Cytologic features of serous carcinoma are:

- Marked intragroup nuclear pleomorphism.

- Macronucleoli.

- "Knobby" group borders (in large groups).

- Hydropic vacuoles.

Symptoms of serous carcinoma may include:

- Discomfort/pain or bloating in abdomen

- Frequent urination

- Weight loss

Hidradenoma (also known as acrospiroma, from "akral ""peripheral"" + spiroma ""epithelial tumor of sweat gland") refers to a benign adnexal tumor of the apical sweat gland. Another name for Hidradenoma is Cystadenoma and Hydrocystadenomas. These are 1–3 cm translucent blue cystic nodules.It usually presents as a single, small skin-colored lesion, and is considered distinct from the closely related poroma. Hidradenomas are often sub-classified based on subtle histologic differences, for example:

- clear-cell hidradenoma or acrospiroma

- nodular hidradenoma or acrospiroma

- solid-cystic hidradenoma

Discussion of sweat gland tumors can be difficult and confusing due to the complex classification and redundant terminology used to describe the same tumors. For example, acrospiroma and hidradenoma are synonymous, and sometimes the term "acrospiroma" is used to generally describe benign sweat gland tumors. In addition, a single lesion may contain a mixture of cell-types. There has also been a change in understanding about how tumors that were previously believed to strictly derive from specific sweat gland types may, in fact, derive from both eccrine "or" apocrine glands.

Hidradenomas are by definition benign, with malignant transformation very rare. When tumors show malignant characteristics, they are known as hidradenocarcinoma. Surgical excision is usually curative and local recurrences are rare, although malignant tumors may metastasize.

Hidradenocarcinoma (also known as malignant hidradenoma, malignant acrospiroma, clear cell eccrine carcinoma, or primary mucoepidermoid cutaneous carcinoma) is a malignant adnexal tumor of the sweat gland. It is the malignant variant of the benign hidradenoma. It may develop de novo or in association with an existent hidradenoma.

This type of tumor typically develops in older individuals (after age 40).

In pathology, serous carcinoma is an epithelial malignancy (carcinoma) that arises from the lining of a cavity that produces a serum-like fluid (a serous cavity).

Serous lined cavities include the peritoneum, pericardium and pleural space and tunica vaginalis.

A basaloid follicular hamartoma is a cutaneous condition characterized as distinctive benign adnexal tumor that has several described variants.

Ductal carcinoma is a type of tumor that primarily presents in the ducts of a gland.

Types include:

- Mammary

- Ductal carcinoma in situ

- Invasive ductal carcinoma

- Pancreatic ductal carcinoma

Due to the diverse nature of salivary gland tumours, many different terms and classification systems have been used. Perhaps the most widely used currently is that system proposed by the World Health Organization in 2004, which classifies salivary neoplasms as primary or secondary, benign or malignant, and also by tissue of origin. This system defines five broad categories of salivary gland neoplasms:

Benign epithelial tumors

- Pleomorphic adenoma

- Warthin's tumor

- Myoepithelioma

- Basal cell adenoma

- Oncocytoma

- Canalicular adenoma

- Lymphadenoma

- "Sebaceous lymphadenoma"

- "Nonsebaceous lymphadenoma"

- Ductal papilloma

- "Inverted ductal papilloma"

- "Intraductal papilloma"

- "Sialadenoma papilliferum"

- Cystadenoma

- Malignant epithelial tumors

- Acinic cell carcinoma

- Mucoepidermoid carcinoma

- Adenoid cystic carcinoma

- Polymorphous low-grade adenocarcinoma

- Epithelial-myoepithelial carcinoma

- Clear cell carcinoma, not otherwise specified

- Basal cell adenocarcinoma

- Sebaceous carcinoma

- Sebaceous lymphadenocarcinoma

- Cystadenocarcinoma

- Low-grade cribriform cystadenocarcinoma

- Mucinous adenocarcinoma

- Oncocytic carcinoma

- Salivary duct carcinoma

- Salivary duct carcinoma, not otherwise specified

- Adenocarcinoma, not otherwise specified

- Myoepithelial carcinoma

- Carcinoma ex pleomorphic adenoma

- Mammary analogue secretory carcinoma

- Carcinosarcoma

- Metastasizing pleomorphic adenoma

- Squamous cell carcinoma

- Large cell carcinoma

- Lymphoepithelial carcinoma

- Sialoblastoma

- Soft tissue tumors

- Hemangioma

- Hematolymphoid tumors

- Hodgkin lymphoma

- Diffuse large B-cell lymphoma

- Extranodal marginal zone B cell lymphoma

- Secondary tumors (i.e. a tumor which has metastasized to the salivary gland from a distant location)

Others, not included in the WHO classification above, include:

- Intraosseous (central) salivary gland tumors

- Hybrid tumors (i.e. a tumor displaying combined forms of histologic tumor types)

- Hybrid carcinoma

- Others

- Others

- Keratocystoma

- Sialolipoma

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.

Serous cystadenocarcinoma is a type of tumor in the cystadenocarcinoma grouping.

Most commonly the primary site of serous cystadenocarcinoma is the ovary. Rare occurrence in the pancreas has been reported, although this is not typical, with the majority of microcystic pancreatic masses representing alternate disease processes such as the more benign serous cystadenoma.

Salivary gland tumours usually present as a lump or swelling in the affected gland which may or may not have been present for a long time. The lump may be accompanied by symptoms of duct blockage (e.g. xerostomia). Usually, in their early stages it is not possible to distinguish a benign tumour from a malignant one. One of the key differentiating symptoms of a malignant growth is nerve involvement. For example signs of facial nerve damage (e.g facial palsy) are associated with malignant parotid tumours. Facial pain, and paraesthesia are also very often associated with a malignant tumours. Other red flag symptoms which may suggest malignancy and warrant further investigation are fixation of the lump to the overlying skin, ulceration and induration of the mucosa.

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.

Microcystic adnexal carcinoma (also known as sclerosing sweat duct carcinoma) is a cutaneous condition characterized by a slow-growing plaque or nodule.

Sebaceous carcinoma is an uncommon and aggressive malignant cutaneous tumor. Most are typically about 10 mm in size at presentation. This neoplasm is thought to arise from sebaceous glands in the skin and, therefore, may originate anywhere in the body where these glands are found. Because the periocular region is rich in this type of gland, this region is a common site of origin. The cause of these lesions are, in the vast majority of cases, unknown. Occasional cases may be associated with Muir-Torre syndrome.

This type of cancer usually has a poor prognosis because of a high rate of metastasis.

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).

Primary peritoneal cancer or carcinoma is also known as serous surface papillary carcinoma, primary peritoneal carcinoma, extra-ovarian serous carcinoma, primary serous papillary carcinoma, psammomacarcinoma. It was historically classified under "carcinoma of unknown primary" (CUP). Primary peritoneal cancer (PPC, or PPCa) is a cancer of the cells lining the peritoneum, or abdominal cavity.

Some studies indicate that up to 15% of serous ovarian cancers are thought to be actually primary peritoneal carcinomas in origin.

Histomorphological and molecular biological characteristics suggest that serous carcinomas, which include ovarian serous carcinoma, uterine serous carcinoma, Fallopian tube serous carcinoma, cervical serous carcinoma, and primary peritoneal serous carcinoma really represent one entity.

Lymphoepithelioma-like carcinoma (LELC) is a medical term referring to a histological variant of malignant tumor arising from the uncontrolled mitosis of transformed cells originating in epithelial tissue (or in cells that display epithelial characteristics) that bear microscopic resemblance to lymphoepithelioma (nasopharyngeal carcinoma).

There is considerable variation in the classification of LELC—while it is perhaps most commonly considered a subtype of squamous cell carcinoma, it can also be classified as a form of large cell carcinoma (i.e. when occurring in the lung), and can be considered as a separate, unique entity.

In most anatomical sites, many cases are associated with the Epstein-Barr virus.

In the breast, the macroscopic, microscopic, epidemiologic, and prognostic features of LELC are very similar to "medullary carcinoma"; EBV status is one differentiator.

Serous cystadenoma may refer to:

- Ovarian serous cystadenoma, a very common benign tumour of the ovary.

- Pancreatic serous cystadenoma, also known as "serous microcystic adenoma".

Epithelial-myoepithelial carcinoma of the lung (EMECL) is a very rare histologic form of malignant epithelial neoplasm ("carcinoma") arising from lung tissue.

A Clear-cell carcinoma is a carcinoma (i.e. not a sarcoma) showing clear cells.

"A rare type of tumor, usually of the female genital tract, in which the insides of the cells look clear when viewed under a microscope. Also called clear cell adenocarcinoma and mesonephroma."

Examples :

- Clear cell renal cell carcinoma ~ clear cell kidney cancer

- Uterine clear-cell carcinoma ~ clear cell endometrial cancer

- Clear-cell ovarian carcinoma

Pathologists classify serous cystic neoplasms into two broad groups. Those that are benign, that have not spread to other organs, are designated "serous cystadenoma". Serous cystadenomas can be further sub-typed into microcystic, oligocystic (or macrocystic), solid, mixed serous-endocrine neoplasm, and VHL-associated serous cystic neoplasm. This latter classification scheme is useful because it highlights the range of appearances and the clinical associations of these neoplasms. Serous cystic neoplasms that have spread ("metastasized") to another organ are considered malignant and are designated "serous cystadenocarcinoma".

Pancreatic serous cystadenoma, also known as serous cystadenoma of the pancreas and serous microcystic adenoma, a benign tumour of pancreas. It is usually found in the head of the pancreas, and may be associated with von Hippel-Lindau syndrome.

In contrast to some of the other cyst-forming tumors of the pancreas (such as the intraductal papillary mucinous neoplasm and the mucinous cystic neoplasm), serous cystic neoplasms are almost always entirely benign. There are some exceptions; rare case reports have described isolated malignant serous cystadenocarcinomas. In addition, serous cystic neoplasms slowly grow, and if they grow large enough they can press on adjacent organs and cause symptoms.

Sarcomatoid carcinoma is a relatively uncommon form of cancer whose malignant cells have histological, cytological, or molecular properties of both epithelial tumors ("carcinoma") and mesenchymal tumors ("sarcoma").

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.

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.

Histological variants of lung cancer classified as sarcomatoid carcinoma include pleomorphic carcinoma, giant cell carcinoma, spindle cell carcinoma, carcinosarcoma, and pulmonary blastoma.