Warning Signs of Breast Cancer

elf examination and early detection are the first steps in treating and beating breast cancer. Learn all the possible causes of breast pain, lumps, and tenderness.

Part 1 of 11: Overview

Breast Pain or Lump: Is It Cancer?

A sharp pain in your breast, possibly with some tenderness, can be scary. It may have you wondering if it could be something serious. A breast lump is often the first thing that women and even men notice that spurs a visit to their doctor. Although breast cancer generally shows no symptoms in the early stage, timely detection can turn a story of breast cancer into a survivor's tale.

Part 2 of 11: Causes

Causes of Pain and Tenderness

We often associate pain with something wrong, so when women feel tenderness or pain in their breast, they often assume it to be breast cancer. However, breast pain is rarely the first noticeable symptom of breast cancer. Several other factors can cause the pain.

Clinically known as mastalgia, breast pain can also be caused by the following:

• the fluctuation of hormones caused by menstruation
• some birth control pills
• some infertility treatments
• a bra that doesn't fit
• breast cysts
• large breasts, which may be accompanied by neck, shoulder, or back pain
• stress

Part 3 of 11: Signs and Symptoms

Breast Cancer

A lump in the breast is typically associated with breast cancer, but most of the time, a lump in the breast isn't cancer. From hormonal changes in teens to damaged fat tissue, more than 90 percent of all breast lumps in women in their early 20s to early 50s are noncancerous (benign), according to the Mayo Clinic.

Common causes of benign breast lumps include:

• breast infection
• fibrocystic breast disease (“lumpy breasts”)
• fibroadenoma (noncancerous tumor)
• fat necrosis (damaged tissue)

With fat necrosis, the mass cannot be distinguished from a cancerous lump without a biopsy.

Even though the majority of breast lumps are caused by less severe conditions, new, painless lumps are still the most common symptom of breast cancer.

Early on, a woman may notice a change in her breast when she performs a monthly breast exam or minor abnormal pain that doesn’t seem to go away. Early signs of breast cancer include:

• changes in the shape of the nipple
• breast pain doesn't go away after your next period
• a new lump that doesn’t go away after your next period
• nipple discharge from one breast that is clear, red, brown, or yellow
• unexplained redness, swelling, skin irritation, itchiness, or rash on the breast
• swelling or a lump around the collarbone or under the arm

A lump that is hard with irregular edges is more likely to be cancerous

Later signs of breast cancer include:

• retraction, or inward turning of the nipple
• enlargement of one breast
• dimpling of the breast surface
• an existing lump that gets bigger
• an "orange peel" texture to the skin
• vaginal pain
• unintentional weight loss
• enlarged lymph nodes in the armpit
• visible veins on the breast

Having one or more of these symptoms doesn’t necessarily mean you have breast cancer. Nipple discharge, for example, can also be caused by an infection. See your doctor for a complete evaluation if you experience any of these signs and symptoms.

Part 4 of 11: Warning Signs of Breast Cancer in Men

Men and Breast Cancer

Breast cancer is not typically associated with men. However, male breast cancer can occur in rare instances at any age, although it is more common in older men. Many people do not realize that men have breast tissue too, and those cells can undergo cancerous changes. Since male breast cells are much less developed than women’s breast cells, breast cancer in men is not as common.

The most common symptom of breast cancer in men is a lump in the breast tissue.

Other than a lump, symptoms of breast cancer in men include:

• thickening of the breast tissue
• nipple discharge
• redness or scaling of the nipple
• a nipple that retracts or turns inward
• unexplained redness, swelling, skin irritation, itchiness, or rash on the breast

Since most men do not regularly check their breast tissue for signs of lumps, male breast cancer is often diagnosed much later.

Part 5 of 11: Exams

Breast Exams

When you visit your doctor with concerns about breast pain, tenderness, or a lump, there are common tests they might perform.

Physical examination

Your doctor will examine your breasts, the skin on your breasts, and check for nipple problems and discharge. He or she may also feel your breasts and armpits to look for lumps.

Medical History

Your doctor will also ask you questions about your health history, including any medications you might be taking, as well as the medical history of immediate family members. Since breast cancer can sometimes be related to your genes, it’s important to tell your doctor about any family history of breast cancer. Your doctor will also ask you about your symptoms, including when you first noticed them.

Mammogram

Your doctor may request an X-ray of the breast to help distinguish between a benign and malignant mass.

Ultrasound

Ultrasonic sound waves can be used to produce an image of the tissue.

MRI

Your doctor may suggest an MRI in conjunction with other tests. MRI is another noninvasive imaging test used to examine breast tissue.

Biopsy

A removal of a small amount of breast tissue can be used for testing.

Part 6 of 11: Types

Types of Breast Cancer

There are two categories that reflect the nature of breast cancer:

• Noninvasive (in situ) cancer is cancer that has not spread from the original tissue. This is referred to as stage 0.
• Invasive (infiltrating) cancer is cancer that has spread to surrounding tissues. These are categorized as stages 1, 2, 3, or 4.

The tissue affected determines the type of cancer:

• Ductal carcinoma is a cancer that forms in the lining of the milk ducts. This is the most common type of breast cancer.
• Lobular carcinoma is cancer in the lobules of the breast. The lobules are where milk is produced.
• Sarcoma is cancer in the breast's connective tissue. This is a rare type of breast cancer.

Part 7 of 11: Growth

Genes and Hormones Affect Cancer Growth

Geneticists are starting to learn how genes affect the growth of cancer and have even identified one:

• The HER2 gene in cancer cells fuels their growth. Medications can help shut the HER2 gene down.

Like genes, hormones may also speed up the growth of some types of breast cancers that have hormone receptors.

• If a cancer is estrogen receptor-positive, it responds to estrogen.
• If a cancer is progesterone receptor-positive, it responds to progesterone.
• If a cancer is hormone receptor-negative, it has no hormone receptors

Part 8 of 11: Treatments

Treatments

Depending on the type and stage of cancer, treatments can vary. However, there are some common practices doctors and specialists use to combat breast cancer:

• A lumpectomy is when your doctor removes the tumor while leaving your breast intact.
• A mastectomy is when your doctor surgically removes all of your breast tissue including the tumor and connecting tissue.
• Chemotherapy is the most common cancer treatment, and it involves the use of anticancer drugs. These drugs interfere with cells' ability to reproduce.
• Radiation uses X-rays to treat cancer directly.
• Hormone and targeted therapy can be used when either genes or hormones play a part in the cancer's growth.

Part 9 of 11: Warning Signs of Recurrence

Recurrence

Despite initial treatment and success, breast cancer can sometimes come back. This is called recurrence, which happens when a small amount of cells escape the initial treatment.

Symptoms of a recurrence in the same place as the first breast cancer are very similar to symptoms of the first breast cancer. They include:

• a new breast lump
• changes to the nipple
• redness or swelling of the breast
• a new thickening near the mastectomy scar

If breast cancer comes back regionally, it means that the cancer has returned to the lymph nodes or close by the original cancer but not exactly the same place. The symptoms may be slightly different.

Symptoms of a regional recurrence may include:

• lumps in your lymph nodes or near the collarbone
• chest pain
• pain or loss of sensation in your arm or shoulder
• swelling in your arm on the same side as the original breast cancer

If you’ve had a mastectomy or other surgery related to breast cancer, you might get lumps or bumps caused by scar tissue in the reconstructed breast. This is not cancer, but you should let your doctor know about them so they can be monitored.

Part 10 of 11: Outlook

Outlook

As with any cancer, early detection and treatment are major factors in determining the outcome. Breast cancer is easily treated and usually curable when detected in the earliest of stages.

The American Cancer Society says the five-year survival rate for breast cancer that is stage 0 to stage 2 is more than 90 percent. The five-year survival rate for stage 3 cancer is more than 70 percent.

Part 11 of 11: Prevention

Stay Informed

Breast cancer is the most common cancer in women, according to the World Health Organization. Whether you're concerned about breast pain or tenderness, it's important to stay informed on risk factors and warning signs of breast cancer.

The best way to fight breast cancer is early detection, whether that includes self-examinations, annual breast exams at your doctor’s office, or regular mammograms. If you're worried that your breast pain or tenderness could be something serious, make an appointment with your doctor today. If you find a lump in your breast (even if your most recent mammogram was normal), see your doctor.

F,Sc Physics Part II Chapter 13

ELECTRIC CURRENT
	ELECTRIC CURRENT
	"Electric current is defined as the amount of electric charge                                    passing through a cross section of a conductor in unit time."In other words                                "The rate of flow of electric charge through a cross                                                                           section of a conductor is called Electric Current". Mathematically                                          Electric current = electric charge / time
		Unit of electric current is AMPERE.      1 ampere = 1 coulomb / 1 sec
		AMPERE
	In S.I system unit of electric current is ampere. Ampere is defined as:                      “Current through a conductor will be 1 ampere if one coulomb of electric                             charge passes through any cross section of conductor in 1 second.”                                                                         1 ampere = 1 coulomb / 1 sec
		DIRECTION OF CURRENT
	There are two types of current.
	ELECTRONIC CURRENT
	Electronic current flows from negative to positive terminal.
	CONVENTIONAL CURRENT
	Direction of conventional current is taken from higher potential to the lower potential. RESISTANCE RESISTANCE Opposition offered by the material of conductor in the flow of electric current is called resistance. Resistance opposes the flow of current through a conductor. Resistance of a conductor is due to the collision of free electrons with the atoms of the conductor. It is denoted by “R” FACTORS ON WHICH RESISTANCE DEPENDS (1) Length of conductor Resistance of a conductor is directly proportional to the length of conductor .                                                         R a L…………….(a) (2) Area of cross section of conductor Resistance of a conductor is inversely proportional to area of cross section of conductor.                                                         R a 1 / A……………….(b) Combining (a) and (b)                                                 Where  r = resistivity of material of conductor RESISTIVITY Resistivity is an electrical property of material . It is defined as the resistance of a material or conductor of 1 cubic meter volume.                                         Or It is the resistance of a conductor of unit length and unit area.                                         Or Resistivity of a conductor is the resistance of 1 meter long conductor whose area of cross section is I meter square Unit:     r = ohm x m Different materials have different values of resistivity. A very high value of resistivity indicates high electrical resistance RESISTANCE AND TEMPERATURE Resistance of a conductor is directly proportional to temperature. Reason : With the increase in temperature, vibrational motion of the atoms of conductor increases. Due to increase in vibration, probability of collision between atoms and electrons increases. As a result, resistance of conductor increases. VARIATION IN RESISTANCE OF A MATERIAL AT DIFFERENT TEMPERATURES: (1) Increase in resistance of a conductor is directly proportional to original resistance.                  DR  R1..............(a) (2) Change in resistance is directly proportional to change in temperature.                                                                                 DR  DT………….(b) Combining (a) and (b)                 DR  R1 DT                 DR = (constant) R1DT Here constant = a                 DR = a R1DT Where a = temperature coefficient                                      As  DR = R2 - R1 and  DT = T2  -T1 We get                             R2 – R1 = aR1 (T2 – T1)                R2 = R1 + aR1 (T2 – T1)                          R2 = R1 {1 + aT2 – T1)}When T1 = 0 and T2 = t                Rt = R0 [1 + a((t – 0)]                  Rt = R0 {1 + at} TEMPERATURE COEFFICIENT Fractional change in resistance per unit original resistance per degree change of temperature is called temperature coefficient                DR = aR1DT                   a = DR / R1 DT UNIT 1/ K OR 1/ 0C OHM'S LAW  INTRODUCTION Ohm’s law is a quantitative relation between the potential difference across the ends of a conductor and electric current flowing through it. STATEMENT According to Ohm’s law, "The electric current passing through a conductor is directly proportional to the potential difference between the ends of conductor, if physical conditions of conductor remain constant." I a V MATHEMATICAL REPRESENTATION According to Ohm’s law, I a VI = kV Where K = constant and it is called conductivity of material of conductor. V = I/K or V = I x 1/K [ but 1/K = R (resistance of conductor)] V = I x R GRAPHICAL REPRESENTATION Graph between electric current and potential difference is a straight line. SERIES COMBINATION OF RESISTORS  CHARACTERISTICS  In series combination of resistors there is only one path for the flow of electric current.  Electric current passing through each resistor is same.  Potential difference across each resistor is different and it depends upon the value or resistance.  Equivalent resistance of circuit is always greater than any of the resistance connected in the      circuit. DISADVANTAGE OF SERIES COMBINATION In series combination, if one resistance is damaged then the other resistors will not work. EQUIVALENT RESISTANCE OF CIRCUIT Consider three resistances R1, R4 and R3 connected to one another in series circuit as shown below. Let the circuit is connected to a power supply of voltage 'V' and an electric current 'I' is passing through the circuit. Potential difference across R1 is V1 Potential difference across R2 is V2 Potential difference across R3 is V3 The sum of these Potential differences is equal to 'V'. V = V1 + V2 + V3 According to Ohm's law V = IR Putting the value of V, we get, IRe = IR1 + IR2 + IR3 OR Re = R1 + R2 + R3 PARALLEL COMBINATION OF RESISTORS  CHARACTERISTICS  In parallel combination of resistors there are more than only one paths for the flow of electric      current.  Electric current passing through each resistor is different and it depends upon the value or      resistance.  Potential difference across each resistor is the same.  Equivalent resistance of circuit is always smaller than any of the resistance connected in the      circuit. ADVANTAGE OF PARALLEL COMBINATION In parallel combination, if one resistance is damaged then the other resistors will work properly because there are more than one path for the flow of electric current. EQUIVALENT RESISTANCE OF CIRCUIT Consider three resistance R1, R4 and R3 connected to one another in parallel circuit as shown below. Let the circuit is connected to a power supply of voltage 'V' and an electric current 'I' is passing through the circuit. Electric current passing through R1 is I1 Electric current passing through R2 is I2 Electric current passing through R3 is I3 The sum of all three currents is equal to 'I'. I = I1 + I2 + I3 According to Ohm's law I = V/R Putting the value of I, we get, ELECTROMOTIVE FORCE DEFINITION We know that when electric current is passed through a conductor, energy is dissipated in the form of heat energy. Hence for maintaining a steady current continuous source of energy is required. This source when connected across the resistance maintains a P.D of constant value across its ends and hence supplies energy at the rate at which it is dissipated. The devices such as dry cell, battery or electric generator are the source of emf .This strength of these sources is known as emf. Suppose “q” coulomb of charge requires an amount of work “W” joule to be transported through the source then emf in volts is given by:  EMF = W / q EMF AND TERMINAL POTENTIAL DIFFERENCE Consider a source of emf connected to a resistance “R” through which a steady current “I” flows as shown below: Let the emf of source is E Potential difference across resistance R is V We know that A source of emf also has some resistance which is due to electrolytes and electrodes. Therefore some useful energy of emf-source is used in passing the current through the source. Let the internal resistance of the source is “r” Potential drop across emf source = Vr Since Where V = terminal potential difference When no current is drawn from the source then emf and terminal potential difference are equal. If the current is passing through the circuit then the terminal potential difference is less than that of the emf of the source. Power Dissipation in Resistors When an electric current passes through a conductor, some useful electrical energy is dissipated in the form of heat energy. This loss of electrical energy is due to the collision of charges with the atoms of conductor. Loss of electrical energy in unit time is referred to as "power dissipation in resistor".                     EXPRESSION FOR POWER LOSS Let 'q' amount of electric charge passes through a conductor in unit time, the electric current through the conductor is given by:              I = q/t                            Or              q = I x t ............... (1) During the flow of electric current energy lost in the form of heat is equal to q x V, where V is the potential difference across the ends of conductor. Energy lost = q x V Putting the value of q, we get Energy lost = I x t x V Energy lost/t = VI  But Energy /t = Power Power = VI POWER LOSS IN TERMS OF CURRENT AND RESISTANCE According to Ohm's law V = IR. putting the value of V, we get Power = (IR)I Power = I2R POWER LOSS IN TERMS OF RESISTANCE AND POTENTIAL DIFFERENCE As power = VI and according to Ohm's law I = V/R, putting the value of i, we get Power = VI Power = V (V/R) Power = V2/R     UNIT OF POWER In SI system unit of power is Watt. Other large units are: 1. Kilowatt KW (1000 watt) 2. Megawatt W(106 watt)