MCC usually presents as a firm, painless, nodule (up to 2 cm diameter) or mass (>2 cm diameter). These flesh-colored, red, or blue tumors typically vary in size from 0.5 cm (less than one-quarter of an inch) to more than 5 cm (2 inches) in diameter, and usually enlarge rapidly. Although MCC's may arise almost anywhere on the body, about half originate on sun-exposed areas of the head and neck, one-third on the legs, and about one-sixth on the arms. In about 12% of cases, no obvious anatomical site of origin ("primary site") can be identified.

Merkel-cell cancers tend to invade locally, infiltrating the underlying subcutaneous fat, fascia, and muscle, and typically metastasize early in their natural history, most often to the regional lymph nodes. MCCs also spread aggressively through the blood vessels, particularly to liver, lung, brain, and bone.

Primary squamous cell thyroid carcinoma shows an aggressive biological phenotype resulting in poor prognosis for patients.

Patients typically present with a non-productive cough and weight loss.

The Clear Cell Renal Cell Carcinoma (CCRCC) is a type of renal cell carcinoma.

Ninety percent of cases of head and neck cancer (cancer of the mouth, nasal cavity, nasopharynx, throat and associated structures) are due to squamous cell carcinoma.

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

Merkel-cell carcinoma (MCC) is a rare and highly aggressive skin cancer, which, in most cases, is caused by the Merkel cell polyomavirus (MCV) discovered by scientists at the University of Pittsburgh in 2008. It is also known as cutaneous APUDoma, primary neuroendocrine carcinoma of the skin, primary small cell carcinoma of the skin, and trabecular carcinoma of the skin.

Approximately 80% of Merkel-cell carcinomas are caused by MCV. The virus is clonally integrated into the cancerous Merkel cells. In addition, the virus has a particular mutation only when found in cancer cells, but not when it is detected in healthy skin cells. Direct evidence for this oncogenetic mechanism comes from research showing that inhibition of production of MCV proteins causes MCV-infected Merkel carcinoma cells to die but has no effect on malignant Merkel cells that are not infected with this virus. MCV-uninfected tumors, which account for approximately 20% of Merkel-cell carcinomas, appear to have a separate and as-yet unknown cause. These tumors tend to have extremely high genome mutation rates, due to ultraviolet light exposure, whereas MCV-infected Merkel cell carcinomas have low rates of genome mutation. No other cancers have been confirmed so far to be caused by this virus. Because of the viral origin for this cancer, immunotherapies are a promising avenue for research to treat virus-positive Merkel-cell carcinoma.

This cancer is considered to be a form of neuroendocrine tumor. While patients with a small tumor (less than 2 cm) that has not yet metastasized to regional lymph nodes have an expected 5-year survival rate of more than 80 percent, once a lesion has metastasized regionally, the rate drops to about 50 percent. Up to half of patients that have been seemingly treated successfully (i.e. that initially appear cancer-free) subsequently suffer a recurrence of their disease. Recent reviews cite an overall 5-year survival rate of about 60% for all MCC combined.

Merkel-cell carcinoma occurs most often on the sun-exposed face, head, and neck.

Mucinous tubular and spindle cell carcinoma (MTSCC) is a rare subtype of renal cell carcinoma (RCC), that is included in the 2004 WHO classification of RCC. MTSCC is a rare neoplasm and is considered as a low-grade entity. It may be a variant of papillary RCC. This tumor occurs throughout life (age range 17–82 years) and is more frequent in females.

Large-cell carcinoma (LCC) is a heterogeneous group of undifferentiated malignant neoplasms that lack the cytologic and architectural features of small cell carcinoma and glandular or squamous differentiation. LCC is categorized as a type of NSCLC (Non-Small Cell Carcinoma) which originates from epithelial cells of the lung.

Individuals with a basal-cell carcinoma typically present with a shiny, pearly skin nodule. However, superficial basal-cell cancer can present as a red patch similar to eczema. Infiltrative or morpheaform basal-cell cancers can present as a skin thickening or scar tissue – making diagnosis difficult without using tactile sensation and a skin biopsy. It is often difficult to visually distinguish basal-cell cancer from acne scar, actinic elastosis, and recent cryodestruction inflammation.

MTSCC has a gross appearance close to papillary RCC. Microscopically, it has three histologic components: mucin, tumor cells forming tubules, and spindle cells. It is characterized by the proliferation of cuboidal and spindle cells arranged in tubular or sheet-like arrays, typically with a mucinous or myxoid background.

Giant-cell carcinoma of the lung (GCCL) is a rare histological form of large-cell lung carcinoma, a subtype of undifferentiated lung cancer, traditionally classified within the non-small-cell lung carcinomas (NSCLC).

The characteristic feature of this highly lethal malignancy is the distinctive light microscopic appearance of its extremely large cells, which are bizarre and highly pleomorphic, and which often contain more than one huge, misshapen, pleomorphic nucleus ("syncytia"), which result from cell fusion.

Although it is common in the lung cancer literature to refer to histologically mixed tumors containing significant numbers of malignant giant cells as "giant-cell carcinomas", technically a diagnosis of "giant-cell carcinoma" should be limited strictly to neoplasms containing "only" malignant giant cells (i.e. "pure" giant-cell carcinoma).

Aside from the great heterogeneity seen in lung cancers (especially those occurring among tobacco smokers), the considerable variability in diagnostic and sampling techniques used in medical practice, the high relative proportion of individuals with suspected GCCL who do not undergo complete surgical resection, and the near-universal lack of complete sectioning and pathological examination of resected tumor specimens prevent high levels of quantitative accuracy.

Clear cell papillary renal cell carcinoma, abbreviated CCPRCC and also known as clear cell tubulopapillary renal cell carcinoma, is a rare subtype of renal cell carcinoma (RCC) that has microscopic morphologic features of papillary renal cell carcinoma and clear cell renal cell carcinoma, yet is pathologically distinct based on molecular changes and immunohistochemistry.

The histopathologic classification includes:

- "Nodular basal cell carcinoma" (also known as "classic basal-cell carcinoma") most commonly occurs on the sun-exposed areas of the head and neck.

- "Cystic basal cell carcinoma" is morphologically characterized by dome-shaped, blue-gray cystic nodules.

- "Cicatricial basal cell carcinoma" (also known as "morpheaform basal cell carcinoma," and "morphoeic basal cell carcinoma") is an aggressive variant with a distinct clinical and histologic appearance.

- "Infiltrative basal cell carcinoma" is an aggressive type characterized by deep infiltration.

- "Micronodular basal cell carcinoma" is characterized by a micronodular growth pattern.

- "Superficial basal cell carcinoma" (also known as "superficial multicentric basal-cell carcinoma") occurs most commonly on the trunk and appears as an erythematous patch.

- "Pigmented basal cell carcinoma" exhibits increased melanization. About 80% of all basal-cell carcinoma in Chinese are pigmented while this subtype is uncommon in white people.

- "Rodent ulcer" (also known as a "Jacob's ulcer") is a large skin lesion of nodular basal-cell carcinoma with central necrosis. Almost all cancers can metastasize except glioma (maligancy of the central nervous system) and the rodent ulcer.

- "Fibroepithelioma of Pinkus" most commonly occurs on the lower back.

- "Polypoid basal cell carcinoma" is characterized by exophytic nodules (polyp-like structures) on the head and neck.

- "Pore-like basal cell carcinoma" resembles an enlarged pore or stellate pit.

- "Aberrant basal cell carcinoma" is characterized by the formation of basal-cell carcinoma in the absence of any apparent carcinogenic factor, occurring in odd sites such as the scrotum, vulva, perineum, nipple, and axilla.

See also:

- Nevoid basal-cell carcinoma syndrome

Clear-cell adenocarcinoma is a type of adenocarcinoma that shows clear cells.

Types include:

- Clear-cell adenocarcinoma of the vagina

- Clear-cell ovarian carcinoma

- Uterine clear-cell carcinoma

- Clear-cell adenocarcinoma of the lung (which is a type of Clear-cell carcinoma of the lung)

See also:

- Clear-cell squamous cell carcinoma of the lung

Generally, the cells have a clear cytoplasm, are surrounded by a distinct cell membrane and contain round and uniform nuclei.

Hyalinizing clear cell carcinoma, abbreviated HCCC, is a rare malignant salivary gland tumour, with a good prognosis, that is usually found on the tongue or palate.

Swelling of the lymph nodes in the neck is the initial presentation in many people, and the diagnosis of NPC is often made by lymph node biopsy. Signs and symptoms related to the primary tumor include trismus, pain, otitis media, nasal regurgitation due to paresis (loss of or impaired movement) of the soft palate, hearing loss and cranial nerve palsy (paralysis). Larger growths may produce nasal obstruction or bleeding and a "nasal twang". Metastatic spread may result in bone pain or organ dysfunction. Rarely, a paraneoplastic syndrome of osteoarthropathy (diseases of joints and bones) may occur with widespread disease.

Bowen's disease typically presents as a gradually enlarging, well-demarcated red colored plaque with an irregular border and surface crusting or scaling. Bowen's disease may occur at any age in adults, but is rare before the age of 30 years; most patients are aged over 60. Any site may be affected, although involvement of palms or soles is uncommon. Bowen's disease occurs predominantly in women (70–85% of cases). About 60–85% of patients have lesions on the lower leg, usually in previously or presently sun-exposed areas of skin.

This is a persistent, progressive, unelevated, red, scaly or crusted plaque which is due to an intraepidermal carcinoma and is potentially malignant. The lesions may occur anywhere on the skin surface, including on mucosal surfaces. Freezing, cauterization, or diathermy coagulation is often effective treatment. Pathomorphologic study of tissue sampling revealed: polymorphism of spiny epithelial cells has progressed into atypism; increased mitosis; giant and multinucleate cells; acanthosis; hyperkeratosis and parakeratosis; basal membrane and basal layer are retained.

SCC of the skin begins as a small nodule and as it enlarges the center becomes necrotic and sloughs and the nodule turns into an ulcer.

- The lesion caused by SCC is often asymptomatic

- Ulcer or reddish skin plaque that is slow growing

- Intermittent bleeding from the tumor, especially on the lip

- The clinical appearance is highly variable

- Usually the tumor presents as an ulcerated lesion with hard, raised edges

- The tumor may be in the form of a hard plaque or a papule, often with an opalescent quality, with tiny blood vessels

- The tumor can lie below the level of the surrounding skin, and eventually ulcerates and invades the underlying tissue

- The tumor commonly presents on sun-exposed areas (e.g. back of the hand, scalp, lip, and superior surface of pinna)

- On the lip, the tumor forms a small ulcer, which fails to heal and bleeds intermittently

- Evidence of chronic skin photodamage, such as multiple actinic keratoses (solar keratoses)

- The tumor grows relatively slowly

It most often arises centrally in larger bronchi, and while it often metastasizes to locoregional lymph nodes (particularly the hilar nodes) early in its course, it generally disseminates outside the thorax somewhat later than other major types of lung cancer. Large tumors may undergo central necrosis, resulting in cavitation. A squamous-cell carcinoma is often preceded for years by squamous-cell metaplasia or dysplasia in the respiratory epithelium of the bronchi, which later transforms to carcinoma in situ.

In carcinoma in situ, atypical cells may be identified by cytologic smear test of sputum, bronchoalveolar lavage or samples from endobronchial brushings. However, squamous-cell carcinoma in situ is asymptomatic and undetectable on X-ray radiographs.

Eventually, it becomes symptomatic, usually when the tumor mass begins to obstruct the lumen of a major bronchus, often producing distal atelectasis and infection. Simultaneously, the lesion invades into the surrounding pulmonary substance. On histopathology, these tumors range from well differentiated, showing keratin pearls and cell junctions, to anaplastic, with only minimal residual squamous-cell features.

Bowen's disease, also known as squamous cell carcinoma" in situ" is a neoplastic skin disease. It can be considered as an early stage or intraepidermal form of squamous cell carcinoma. It was named after John T. Bowen.

Erythroplasia of Queyrat is a particular type of Bowen's disease that can arise on the glans or prepuce in males, and, on the vulva in females, and may be induced by human papilloma virus. It is reported to occur in the corneoscleral limbus.

For several decades, primary lung cancers were consistently dichotomously classified for treatment and research purposes into small-cell lung carcinomas (SCLCs) and non-small-cell lung carcinomas (NSCLCs), based on an oversimplified approach that is now clearly outmoded. The new paradigm recognizes that lung cancers are a large and extremely heterogeneous family of malignant neoplasms, with over 50 different histological variants included in the 4th (2004) revision of the World Health Organization typing system, the most widely used lung cancer classification scheme ("WHO-2004"). These variants are increasingly appreciated as having different genetic, biological, and clinical properties, including prognoses and responses to treatment regimens, and therefore, that correct and consistent histological classification of lung cancers are necessary to validate and implement optimum management strategies.

About 1% of lung cancers are sarcomas, germ cell tumors, and hematopoietic tumors, while 99% of lung cancers are carcinoma. Carcinomas are tumors composed of transformed, abnormal cells with epithelial tissue architecture and/or molecular characteristics, and which derive from embryonic endoderm. Eight major taxa of lung carcinomas are recognized within the WHO-2004 classification:

1. Small-cell carcinoma

2. Squamous cell carcinoma

3. Adenocarcinoma

4. Large-cell carcinoma

5. Adenosquamous carcinoma

6. Sarcomatoid carcinoma

7. Carcinoid

8. Salivary gland-like carcinoma

The subclassification of GCCL among these major taxa has undergone significant changes in recent decades. Under the 2nd revision (1981) of the WHO classification, it was considered a subtype of large-cell carcinoma. In the 3rd (1999) revision, it was placed within a taxon called "Carcinomas with Pleomorphic, Sarcomatoid, or Sarcomatous Elements", along with pleomorphic carcinoma, spindle cell carcinoma, carcinosarcoma, and pulmonary blastoma, which are (arguably) related variants. While the 4th revision ("WHO-2004") retained the same grouping of lesions as the 3rd revision, the name of the major taxon was shortened to "sarcomatoid carcinomas".

The current rules for classifying lung cancers under WHO-2004, while useful and improved, remain to some extent fairly complex, ambiguous, arbitrary, and incomplete. Although it is fairly common for mixed tumors that are seen to contain malignant giant cells to be called "giant-cell carcinomas", "accurate" classification of a pulmonary tumor as a GCCL requires that the "entire tumor" consists "only" of malignant giant cells. Therefore, complete sampling of the entire tumor — obtained via a surgical resection — is absolutely necessary for a definitive diagnosis of GCCL to be made.

FA can produce repeated hemoptysis, possibly related to cavitation of the tumor.

Other presenting symptoms described have included: flu-like syndrome with cough and fever,

Synonyms for FA include well differentiated fetal adenocarcinoma, high-grade fetal adenocarcinoma, pulmonary adenocarcinoma

of fetal type, and pulmonary endodermal tumour resembling fetal lung.