80% of cases in the United States are diagnosed by mammography screening.

There are many diagnostic methods that can be used to determine the type of salivary gland tumour and if it is benign or malignant. Examples of diagnostic methods include:

Physical exam and history: An exam of the body to check general signs of health. The head, neck, mouth, and throat will be checked for signs of disease, such as lumps or anything else that seems unusual. A history of the patient's health habits and past illnesses and treatments will also be taken.

Endoscopy: A procedure to look at organs and tissues inside the body to check for abnormal areas. For salivary gland cancer, an endoscope is inserted into the mouth to look at the mouth, throat, and larynx. An endoscope is a thin, tube-like instrument with a light and a lens for viewing.

MRI

Biopsy: The removal of cells or tissues so they can be viewed under a microscope by a pathologist to check for signs of cancer.

Fine needle aspiration (FNA) biopsy: The removal of tissue or fluid using a thin needle. An FNA is the most common type of biopsy used for salivary gland cancer, and has been shown to produce accurate results when differentiating between benign and malignant tumours.

Radiographs: An OPG (orthopantomogram) can be taken to rule out mandibular involvement. A chest radiograph may also be taken to rule out any secondary tumours.

Ultrasound: Ultrasound can be used to initially assess a tumour that is located superficially in either the submandibular or parotid gland. It can distinguish an intrinsic from an extrinsic neoplasm. Ultrasonic images of malignant tumours include ill defined margins.

Lesions of the nipple and areola, such as nipple adenoma, may be difficult to image clearly on routine mammogram or ultrasonography. Nipple adenomas can be imaged using magnetic resonance imaging (MRI) and conventional or MR ductogram.

Breast cancer screening refers to testing otherwise-healthy women for breast cancer in an attempt to achieve an earlier diagnosis under the assumption that early detection will improve outcomes. A number of screening tests have been employed including clinical and self breast exams, mammography, genetic screening, ultrasound, and magnetic resonance imaging.

A clinical or self breast exam involves feeling the breast for lumps or other abnormalities. Clinical breast exams are performed by health care providers, while self-breast exams are performed by the person themselves. Evidence does not support the effectiveness of either type of breast exam, as by the time a lump is large enough to be found it is likely to have been growing for several years and thus soon be large enough to be found without an exam. Mammographic screening for breast cancer uses X-rays to examine the breast for any uncharacteristic masses or lumps. During a screening, the breast is compressed and a technician takes photos from multiple angles. A general mammogram takes photos of the entire breast, while a diagnostic mammogram focuses on a specific lump or area of concern.

A number of national bodies recommend breast cancer screening. For the average woman, the U.S. Preventive Services Task Force recommends mammography every two years in women between the ages of 50 and 74, the Council of Europe recommends mammography between 50 and 69 with most programs using a 2-year frequency, and in Canada screening is recommended between the ages of 50 and 74 at a frequency of 2 to 3 years. These task force reports point out that in addition to unnecessary surgery and anxiety, the risks of more frequent mammograms include a small but significant increase in breast cancer induced by radiation.

The Cochrane collaboration (2013) states that the best quality evidence neither demonstrates a reduction in cancer specific, nor a reduction in all cause mortality from screening mammography. When less rigorous trials are added to the analysis there is a reduction in mortality due to breast cancer of 0.05% (a decrease of 1 in 2000 deaths from breast cancer over 10 years or a relative decrease of 15% from breast cancer). Screening over 10 years results in a 30% increase in rates of over-diagnosis and over-treatment (3 to 14 per 1000) and more than half will have at least one falsely positive test. This has resulted in the view that it is not clear whether mammography screening does more good or harm. Cochrane states that, due to recent improvements in breast cancer treatment, and the risks of false positives from breast cancer screening leading to unnecessary treatment, "it therefore no longer seems beneficial to attend for breast cancer screening" at any age. Whether MRI as a screening method has greater harms or benefits when compared to standard mammography is not known.

The appropriate treatment in contemporary western medicine is complete surgical excision of the abnormal growth with a small amount of normal surrounding breast tissue.

Multiple imaging modalities may be necessary to evaluate abnormalities of the nipple-areolar complex.

In two studies performed in Japan, high-resolution MRI with a microscopy coil yielding 0.137-mm in-plane resolution has been used to confirm the presence of abscesses, isolated fistulas and inflammation and to reveal their position in order to guide surgery.

A fibroadenoma is usually diagnosed through clinical examination, ultrasound or mammography, and often a needle biopsy sample of the lump.

The selective estrogen receptor modulators (such as tamoxifen) reduce the risk of breast cancer but increase the risk of thromboembolism and endometrial cancer. There is no overall change in the risk of death. They are thus not recommended for the prevention of breast cancer in women at average risk but may be offered for those at high risk. The benefit of breast cancer reduction continues for at least five years after stopping a course of treatment with these medications.

The diagnosis of nipple discharge will be determined upon an examination by a health provider who will ask questions about symptoms and medical history. Tests that may be done include:

- Prolactin blood test

- Thyroid blood tests

- Head CT scan or MRI to look for pituitary tumor

- Mammography

- Ultrasound of the breast

- Breast biopsy

- Ductography or ductogram: an x-ray with contrast dye injected into the affected milk duct

- Skin biopsy, if Paget disease is a concern

Intraductal papillomas of the breast are benign lesions with an incidence of approximately 2-3% in humans.

Two types of intraductal papillomas are generally distinguished. The central type develops near the nipple. They are usually solitary and often arise in the period nearing menopause. On the other hand, the peripheral type are often multiple papillomas arising at the peripheral breasts, and are usually found in younger women. The peripheral type are associated with a higher risk of malignancy.

They are the most common cause of bloody nipple discharge in women age 20-40 and generally do not show up on mammography due to their small size. They may be detectable on ultrasound. A galactogram is the most definitive test but is somewhat invasive.

The masses are often too small to be palpated or felt. A galactogram is therefore necessary to rule out the lesion.

Excision is sometimes performed. Microdochectomy/microdochotomy (removal of a breast duct) is the treatment of choice.

The FDA has approved cryoablation of a fibroadenoma as a safe, effective and minimally-invasive alternative to open surgical removal in 2001. In the procedure, ultrasound imaging is used to guide a probe into the mass of breast tissue. Extremely cold temperatures are then used to destroy the abnormal cells, and over time the cells are reabsorbed into the body. The procedure can be performed as an outpatient surgery using local anesthesia only, and leaves substantially less scarring than open surgical procedures and no breast tissue deformation.

The American Society of Breast Surgeons recommends the following criteria to establish a patient as a candidate for cryoablation of a fibroadenoma:

1. The lesion must be sonographically visible.

2. The diagnosis of a fibroadenoma must be confirmed histologically.

3. The lesion should be less than 4 cm in diameter.

Because DCIS is normally found early and it is treated or managed, it is difficult to say what occurs if left untreated. About 2% of women who are diagnosed with this condition and treated died within 10 years. Biomarkers can identify which women who were initially diagnosed with DCIS are at high or low risk of subsequent invasive cancer.

Most of the time, nipple problems are not breast cancer. These problems will either go away with the right treatment, or they can be watched closely over time.

The condition is usually self-limiting, and thus not indicated for surgery.

Note: differentiation is done accurately by microscopic examination only.

The term "duct ectasia syndrome" has been used to describe symptoms of nonpuerperal mastitis, possibly associated with nipple inversion and nipple discharge. In some contexts, it was used to describe a particular form of nonpuerperal mastitis coincident with fibrocystic disease, frequently involving pasty (coloured) nipple discharge, nipple retraction, retroareolar abscess and blue dome cysts. Abscessation is not very frequent but by some definitions recurrent subareolar abscess is merely a variant of duct ectasia syndrome - abscessation would be obviously more frequent with this definition.

Duct ectasia syndrome has been associated with histopathological findings that are distinct from a simple duct widening. In addition to nonspecific duct widening the myoepithelial cell layer is atrophic, missing or replaced by fibrous tissue. The original cuboidal epithelial layer may be also severely impaired or missing. Characteristic calcifications are often visible on mammographic images.

Periductal mastitis, comedo mastitis, secretory disease of the breast, plasma cell mastitis and mastitis obliterans are sometimes considered special cases or synonyms of duct ectasia syndrome.

Inverted papillomas are definitively diagnosed by histologic examination. However, Magnetic Resonanace Imaging (MRI) may show a characteristic feature described as a Convoluted Cerebriform Pattern (CCP). A retrospective study published in the American Journal of Neuroradiology concluded that identification of CCP by MRI in a patient with a nasal tumor made the diagnosis of Inverted papilloma quite likely. The study reported the sensitivity and specificity to be 100% and 87% respectively. CCP can be associated with other malignant tumors as well.

According to the NIH Consensus Conference , if DCIS is allowed to go untreated, the natural course or natural history varies according to the grade of the DCIS. Unless treated, approximately 60 percent of low-grade DCIS lesions will have become invasive at 40 years follow-up. High-grade DCIS lesions that have been inadequately resected and not given radiotherapy have a 50 percent risk of becoming invasive breast cancer within seven years. Approximately half of low-grade DCIS detected at screening will represent overdiagnosis, but overdiagnosis of high-grade DCIS is rare. The natural history of intermediate-grade DCIS is difficult to predict. Approximately one-third of malignant calcification clusters detected at screening mammography already have an invasive focus.

The prognosis of IDC depends, in part, on its histological subtype. Mucinous, papillary, cribriform, and tubular carcinomas have longer survival, and lower recurrence rates. The prognosis of the most common form of IDC, called "IDC Not Otherwise Specified", is intermediate. Finally, some rare forms of breast cancer (e.g., sarcomatoid carcinoma, inflammatory carcinoma) have a poor prognosis. Regardless of the histological subtype, the prognosis of IDC depends also on tumor size, presence of cancer in the lymph nodes, histological grade, presence of cancer in small vessels (vascular invasion), expression of hormone receptors and of oncogenes like HER2/neu.

These parameters can be entered into models that provide a statistical probability of systemic spread. The probability of systemic spread is a key factor in determining whether radiation and chemotherapy are worthwhile. The individual parameters are important also because they can predict how well a cancer will respond to specific chemotherapy agents.

Overall, the 5-year survival rate of invasive ductal carcinoma was approximately 85% in 2003.

Treatment may include the following:

- Surgery with or without radiation

- Radiotherapy

Fast neutron therapy has been used successfully to treat salivary gland tumors, and has shown to be significantly more effective than photons in studies treating unresectable salivary gland tumors.

- Chemotherapy

Ultrasound is the often chosen to examine the duct and determine the presence and size of any cysts or abnormalities. Fine-needle aspiration cytology can also be used to confirm the diagnosis.

SDC are diagnosed by examination of tissue, e.g. a biopsy.

Their histologic appearance is similar to ductal breast carcinoma.

While most cases require no treatment, therapy options include cryotherapy, application of a topical salicylic acid compound, surgical and laser ablation.

Treatment is problematic unless an underlying endocrine disorder can be successfully diagnosed and treated.

A study by Goepel and Panhke provided indications that the inflammation should be controlled by bromocriptine even in absence of hyperprolactinemia.

Antibiotic treatment is given in case of acute inflammation. However, this alone is rarely effective, and the treatment of a subareaolar abscess is primarily surgical. In case of an acute abscess, incision and drainage are performed, followed by antibiotics treatment. However, in contrast to peripheral breast abscess which often resolves after antibiotics and incision and drainage, subareaolar breast abscess has a tendency to recur, often accompanied by the formation of fistulas leading from inflammation area to the skin surface. In many cases, in particular in patients with recurrent subareolar abscess, the excision of the affected lactiferous ducts is indicated, together with the excision of any chronic abscess or fistula. This can be performed using radial or circumareolar incision.

There is no universal agreement on what should be the standard way of treating the condition. In a recent review article, antibiotics treatment, ultrasound evaluation and, if fluid is present, ultrasound-guided fine needle aspiration of the abscess with an 18 gauge needle, under saline lavage until clear, has been suggested as initial line of treatment for breast abscess in puerperal and non-puerperal cases including central (subareolar) abscess (see breast abscess for details). Elsewhere, it has been stated that treatment of subareolar abscess is unlikely to work if it does not address the ducts as such.

Duct resection has been traditionally used to treat the condition; the original Hadfield procedure has been improved many times but long term success rate remains poor even for radical surgery. Petersen even suggests that damage caused by previous surgery is a frequent cause of subareolar abscesses. Goepel and Pahnke and other authors recommend performing surgeries only with concomitant bromocriptine treatment.

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.

Diagnosis is usually made by characteristic history and physical examination. Diagnosis can be confirmed by x-ray (80% of salivary gland calculi are visible on x-ray), by sialogram, or by ultrasound.