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.

In breast cancer survivors, it is recommended to first consider non-hormonal options for menopausal effects, such as bisphosphonates or selective estrogen receptor modulators (SERMs) for osteoporosis, and vaginal estrogen for local symptoms. Observational studies of systemic hormone replacement therapy after breast cancer are generally reassuring. If hormone replacement is necessary after breast cancer, estrogen-only therapy or estrogen therapy with an intrauterine device with progestogen may be safer options than combined systemic therapy.

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.

In breast cancer survivors, non-hormonal birth control methods should be used as first-line options. Progestogen-based methods such as depot medroxyprogesterone acetate, IUD with progestogen or progestogen only pills have a poorly investigated but possible increased risk of cancer recurrence, but may be used if positive effects outweigh this possible risk.

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.

There are several treatment options for penile cancer, depending on staging. They include surgery, radiation therapy, chemotherapy, and biological therapy. The most common treatment is one of five types of surgery:

- Wide local excision—the tumor and some surrounding healthy tissue are removed

- Microsurgery—surgery performed with a microscope is used to remove the tumor and as little healthy tissue as possible

- Laser surgery—laser light is used to burn or cut away cancerous cells

- Circumcision—cancerous foreskin is removed

- Amputation (penectomy)—a partial or total removal of the penis, and possibly the associated lymph nodes.

Radiation therapy is usually used adjuvantly with surgery to reduce the risk of recurrence. With earlier stages of penile cancer, a combination of topical chemotherapy and less invasive surgery may be used. More advanced stages of penile cancer usually require a combination of surgery, radiation and chemotherapy.

In addition to all the above, treatment of the underlying disease like brucellosis, is important to limit disease recurrence.

Treatment of metastatic breast cancer is currently an active area of research. Several medications are in development or in phase I/II trials. Typically new medications and treatments are first tested in metastatic cancer before trials in primary cancer are attempted.

Another area of research is finding combination treatments which provide higher efficacy with reduced toxicity and side effects.

Experimental medications:

- sorafenib a combined Tyrosine protein kinases inhibitor.

Some patients with metastatic breast cancer opt to try alternative therapies such as vitamin therapy, homeopathic treatments, a macrobiotic diet, chiropractic or acupuncture. There is no evidence that any of these therapies are effective; they may be harmful, either because patients pass up effective conventional therapies such as chemotherapy or anti-estrogen therapy in favor of alternative treatments, or because the treatments themselves are harmful (as in the case of apricot-pit therapy—which exposes the patient to cyanide—or in chiropractic, which can be dangerous to patients with cancer metastatic to the spinal bones or spinal cord. A macrobiotic diet is neither effective nor safe as it could hypothetically induce weight loss due to severe dietary restriction. There is limited evidence that acupuncture might relive pain in cancer patients, but data so far is insufficient to recommend its use outside of clinical trials.

There is free peer support and an online platform to interact with others going through various therapies, including Abraxane.

Treatment largely follows patterns that have been set for the management of postmenopausal breast cancer. The initial treatment is surgical and consists of a modified radical mastectomy with axillary dissection or lumpectomy and radiation therapy with similar treatment results as in females. Also, mastectomy with sentinel lymph node biopsy is a treatment option. In males with node-negative tumors, adjuvant therapy is applied under the same considerations as in females with node-negative breast cancer. Similarly, with node-positive tumors, males increase survival using the same adjuvants as affected females, namely both chemotherapy plus tamoxifen and other hormonal therapy. There are no controlled studies in males comparing adjuvant options. In the vast majority of males with breast cancer hormone receptor studies are positive, and those situations are typically treated with hormonal therapy.

Locally recurrent disease is treated with surgical excision or radiation therapy combined with chemotherapy. Distant metastases are treated with hormonal therapy, chemotherapy, or a combination of both. Bones can be affected either by metastasis or weakened from hormonal therapy; bisphosphonates and calcitonin may be used to counterbalance this process and strengthen bones.

Many treatment options for cancer exist. The primary ones include surgery, chemotherapy, radiation therapy, hormonal therapy, targeted therapy and palliative care. Which treatments are used depends on the type, location and grade of the cancer as well as the patient's health and preferences. The treatment intent may or may not be curative.

Laser therapy uses high-intensity light to treat cancer by shrinking or destroying tumors or precancerous growths. Lasers are most commonly used to treat superficial cancers that are on the surface of the body or the lining of internal organs. It is used to treat basal cell skin cancer and the very early stages of others like cervical, penile, vaginal, vulvar, and non-small cell lung cancer. It is often combined with other treatments, such as surgery, chemotherapy, or radiation therapy. Laser-induced interstitial thermotherapy (LITT), or interstitial laser photocoagulation, uses lasers to treat some cancers using hyperthermia, which uses heat to shrink tumors by damaging or killing cancer cells. Laser are more precise than surgery and cause less damage, pain, bleeding, swelling, and scarring. A disadvantage is surgeons must have specialized training. It may be more expensive than other treatments.

Superficial tumors (those not entering the muscle layer) can be "shaved off" using an electrocautery device attached to a cystoscope, which in that case is called a resectoscope. The procedure is called transurethral resection of bladder tumor—TURBT—and serves primarily for pathological staging. In case of non-muscle invasive bladder cancer the TURBT is in itself the treatment, but in case of muscle invasive cancer, the procedure is insufficient for final treatment.

Immunotherapy by intravesicular delivery of Bacillus Calmette–Guérin (BCG) is also used to treat and prevent the recurrence of superficial tumors. BCG is a vaccine against tuberculosis that is prepared from attenuated (weakened) live bovine tuberculosis bacillus, Mycobacterium bovis, that has lost its virulence in humans. BCG immunotherapy is effective in up to 2/3 of the cases at this stage, and in randomized trials has been shown to be superior to standard chemotherapy. The mechanism by which BCG prevents recurrence is unknown, but the presence of bacteria in the bladder may trigger a localized immune reaction which clears residual cancer cells.

Patients whose tumors recurred after treatment with BCG are more difficult to treat. Many physicians recommend cystectomy for these patients. This recommendation is in accordance with the official guidelines of the European Association of Urologists (EAU) and the American Urological Association (AUA) However, many patients refuse to undergo this life changing operation, and prefer to try novel conservative treatment options before opting to this last radical resort. Device assisted chemotherapy is one such group of novel technologies used to treat superficial bladder cancer. These technologies use different mechanisms to facilitate the absorption and action of a chemotherapy drug instilled directly into the bladder. Another technology - electromotive drug administration (EMDA) – uses an electric current to enhance drug absorption after surgical removal of the tumor. Another technology, thermotherapy, uses radio-frequency energy to directly heat the bladder wall, which together with chemotherapy shows a synergistic effect, enhancing each other's capacity to kill tumor cells. This technology was studied by different investigators.

LCIS may be treated with close clinical follow-up and mammographic screening, tamoxifen or related hormone controlling drugs to reduce the risk of developing cancer, or bilateral prophylactic mastectomy. Some surgeons consider bilateral prophylactic mastectomy to be overly aggressive treatment except for certain high-risk cases.

Since Krukenberg tumors are secondary (metastatic), management might logically be driven by identifying and treating the primary cancer. The optimal treatment of Krukenberg tumors is unclear. The role of surgical resection has not been adequately addressed but if metastasis is limited to the ovaries, surgery may improve survival. The role of chemotherapy and/or radiotherapy is uncertain but may sometimes be beneficial.

Treatment methods include surgery, chemotherapy, radiation therapy and medication.

Standard treatment is surgery with adjuvant chemotherapy and radiotherapy. As a variation, neoadjuvant chemotherapy is very frequently used for triple-negative breast cancers. This allows for a higher rate of breast-conserving surgeries and by evaluating the response to the chemotherapy gives important clues about the individual responsiveness of the particular cancer to chemotherapy.

In addition to chemotherapy, an additive called Didox can be added to aid in the reduction of drug resistance and further treatment efforts. Didox is used to inhibit ribonucleotide reductase M2 (RRM2) which contributes to the cells resistance of the chemotherapy treatment resulting in a large number of relapse (Wilson 2016). RRM2 is upregulated within these specific Triple Negative cancer cells leading to a higher rate of drug resistance and inability to slow or stop the tumor progression which leads to more aggressive forms of triple negative breast cancer that are often fatal (Wilson 2016).

TNBCs are generally very susceptible to chemotherapy. In some cases, however, early complete response does not correlate with overall survival. This makes it particularly complicated to find the optimal chemotherapy. Adding a taxane to the chemotherapy appears to improve outcome substantially.

"BRCA1"-related triple-negative breast cancer appear to be particularly susceptible to chemotherapy including platinum-based agents and taxanes.

Although mutations in single genes were not individually predictive, TNBC tumors bearing mutations in genes involved in the androgen receptor (AR) and FOXA1 pathways were much more sensitive to chemotherapy. Mutations in the AR/FOXA1 pathway provide a novel marker for identifying chemosensitive TNBC patients who may benefit from current standard-of-care chemotherapy regimens. Mutations that lowered the levels of functional BRCA1 or BRCA2 RNA were associated with significantly better survival outcomes. This BRCA deficience signature define a new, highly chemosensitive subtype of TNBC. BRCA-deficient TNBC tumors have a higher rate of clonal mutation burden, defined as more clonal tumors with a higher number of mutations per clone, and are also associated with a higher level of immune activation, which may explain their greater chemosensitivity.

Angiogenesis and EGFR (HER-1) inhibitors are frequently tested in experimental settings and have shown efficacy. Treatment modalities are not sufficiently established for normal use, and it is unclear in which stage they are best used and which patients would profit.

By 2009 A number of new strategies for TNBC were being tested in clinical trials, including the PARP inhibitor BSI 201, NK012.

A novel antibody-drug conjugate known as Glembatumumab vedotin (CDX-011), which targets the protein GPNMB, has also shown encouraging clinical trial results in 2009.

PARP inhibitors had shown some promise in early trials but failed in some later trials.

Nov 2013: An accelerated approval Phase II clinical trial (METRIC) investigating glembatumumab vedotin versus capecitabine has begun, expected to enroll 300 patients with GPNMB-expressing metastatic TNBC.

Three early stage trials reported TNBC results in June 2016, for IMMU-132, Vantictumab, and atezolizumab in combination with the chemotherapy nab-paclitaxel.

Treatment of invasive carcinoma of no special type (NST) depends on the size of the mass (size of the tumor measured in its longest direction):

- <4 cm mass: surgery to remove the main tumor mass and to sample the lymph nodes in the axilla. The stage of the tumor is ascertained after this first surgery. Adjuvant therapy (i.e., treatment after surgery) may include a combination of chemotherapy, radiotherapy, hormonal therapy (e.g., tamoxifen) and/or targeted therapy (e.g., trastuzumab). More surgery is occasionally needed to complete the removal of the initial tumor or to remove recurrences.

- 4 cm or larger mass: modified (a less aggressive form of radical mastectomy) radical mastectomy (because any malignant mass in excess of 4 cm in size exceeds the criteria for a lumpectomy) along with sampling of the lymph nodes in the axilla.

The treatment options offered to an individual patient are determined by the form, stage and location of the cancer, and also by the age, history of prior disease and general health of the patient. Not all patients are treated the same way.

In order to address the problem of micrometastatic disease which in itself has implications on longtime survival, new treatment options are dearly needed. Micrometastatic dissemination is often not treatable with only major surgery and the concept of neoadjuvant chemotherapy has evolved. In this patients first receive chemotherapy in 3 or 4 cycles, and after that proceed to major surgery. In a number of meta-analyses of randomised prospective trials worldwide, the results have shown survival benefits between 5–8% with this therapy, in a follow up time of 5 years.

Treatment and survival is determined, to a great extent, by whether or not a cancer remains localized or spreads to other locations in the body. If the cancer metastasizes to other tissues or organs it usually dramatically increases a patient's likelihood of death. Some cancers—such as some forms of leukemia, a cancer of the blood, or malignancies in the brain—can kill without spreading at all.

Once a cancer has metastasized it may still be treated with radiosurgery, chemotherapy, radiation therapy, biological therapy, hormone therapy, surgery, or a combination of these interventions ("multimodal therapy"). The choice of treatment depends on a large number of factors, including the type of primary cancer, the size and location of the metastases, the patient's age and general health, and the types of treatments used previously. In patients diagnosed with CUP it is often still possible to treat the disease even when the primary tumor cannot be located.

Current treatments are rarely able to cure metastatic cancer though some tumors, such as testicular cancer and thyroid cancer, are usually curable.

Palliative care, care aimed at improving the quality of life of people with major illness, has been recommended as part of management programs for metastasis.

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.

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.

CUP is a term that refers to many different cancers. For that reason, treatment depends on where the cancer is found, the microscopic appearance of the cancer cells, the biochemical characterization of the cells, and the patient’s age and overall physical condition. In women, who present with axillary lymph node involvement, treatment is offered along the lines of breast cancer. In patients, who have neck lymph node involvement, then treatment is offered along the lines of head and neck cancer. If inguinal lymph nodes are involved, then treatment may be offered along the lines of genitourinary cancer.

If the site of origin is unknown or undiscovered, then the histology of the tumor (e.g., adenocarcinoma, squamous cell or mesenchymal) can usually be identified, and a probable origin may be assumed. When this is possible, then treatment is based on the type of cell and probable origin. Based on histological subtype, combination chemotherapy may be selected. A combination of carboplatin and paclitaxel is often used. Advances techniques such as FISH and tissue of origin testing may also be employed. Germ cell tumors often carry abnormality of chromosome 12, which if identified, directs treatment for metastatic germ cell tumors.

No method is standard for all forms of CUP, but chemotherapy, radiation therapy, hormone therapy, and surgery may be used alone or in combination to treat patients who have CUP. Even when the cancer is unlikely to be cured, treatment may help the patient live longer or improve the patient’s quality of life. Radiation may be used to shrink a variety of local tumors. However, the potential side effects of the treatment must be considered along with the potential benefits.

In CUP to secondary neck nodes, surgery followed by external beam radiotherapy is sufficient.

For CUP with an unfavorable prognosis, treatment with taxanes may provide a slight survival benefit. The uncertainties and ambiguity inherent in a CUP diagnosis may cause additional stress for the patient.

Carcinoma "in situ" is, by definition, a localized phenomenon, with no potential for metastasis unless it progresses into cancer. Therefore, its removal eliminates the risk of subsequent progression into a life-threatening condition.

Some forms of CIS (e.g., colon polyps and polypoid tumours of the bladder) can be removed using an endoscope, without conventional surgical resection. Dysplasia of the uterine cervix is removed by excision (cutting it out) or by burning with a laser. Bowen's disease of the skin is removed by excision. Other forms require major surgery, the best known being intraductal carcinoma of the breast (also treated with radiotherapy). One of the most dangerous forms of CIS is the "pneumonic form" of BAC of the lung, which can require extensive surgical removal of large parts of the lung. When too large, it often cannot be completely removed, with eventual disease progression and death of the patient.

Prognosis can range considerably for patients, depending where on the scale they have been staged. Generally speaking, the earlier the cancer is diagnosed, the better the prognosis. The overall 5-year survival rate for all stages of penile cancer is about 50%.