Paget's disease of the breast is a type of cancer of the breast. Treatment usually involves a lumpectomy or mastectomy to surgically remove the tumour. Chemotherapy and/or radiotherapy may be necessary, but the specific treatment often depends on the characteristics of the underlying breast cancer.

Invasive cancer or extensive ductal carcinoma "in situ" is primarily treated with modified radical mastectomies. The procedure consists in the removal of the breast, the lining over the chest muscles and a part of the lymph nodes from under the arm. In cases of noninvasive cancers, simple mastectomies are performed in which only the breast with the lining over the chest muscles is removed.

Patients suffering from cancer that has not spread beyond the nipple and the surrounding area are often treated with breast-conserving surgery or lumpectomy. They usually undergo radiation therapy after the actual procedure to prevent recurrence. A breast-conserving surgery consists in the removal of the nipple, areola and the part of the breast that is affected by cancer.

In most cases, adjuvant treatment is part of the treatment schema. This type of treatment is normally given to patients with cancer to prevent a potential recurrence of the disease. Whether adjuvant therapy is needed depends upon the type of cancer and whether the cancer cells have spread to the lymph nodes. In Paget's disease, the most common type of adjuvant therapy is radiation following breast-conservative surgery.

Adjuvant therapy may also consist of anticancer drugs or hormone therapies. Hormonal therapy reduces the production of hormones within the body, or prevents the hormones from stimulating the cancer cells to grow, and it is commonly used in cases of invasive cancer by means of drugs such as tamoxifen and anastrozole.

Most women with fibrocystic changes and no symptoms do not need treatment, but closer follow-up may be advised.

There is no widely accepted treatment or prevention strategy for fibrocystic condition. When treatment of symptoms is necessary it follows the same strategies as treatment for cyclical breast pain.

It is controversial whether benign breast conditions improve or worsen with oral contraceptives or hormone replacement therapy.

A few small-scale studies have indicated that the fibrocystic condition may be improved by dietary changes (especially by a reduced intake of caffeine and related methylxanthines or by a reduced intake of salt) and by vitamin supplements.

Small, preliminary studies have shown beneficial effects of iodine supplementation (such as reducing the presence of breast cysts, fibrous tissue plaques and breast pain) in women with fibrocystic breast changes, with elemental iodine (I) being more effective than iodide (I). It is noted that iodine supplementation, via an iodine-based modulation of estrogen influence in the breast, also appears to inhibit early cancer progression in small studies done on breast cancer cells in a lab.. Since treatment success in a lab is often not replicated in humans, more human research is necessary to determine if iodine supplementation prevents breast cancer

A U.S. National Institutes of Health fact sheet of 2011 reported on a randomized, double-blind, placebo-controlled clinical trial performed on 111 women affected by fibrosis and having a history of breast pain. In this trial, daily doses of iodine led to decreased in breast pain, tenderness and nodularity. It was emphasized that further research to clarify iodine's role in fibrocystic breast disease is needed and that large doses of iodine should only be used under the guidance of a physician.

AIP often completely resolves with steroid treatment. The failure to differentiate AIP from malignancy may lead to unnecessary pancreatic resection, and the characteristic lymphoplasmacytic infiltrate of AIP has been found in up to 23% of patients undergoing pancreatic resection for suspected malignancy who are ultimately found to have benign disease. In this subset of patients, a trial of steroid therapy may have prevented a Whipple procedure or complete pancreatectomy for a benign disease which responds well to medical therapy. "This benign disease resembles pancreatic carcinoma both clinically and radiographically. The diagnosis of autoimmune pancreatitis is challenging to make. However, accurate and timely diagnosis may preempt the misdiagnosis of cancer and decrease the number of unnecessary pancreatic resections." Autoimmune pancreatitis responds dramatically to corticosteroid treatment.

If relapse occurs after corticosteroid treatment or corticosteroid treatment is not tolerated, immunomodulators may be used. Immunomodulators such as azathioprine, and 6-mercaptopurine have been shown to extend remission of autoimmune pancreatitis after corticosteroid treatment. If corticosteroid and immunomodulator treatments are not sufficient, rituximab may also be used. Rituximab has been shown to induce and maintain remission.

Initially, an evaluation of malignancy is always indicated. If no abnormality is found, then a surgical duct excision may resolve the symptoms. Treatment also depends on whether single-duct or multiple-duct discharge is present, and whether the symptoms of nipple discharge are distressing to the patient. In some cases, there may be no need for any further intervention; in others, microdochectomy or a total duct excision may be appropriate. If the patient wishes to conserve the ability to breastfeed and only single-duct discharge is present, then ductoscopy or galactography should be considered in view of performing a localised duct excision. Once the cause of the nipple discharge is found, it will be treated by the health provider who will evaluate:

- Whether changing any medicine that has caused the discharge is appropriate

- Whether any lumps should be removed

- Whether some or all of the breast ducts should be removed

- If a prescription for cream to treat skin changes around the nipple will be helpful

- If medicines to treat a health condition are required

If all the tests are normal, treatment may not be necessary. A follow up mamogram mammogram and physical exam may be prescribed within 1 year.

Corticosteroids remain the main treatment modality for IOI. There is usually a dramatic response to this treatment and is often viewed as pathognomonic for this disease. Although response is usually quick, many agree that corticosteroids should be continued on a tapering basis to avoid breakthrough inflammation.

Although many respond to corticosteroid treatment alone, there are several cases in which adjuvant therapy is needed. While many alternatives are available, there is no particular well-established protocol to guide adjuvant therapy. Among the available options there is: surgery, alternative corticosteroid delivery, radiation therapy, non-steroidal anti-inflammatory drugs, cytotoxic agents (chlorambucil, cyclophosphamide), corticosteroid sparing immunosuppressants (methotrexate, cyclosporine, azathioprine), IV immune-globin, plasmapheresis, and biologic treatments (such as TNF-α inhibitors).

Most polyps are benign and do not need to be removed. Polyps larger than 1 cm with co-occurring gallstones occurring in people over the age of 50 may have the gallbladder removed (cholecystectomy), especially if the polyps are several or appear malignant. Laparoscopic surgery is an option for small or solitary polyps.

Breast cysts do not require treatment unless a cyst is large and painful or otherwise uncomfortable. In that case, draining the fluid from a breast cyst can ease symptoms.

Typical treatment involves a Needle aspiration biopsy. Aspirated cysts often recur (come back); definitive treatment may require surgery.

Draining the fluid and then waiting for the cyst to resolve is the main treatment applied in these cases. Moreover, if cysts are aspirated and the fluid looks normal, they do not require any other medical attention apart from following-up to make sure they have completely disappeared. Hormone therapy, by the means of oral contraceptives, is sometimes prescribed to reduce their recurrence and to regulate the menstrual cycle of the patient (which is likely to cause them in the first place). Danazol may also be prescribed to treat this condition and it is usually considered in patients on whom the non-medical treatment fails and the symptoms are intense.

Surgical removal of a breast cyst is necessary only in a few unusual circumstances. If an uncomfortable breast cyst recurs month after month, or if a breast cyst contains blood-tinged fluid and displays other worrisome signs, surgery may be considered.

Most fibroadenomas are simply monitored. Some are treated by surgical excision. They are removed with a small margin of normal breast tissue if the preoperative clinical investigations are suggestive of the necessity of this procedure. A small amount of normal tissue must be removed in case the lesion turns out to be a phyllodes tumour on microscopic examination.

Because needle biopsy is often a reliable diagnostic investigation, some doctors may decide not to operate to remove the lesion, and instead opt for clinical follow-up to observe the lesion over time using clinical examination and mammography to determine the rate of growth, if any, of the lesion. A growth rate of less than sixteen percent per month in women under fifty years of age, and a growth rate of less than thirteen percent per month in women over fifty years of age have been published as safe growth rates for continued non-operative treatment and clinical observation.

Some fibroadenomas respond to treatment with ormeloxifene.

Fibroadenomas have not been shown to recur following complete excision or transform into phyllodes tumours following partial or incomplete excision.

Nipple adenomas are non-cancerous growths, which can recur if not completely surgically removed. There are reported cases of cancers arising within nipple adenomas, and following excision of nipple adenomas, but these are rare occurrences.

In terms of possible treatment for the condition of idiopathic sclerosing mesenteritis, medications such as corticosteroids, tamoxifen and thalidomide have been used.

There are usually no adverse side effects to this condition. In almost all cases it subsides after menopause. A possible complication arises through the fact that cancerous tumors may be more difficult to detect in women with fibrocystic changes.

In lactation mastitis, antibiotics are not needed in the overwhelming majority of cases and should be used only for bacterial infections. Dicloxacillin or cephalexin are sometimes recommended. The effects of antibiotics has not been well studied as of 2013.

There are different opinions on the best treatment of DCIS. Surgical removal, with or without additional radiation therapy or tamoxifen, is the recommended treatment for DCIS by the National Cancer Institute. Surgery may be either a breast-conserving lumpectomy or a mastectomy (complete or partial removal of the affected breast). If a lumpectomy is used it is often combined with radiation therapy. Tamoxifen may be used as hormonal therapy if the cells show estrogen receptor positivity. Chemotherapy is not needed for DCIS since the disease is noninvasive.

While surgery reduces the risk of subsequent cancer, many people never develop cancer even without treatment and there associated side effects. There is no evidence comparing surgery with watchful waiting and some feel watchful waiting may be a reasonable option in certain cases.

Another method of protracting inverted nipples is to have the nipple pierced. This method will only be effective if the nipple can be temporarily protracted. If pierced when protracted, the jewellery may prevent the nipple from returning to its inverted state. The success of both of these methods, from a cosmetic standpoint, is mixed. The piercing may actually correct the overly taut connective tissue to allow the nipple to become detached from underlying connective tissue and resume a more typical appearance.

Danazol, an estrogen biosynthesis inhibitor, tamoxifen, an antagonistic modulator of the estrogen receptor, and bromocriptine, a prolactin-lowering D receptor agonist, are the main drugs used in the treatment of mastodynia and are effective.

Other medications and supplements have been found to be of benefit. Spironolactone (Aldactone), low dose oral contraceptives, low-dose estrogen have helped to relieve pain. Topical anti-inflammatory medications can be used for localized pain. For anti hormonal treatment, danazol (Danocrine) can be helpful. Tamoxifen citrate is used in some cases of severe breast pain. Vitamin E is not effective in relieving pain nor is Evening primrose oil. Vitamin B and Vitamin A have not been consistently found to be beneficial. Flaxseed has shown some activity in the treatment of cyclic mastalgia.

Pain may be relieved by the use of nonsteroidal anti-inflammatory drugs or, for more severe localized pain, by local anaesthetic. Pain may be relieved psychologically by reassurance that it does not signal a serious underlying problem, and an active life style can also effect an improvement.

Information regarding how the pain is real but not necessarily caused by disease can help to understand the problem. Learning breast self-examination helps to orient the woman to normal and expected texture and structure of the breast and nipple. Yearly breast exams may be suggested. Counseling can also be to describe changes that vary during the monthly cycle. Women on hormone replacement therapy may benefit from a dose adjustment. Another non-pharmacological measure to help relieve symptoms of pain may be to use good bra support. Breasts change during adolescence and menopause and refitting may be beneficial. Applying heat and/or ice can bring relief. Dietary changes may also help with the pain. Methylxanthines can be eliminated from the diet to see if a sensitivity is present. Some clinicians recommending a reduction in salt, though no evidence supports this practice.

Other strategies for protracting inverted nipples include regularly stimulating the nipples to a protruding state, in an attempt to gradually loosen the nipple tissue. Some sex toys designed for nipple stimulation, such as suction cups or clamps may also cause inverted nipples to protract or stay protracted longer. There are special devices specifically designed to draw out inverted nipples, or a home-made nipple protractor can be constructed out of a 10 ml disposable syringe. These methods are often used in preparation for breast-feeding, which can sometimes cause inverted nipples to become protracted permanently.

Two methods which are now discouraged are breast shells and the Hoffman technique. Breast shells may be used to apply gentle constant pressure to the areola to try to break any adhesions under the skin that are preventing the nipple from being drawn out. The shells are worn inside the bra. The Hoffman technique is a nipple stretching exercise that may help loosen the adhesions at the base of the nipple when performed several times a day. Although both techniques are heavily promoted, a 1992 study found that not only do shells and the Hoffman technique not promote more successful breastfeeding, but they may also actually disrupt it.

Use of radiation therapy after lumpectomy provides equivalent survival rates to mastectomy, although there is a slightly higher risk of recurrent disease in the same breast in the form of further DCIS or invasive breast cancer. Systematic reviews (including a Cochrane review) indicate that the addition of radiation therapy to lumpectomy reduces recurrence of DCIS or later onset of invasive breast cancer in comparison with breast-conserving surgery alone, without affecting mortality. The Cochrane review did not find any evidence that the radiation therapy had any long-term toxic effects. While the authors caution that longer follow-up will be required before a definitive conclusion can be reached regarding long-term toxicity, they point out that ongoing technical improvements should further restrict radiation exposure in healthy tissues. They do recommend that comprehensive information on potential side effects is given to women who receive this treatment. The addition of radiation therapy to lumpectomy appears to reduce the risk of local recurrence to approximately 12%, of which approximately half will be DCIS and half will be invasive breast cancer; the risk of recurrence is 1% for women undergoing mastectomy.

The procedure to remedy micromastia is breast enlargement, most commonly augmentation mammoplasty using breast implants. Other techniques available involve using muscle flap-based reconstructive surgery techniques (latissimus dorsi and rectus abdominus muscles), microsurgical reconstruction, or fat grafting.

Another potential treatment is hormonal breast enhancement, such as with estrogens.

No pharmacologic treatment has been approved by the U.S. Food and Drug Administration for PSC. Some experts recommend a trial of ursodeoxycholic acid (UDCA), a bile acid occurring naturally in small quantities in humans, as it has been shown to lower elevated liver enzyme numbers in patients with PSC and has proven effective in other cholestatic liver diseases. However, UDCA has yet to be shown to clearly lead to improved liver histology and survival. Guidelines from the American Association for the Study of Liver Diseases and the American College of Gastroenterology do not support the use of UDCA but guidelines from the European Association for the Study of the Liver do endorse the use of moderate doses (13-15 milligrams per kilogram) of UDCA for PSC.

Supportive treatment for PSC symptoms is the cornerstone of management. These therapies are aimed at relieving symptoms such as itching with antipruritics (e.g. bile acid sequestrants such as (cholestyramine)); antibiotics to treat episodes of acute cholangitis; and vitamin supplements, as people with PSC are often deficient in fat-soluble vitamins (vitamin A, vitamin D, vitamin E, and vitamin K).

ERCP and specialized techniques may also be needed to help distinguish between a benign PSC stricture and a bile duct cancer (cholangiocarcinoma).

Liver transplantation is the only proven long-term treatment of PSC, although only a fraction of individuals with PSC will need it. Indications for transplantation include recurrent bacterial cholangitis, decompensated cirrhosis, hepatocellular carcinoma, hilar cholangiocarcinoma, and complications of portal hypertension. Not all patients are candidates for liver transplantation, and some will experience disease recurrence afterward.

Surgical excision of the lesion is done, and depending upon the clinical circumstances, this may or may not involve removal of the involved tooth. With incomplete removal, recurrence is common; some surgeons advocate curettage after extraction of teeth to decrease the overall rate of recurrence.

The development of breast cysts may be prevented to some degree, according to the majority of the specialists. The recommended measures one is able to take in order to avoid the formation of the cysts include practicing good health and avoiding certain medications, eating a balanced diet, taking necessary vitamins and supplements, getting exercise, and avoiding stress.

Although caffeine consumption does not have a scientifically proved connection with the process of cyst development, many women claim that their symptoms are relieved if avoiding it. Some doctors recommend reducing the amount of caffeine in one's diet in terms of both beverages and foods (such as chocolate). Also reducing salt intake may help in alleviating the symptoms of breast cysts, although, again, there is no scientific linkage between these two. Excessive sugar consumption as well as undetected food allergies, such as to gluten or lactose, may also contribute to cyst development.

Chemotherapeutic options include:

- Cyclophosphamide plus methotrexate plus fluorouracil (CMF).

- Cyclophosphamide plus doxorubicin plus fluorouracil (CAF).

- Trastuzumab (monoclonal antibody therapy).

Hormonal options include:

- Orchiectomy.

- Gonadotropin hormone releasing hormone agonist (GNRH agonist) with or without total androgen blockage (anti-androgen).

- Tamoxifen for estrogen receptor–positive patients.

- Progesterone.

- Aromatase inhibitors.

In lactation mastitis, frequent emptying of both breasts by breastfeeding is essential. Also essential is adequate fluid supply for the mother and baby. Use of pumps to empty the breast is now considered somewhat controversial.

For breastfeeding women with light mastitis, massage and application of heat prior to feeding can help as this may aid unblocking the ducts. However, in more severe cases of mastitis heat or massage could make the symptoms worse and cold compresses are better suited to contain the inflammation.

Nonpuerperal mastitis is treated by medication and possibly aspiration or drainage (see in particular treatment of subareolar abscess and treatment of granulomatous mastitis). According to a BMJ best practice report, antibiotics are generally to be used in all nonpuerperal mastitis cases, with replacement of the antibiotics by an antifungal agent such as fluconazole in cases of deep fungal infections, and corticosteroids are to be used in case of granulomatous mastitis (with differential diagnosis to tuberculosis infection of the breast).

The presence of three factors for the prognosis has been suggested, whether there is a palpable mass of the disease, whether lymph nodes are positive and whether there is an underlying malignant cancer.

If there is none of these, the five- and 10-year survival is 85% and 80% respectively, with adjuvant chemotherapy even 95% and 90%. If there is a palpable mass, it is 32% and 31% respectively, with adjuvant chemotherapy (40% and 35%).

Positive lymph-nodes have been positively associated with a palpable mass and affect the prognosis to be now just 28% survival after 10 years (vs 79% without palpable mass and without affected lymph-nodes). Involvement of the lymph nodes does not directly cause any harm, but is merely an indicator of systemic spread.

Furthermore, patients with an identifiable associated underlying breast tumor have a survival rate of 38-40% at five years and a survival rate of 22-33% at 10 years. The death rate of metastatic breast carcinoma in patients with mammary Paget's disease and underlying cancer is 61.3%, with a 10-year cumulative survival rate of 33%.

Surgery has traditionally played a limited role in the treatment of IBC because it is considered essentially a systemic cancer. However, the role of surgical intervention is being reevaluated and is now considered to be an important part of the overall treatment process. The standard treatment for newly diagnosed inflammatory breast cancer is to receive systemic therapy prior to surgery. Achieving no disease in the surgical samples gives the best prognosis. Surgery is modified radical mastectomy. Lumpectomy, segmentectomy, or skin sparing mastectomy is not recommended. Immediate reconstruction is not recommended. Upfront surgery is contraindicated. After surgery, all cases are recommended for radiation therapy unless it is contraindicated.

Because the aggressive nature of the disease, it is highly recommended to be seen by IBC specialist by a multidisciplinary team.

Further, it is critical to seek novel targeted therapy in a clinical trial setting. Three modalities, surgery, chemotherapy, and radiation are under-utilized in the USA. Estrogen and Progesterone receptor positive cases have not shown to have a better prognosis. Pathological complete response to preoperative chemotherapy imparts a more favorable prognosis than a pathologically incomplete response. Loss of heterozygosity and extensive breast inflammation upon first clinical examination have a significantly worse prognosis. Premenopausal cases have significantly worse prognosis. In postmenopausal cases lean women have significantly better prognosis than obese women. Among patients with distant metastasis at diagnosis (stage IV disease), The overall survival (OS) is worse in patients with IBC than in those with non-IBC.