Most of the women who develop DCIS do not experience any symptoms. The majority of cases (80-85%) are detected through screening mammography. The first signs and symptoms may appear if the cancer advances. Because of the lack of early symptoms, DCIS is most often detected at screening mammography.

In a few cases, DCIS may cause:

- A lump or thickening in or near the breast or under the arm

- A change in the size or shape of the breast

- Nipple discharge or nipple tenderness; the nipple may also be inverted, or pulled back into the breast

- Ridges or pitting of the breast; the skin may look like the skin of an orange

- A change in the way the skin of the breast, areola, or nipple looks or feels such as warmth, swelling, redness or scaliness.

In many cases, ductal carcinoma is asymptomatic, and detected as abnormal results on mammography. When symptoms occur, a painless, enlarging mass that does not fluctuate with the menstrual period may be felt. Pinching of the overlying skin may also be seen. Certain subtypes, such as inflammatory carcinomas, may result in a swollen, enlarged and tender breast. All variants of cancer, if there is metastatic spread, may cause enlarged lymph nodes and affect other organs.

The typical presentation is a rapidly growing mass with associated pain. This may be seen in association with neck lymph node swelling (cervical lymphadenopathy), due to metastases, and facial nerve paralysis.

Invasive carcinoma of no special type (NST) is the most common form of invasive breast cancer. It accounts for 55% of breast cancer incidence upon diagnosis, according to statistics from the United States in 2004. On a mammogram, it is usually visualized as a mass with fine spikes radiating from the edges. On physical examination, this lump usually feels much harder or firmer than benign breast lesions such as fibroadenoma. On microscopic examination, the cancerous cells invade and replace the surrounding normal tissues. IDC is divided in several histological subtypes.

Lobular carcinoma "in situ" (LCIS) is a condition caused by unusual cells in the lobules of the breast.

Many do not consider it cancer, but it can indicate an increased risk of future cancer. The national database registrars, however, consider it a malignancy.

Unlike ductal carcinoma "in situ" (DCIS), LCIS is not associated with calcification, and is typically an incidental finding in a biopsy performed for another reason. LCIS only accounts for about 15% of the "in situ" (ductal or lobular) breast cancers.

Ductal carcinoma in situ (DCIS), also known as intraductal carcinoma, is a pre-cancerous or non-invasive cancerous lesion of the breast. DCIS is classified as Stage 0. It rarely produces symptoms or a breast lump one can feel, and is usually detected through screening mammography.

In DCIS, abnormal cells are found in the lining of one or more milk ducts in the breast. "In situ" means "in place" and refers to the fact that the abnormal cells have not moved out of the mammary duct and into any of the surrounding tissues in the breast ("pre-cancerous" refers to the fact that it has not yet become an invasive cancer). In some cases, DCIS may become invasive and spread to other tissues, but there is no way of determining which lesions will remain stable without treatment, and which will go on to become invasive. DCIS encompasses a wide spectrum of diseases ranging from low-grade lesions that are not life-threatening to high-grade (i.e. potentially highly aggressive) lesions.

DCIS has been classified according to the architectural pattern of the cells (solid, cribriform, papillary, and micropapillary), tumor grade (high, intermediate, and low grade), and the presence or absence of comedo histology. DCIS can be detected on mammograms by examining tiny specks of calcium known as microcalcifications. Since suspicious groups of microcalcifications can appear even in the absence of DCIS, a biopsy may be necessary for diagnosis.

About 20–30% of those who do not receive treatment develop breast cancer. It is the most common type of pre-cancer in women. There is some disagreement as to whether, for statistical purposes, it should be counted as a cancer: some include DCIS when calculating breast cancer statistics while others do not.

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

Their histologic appearance is similar to ductal breast carcinoma.

Uterine serous carcinoma (USC), also known as uterine papillary serous carcinoma (UPSC) and uterine serous adenocarcinoma, is an uncommon form of endometrial cancer that typically arises in postmenopausal women.

It is typically diagnosed on endometrial biopsy, prompted by post-menopausal bleeding.

Unlike the more common low-grade "endometrioid endometrial adenocarcinoma", USC does not develop from endometrial hyperplasia and is not hormone-sensitive. It arises in the setting of endometrial atrophy and is classified as a type II endometrial cancer.

Atypical ductal hyperplasia, abbreviated ADH, is the term used for a benign lesion of the breast that indicates an increased risk of breast cancer.

The name of the entity is descriptive of the lesion; ADH is characterized by cellular proliferation (hyperplasia) within one or two breast ducts and (histomorphologic) architectural abnormalities, i.e. the cells are arranged in an abnormal or atypical way.

In the context of a core (needle) biopsy, ADH is considered an indication for a breast lumpectomy, also known as a surgical (excisional) biopsy, to exclude the presence of breast cancer.

Invasive lobular carcinoma accounts for 5-10% of invasive breast cancer.

The histologic patterns include:

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

Loss of E-cadherin is common in lobular carcinoma but is also seen in other breast cancers.

Treatment includes surgery and adjuvant therapy.

These terms are related since they represent the steps of the progression toward cancer:

- Dysplasia is the earliest form of precancerous lesion recognizable in a biopsy. Dysplasia can be low-grade or high-grade. High-grade dysplasia may also be referred to as carcinoma "in situ".

- Invasive carcinoma, usually simply called cancer, has the potential to invade and spread to surrounding tissues and structures, and may eventually be lethal.

Adenoid cystic carcinoma (sometimes referred to as adenocyst, malignant cylindroma, adenocystic, adenoidcystic, ACC or AdCC.) is a rare type of cancer that can exist in many different body sites. This tumor most often occurs in the salivary glands, but it can also be found in many anatomic sites, including the breast, lacrimal gland, lung, brain, bartholin gland, trachea, and the paranasal sinuses.

It is the third most common malignant salivary gland tumor overall (after mucoepidermoid carcinoma and polymorphous low grade adenocarcinoma). It represents 28% of malignant submandibular gland tumors, making it the single most common malignant salivary gland tumor in this region. Patients may survive for years with metastases because this tumor is generally well-differentiated and slow growing. In a 1999 study of a cohort of 160 ACC patients, disease specific survival was 89% at 5 years but only 40% at 15 years, reflecting deaths from late-occurring metastatic disease.

Adenocarcinoma (; plural adenocarcinomas or adenocarcinomata ) is a type of cancerous tumor that can occur in several parts of the body. It is defined as neoplasia of epithelial tissue that has glandular origin, glandular characteristics, or both. Adenocarcinomas are part of the larger grouping of carcinomas, but are also sometimes called by more precise terms omitting the word, where these exist. Thus invasive ductal carcinoma, the most common form of breast cancer, is adenocarcinoma but does not use the term in its name—however, esophageal adenocarcinoma does to distinguish it from the other common type of esophageal cancer, esophageal squamous cell carcinoma. Several of the most common forms of cancer are adenocarcinomas, and the various sorts of adenocarcinoma vary greatly in all their aspects, so that few useful generalizations can be made about them.

In the most specific usage (narrowest sense), the glandular origin or traits are exocrine; endocrine gland tumors, such as a VIPoma, an insulinoma, or a pheochromocytoma, are typically not referred to as adenocarcinomas but rather are often called neuroendocrine tumors. Epithelial tissue sometimes includes, but is not limited to, the surface layer of skin, glands, and a variety of other tissue that lines the cavities and organs of the body. Epithelial tissue can be derived embryologically from any of the germ layers (ectoderm, endoderm, or mesoderm). To be classified as adenocarcinoma, the cells do not necessarily need to be part of a gland, as long as they have secretory properties. Adenocarcinoma is the malignant counterpart to adenoma, which is the benign form of such tumors. Sometimes adenomas transform into adenocarcinomas, but most do not.

Well differentiated adenocarcinomas tend to resemble the glandular tissue that they are derived from, while poorly differentiated adenocarcinomas may not. By staining the cells from a biopsy, a pathologist can determine whether the tumor is an adenocarcinoma or some other type of cancer. Adenocarcinomas can arise in many tissues of the body owing to the ubiquitous nature of glands within the body, and, more fundamentally, to the potency of epithelial cells. While each gland may not be secreting the same substance, as long as there is an exocrine function to the cell, it is considered glandular and its malignant form is therefore named adenocarcinoma.

Radial scars are diagnosed by a microscopic examination of excised tissue, i.e. they are diagnosed by pathologists based on their histomorphology.

The lesion is found in patients who present typically with abnormal or postmenopausal bleeding. Such bleeding is followed by further evaluation leading to a tissue diagnosis, usually done by a dilatation and curettage (D&C). A work-up to follow would look for metastasis using imaging technology including sonography and MRI. The median age at diagnosis in a study of 138 women was 67 years, of these 54 had stage I, 20 stage II, 41 stage III, and 23 stage IV disease.

Histopathologically, uterine serous carcinomas is typically characterized by (1) nipple-shaped structures (papillae) with fibrovascular cores (2) marked nuclear atypia (irregularies in the nuclear membrane, enlarged nuclear size), (3) psammoma bodies and (4) cilia.

Carcinoma "in situ (CIS), also known as in situ" neoplasm, is a group of abnormal cells. While they are a form of neoplasm there is disagreement over whether CIS should be classified as cancer. This controversy also depends on the exact CIS in question (i.e. cervical, skin, breast). Some authors do not classify them as cancer, however, recognizing that they can potentially become cancer. Others classify certain types as a non-invasive form of cancer. The term "pre-cancer" has also been used.

These abnormal cells grow in their normal place, thus ""in situ"" (from Latin for "in its place"). For example, carcinoma "in situ" of the skin, also called Bowen's disease, is the accumulation of dysplastic epidermal cells within the epidermis only, that has failed to penetrate into the deeper dermis. For this reason, CIS will usually not form a tumor. Rather, the lesion is flat (in the skin, cervix, etc.) or follows the existing architecture of the organ (in the breast, lung, etc.). Exceptions include CIS of the colon (polyps), the bladder (preinvasive papillary cancer), or the breast (ductal carcinoma "in situ" or lobular carcinoma "in situ").

Many forms of CIS have a high probability of progression into cancer, and therefore removal may be recommended; however, progression of CIS is known to be highly variable and not all CIS becomes invasive cancer.

In the TNM classification, carcinoma "in situ" is reported as TisN0M0 (stage 0).

Krukenberg tumors often come to the attention when they cause abdominal or pelvic pain, bloating, ascites, or pain during sexual intercourse. Krukenberg tumors can occasionally provoke a reaction of the ovarian stroma which leads to hormone production, that results in vaginal bleeding, a change in menstrual habits, or hirsutism, or occasionally virilization as a main symptom.

All these symptoms are non-specific and can also arise with a range of problems other than cancer, and a diagnosis can only be made following confirmatory investigations such as computed tomography (CT) scans, laparotomy and/or a biopsy of the ovary.

ADH, generally, is asymptomatic. It usually comes to medical attention on a screening mammogram, as a non-specific suspicious abnormality that requires a biopsy.

In breast pathology, a radial scar of the breast, formally radial scar of the breast, is a benign breast lesion that can radiologically mimic malignancy, i.e. cancer.

Radial scar is associated with atypia and/or malignancy and may be an independent risk factor for the development of carcinoma in either breast.

An adenomyoepithelioma of the breast, also adenomyoepithelioma, is a rare tumour in the breast composed of glandular elements (adeno-) and myoepithelial cells. It is usually benign; however, there are reports of malignant behaviour.

The histomorphologic appearance can mimic invasive ductal carcinoma, the most common type of invasive breast cancer.

Basophilic, bland cells similar to acinar cells. Growth pattern: solid - acinar cells, microcytic - small systic spaces mucinous or eosinophilic, papillary-cystic - large cystic lined by epithelium, follicular - similar to thyroid tissue.

These tumors which resemble serous acinar cells vary in their behavior from locally aggressive to blatantly malignant.

It can also appear in the breast. The pancreatic form of acinic cell carcinoma is a rare subtype of exocrine pancreatic cancer. Exocrine pancreatic cancers are the most common form of pancreatic cancer when compared to endocrine pancreatic cancer.

Acinic cell carcinomas arise most frequently in the parotid gland. Other sites of primary tumors have included the submandibular gland and other major and minor salivary glands. There have been rare cases of primary tumors involving the parapharyngeal space and the sublingual gland.

Nipple adenomas may be felt as a lump under the nipple or areola. They may come to attention because of nipple pain, ulceration, swelling or discharge.

Like the cells of atypical lobular hyperplasia and invasive lobular carcinoma, the abnormal cells of LCIS consist of small cells with oval or round nuclei and small nucleoli detached from each other. Mucin-containing signet-ring cells are commonly seen. LCIS generally leaves the underlying architecture intact and recognisable as lobules. Estrogen and progesterone receptors are present and HER2/neu overexpression is absent in most cases of LCIS.

Acinic cell carcinoma is a malignant tumor representing 2% of all salivary tumors. 90% of the time found in the parotid gland, 10% intraorally on buccal mucosa or palate. The disease presents as a slow growing mass, associated with pain or tenderness in 50% of the cases. Often appears pseudoencapsulated.

Medullary carcinoma may refer to one of several different tumors of epithelial origin. As the term "" is a generic anatomic descriptor for the mid-layer of various organ tissues, a medullary tumor usually arises from the "mid-layer tissues" of the relevant organ.

Medullary carcinoma most commonly refers to:

- Medullary thyroid cancer

- Medullary carcinoma of the breast

Medullary carcinoma may also refer to tumors of:

- Pancreas

- Ampulla of Vater

- Gallbladder

- Stomach

- Large intestine

- Kidney — Renal medullary carcinoma