the palpation is performed by a medical practitioner.

14. The method according to any one of the claims 11 to 13, wherein said thickener is cross-linked polyacrylate.

15. The method according to any one of the claims 11 to 14, wherein the composition comprises:

- at least 98 wt% water, such as at least 99.0, or at least 99.5 wt% water;

- between 0.01 and 1 wt% of said thickener; and/or - between 0.01 and 1 wt% of the water-soluble poly(ethylene oxide) polymer having molecular weight of at least 100,000 Da.

16. The method according to any one of the claims 11 to 15, wherein the pH of the composition is between 3 and 5, such as between 3 and 4, or between 4 and 5.

17. The method according to any one of the claims 11 to 16, wherein said composition essentially consists of 98 to 99.9 wt% water, 0.05 to 1 wt% of said thickener, and 0.05 to 1 wt% of the water-soluble poly(ethylene oxide) polymer having molecular weight of at least 100,000 Da.

18. The method according to any one of the claims 11 to 17, wherein said composition essentially consists of essentially non-biodegradable components and water.

19. The method according to claim 12, wherein said BSE is performed after a mammography screening.

20. The method according to claim 13, wherein a mammography screening is performed prior to the palpation being performed by the medical practitioner.