These terms describe tumor types and conditions related to uterine sarcomas.

• Benign – tumor that is non-cancerous. It doesn’t spread to other parts of the body and usually grows slowly. Although benign tumors can sometimes cause problems depending on their size and location, they are generally not life-threatening.

• Clinicoradiographic correlation - the process of combining information from clinical exams, patient history, and imaging studies (like MRIs or CT scans) to make a more accurate diagnosis or treatment plan.

• Fibroid – a benign (non-cancerous) tumor made of muscle and connective tissue. Fibroids are common in the uterus and can cause symptoms like heavy periods or pelvic pain but are not cancerous.

• Leiomyosarcoma – a rare and aggressive type of cancer that arises from smooth muscle cells, often in the uterus. It can grow quickly and spread to other parts of the body, making early diagnosis crucial.

• Malignant – tumor that is cancerous. Malignant tumors can grow quickly and spread (metastasize) to other parts of the body, potentially causing serious health problems.

• Neoplasm – another word for a tumor. It refers to an abnormal growth of cells, which can be benign (non-cancerous) or malignant (cancerous).

• PEComa (Perivascular Epithelioid Cell Tumor) – a rare type of tumor made up of cells that resemble both muscle and melanin-producing cells. It often occurs in soft tissues and can sometimes involve the uterus.

• Sarcoma – a type of cancer that starts in the body's connective tissues, like muscles, bones, fat, or blood vessels. Uterine sarcomas develop in the muscles or other supporting tissues of the uterus.

• STUMP (Smooth Muscle Tumor of Uncertain Malignant Potential) – a type of uterine tumor where it’s hard to tell if it’s benign or malignant. These tumors need close monitoring because they might behave like cancer or remain non-cancerous.

• Tumor – an abnormal growth of cells. Tumors can be either benign (non-cancerous) or malignant (cancerous). Tumors in the uterus can arise from different tissues, like muscle, connective tissue, or the lining of the uterus. 

These terms describe the structure and location of tumors and tissues.

• Bizarre Nuclei / Nuclear Atypia / Atypical Cells – These all refer to cells that look abnormal under the microscope. "Bizarre nuclei" are a more extreme form of "nuclear atypia," where the center of the cell (the nucleus) looks very irregular.

• Cyst – is a sac filled with fluid or other material. Cysts can form in different parts of the body, including the uterus, and are usually benign.

• Cytoplasm – gel-like substance inside a cell that surrounds the nucleus. Pathologists examine changes in the cytoplasm to help diagnose diseases, including cancer.

• Eosinophilic - describes cells or structures that take on a pinkish color when stained and viewed under a microscope. This feature can help identify certain types of tumors or tissue changes.

• Fascicles – bundles of cells arranged in a specific, organized pattern. This feature is commonly seen in tumors arising from smooth muscle, like leiomyosarcoma.

  • Fascular (Architecture) - refers to the way tumor cells are arranged in long bundles or strands, similar to muscle fibers. This pattern is common in certain types of sarcomas and helps pathologists identify specific tumor types.

• Fibrous Stroma – refers to the connective tissue framework within a tumor. In some tumors, the stroma becomes thick and fibrous, which pathologists note as part of the tumor’s structure.

  • Stromal Cells - supporting cells in connective tissue. In the uterus, stromal cells can give rise to certain types of sarcomas, like endometrial stromal sarcoma (ESS).

  • Stroma-Based – refers to tumors that arise from or predominantly involve the connective tissue framework (stroma) of an organ, such as the uterus.

• Hypercellular – means that a tissue has more cells than normal. In tumors, hypercellularity can indicate more aggressive growth since there are more cells dividing and multiplying than usual.

  • Proliferation - refers to the rapid growth and division of cells.

• Monotonous - describes cells that all look very similar to each other. While it can indicate a benign condition, in some cases, it may suggest a uniform but aggressive type of cancer.

• Myometrium – the muscle layer of the uterus. It helps the uterus contract, such as during labor or menstruation. Tumors or sarcomas in the myometrium can affect how the uterus functions.

• Non-Fascicular Areas – refer to regions in a tumor where cells are not organized into bundles or rows (fascicles). This irregular arrangement can be a feature of certain sarcomas.

• Nuclei - The nucleus is the control center of a cell, containing its DNA. Changes in the size, shape, or number of nuclei can provide important clues about whether a tumor is benign or malignant.

• Pedunculated – a tumor that has a stalk-like structure that connects it to the surrounding tissue. Imagine a mushroom with a stem—this is similar to how a pedunculated tumor is attached to nearby tissues.

• Pleomorphic (Cells) – cells that show significant variation in size, shape, and appearance. This is often a sign of malignancy and suggests the tumor may be aggressive.

• Prolapse - refers to the dropping or slipping of an organ from its normal position. In the case of the uterus, prolapse means the uterus moves down into or outside the vaginal canal, which can sometimes complicate other conditions like tumors.

• Spindle Cells – long, thin cells that resemble a spindle or stretched-out oval shape. These cells are often found in connective tissue tumors like sarcomas.

• Squamous Epithelium – refers to a type of tissue made up of flat, thin cells that line surfaces like the skin, the inside of the mouth, and certain organs. In the uterus, it can be found on the surface of the cervix.

• Subepithelial – means located just beneath the epithelial layer (the outer layer of cells that lines organs). Subepithelial tumors are found under this layer in tissues like the uterus.

• Superficial areas – refer to the outermost layers of a tissue. Pathologists examine these areas to determine how far a tumor has spread or whether the edges (margins) of a surgical sample are clear of cancer.

• Well-Circumscribed – A tumor described as well-circumscribed has a clear and defined border. This suggests that the tumor is less likely to invade surrounding tissues, though it can still be malignant.

These terms relate to how tissues and cells are studied under the microscope.

• Atypical Cells – cells that appear abnormal under a microscope. This abnormality may indicate stress, damage, or malignancy, but not all atypical cells are cancerous.

  • Nuclear Atypia - a specific type of abnormality where the nuclei (the part of the cell that holds DNA) appear irregular in size, shape, or structure. This can indicate damaged or mutated DNA and is often a sign of cancer or a pre-cancerous condition.

  • Bizarre Nuclei - a more severe form of nuclear atypia, where the nuclei are abnormally large or have highly irregular shapes. These are often seen in aggressive or high-grade tumors and help pathologists identify malignancy.

• Chromatin – is the material inside the nucleus that contains DNA and proteins. Pathologists look at how chromatin is arranged to help identify cancer. For example, clumped or uneven chromatin may suggest malignant changes.

• Cytologically – refers to the study of individual cells and their features under a microscope. When pathologists describe something cytologically, they are focusing on how the cells look, which helps diagnose diseases like cancer.

• Degenerative/Karyorrhectic Nuclei/Necrosis – These terms describe nuclei that are breaking down or deteriorating, often seen in dying cells. This can happen naturally or in tumors, areas of necrosis can indicate aggressive growth, as the tumor outgrows its blood supply, causing some cells to die.

• High Power Fields (HPF) - are the areas a pathologist sees under the highest magnification of a microscope. When examining a tumor, pathologists count things like dividing cells or abnormalities in HPFs to assess how aggressive the tumor is.

• Histologic/Histomorphologic/Morphologically – refers to how tissues and cells look under a microscope. Pathologists use histologic analysis to determine if a tumor is benign or malignant and to identify the specific type of cancer.

• Lesion - is any abnormal area of tissue. It can refer to anything from a benign spot to a malignant tumor, and pathologists use this term to describe areas they are examining for potential disease.

• Morphologically - means looking at the shape and structure of cells and tissues under a microscope. This helps in diagnosing diseases and identifying the type of tumor.

• Mitotic/rate/count/figures - refer to cells that are actively dividing. The mitotic count or rate measures how many dividing cells are seen under a microscope, usually in High Power Fields (HPF). A high mitotic rate suggests that a tumor is growing more rapidly and may be more aggressive.

• Multinucleation – occurs when a cell has more than one nucleus. This can happen in both normal and abnormal conditions, but in tumors, it often indicates cancer or other abnormal growths.

• Nuclear Contours – describe the shape of the nucleus. Smooth contours are normal, while irregular contours can suggest changes related to cancer.

• Nuclear Pleomorphism – refers to variation in the size, shape, and appearance of cell nuclei. High pleomorphism often indicates that the cells are cancerous and may suggest a more aggressive tumor.

• Oncologist/Oncology - An oncologist is a doctor who specializes in diagnosing and treating cancer. Oncology is the branch of medicine that focuses on cancer care, including surgery, chemotherapy, and radiation therapy.

• Pathologist/Pathology - A pathologist is a doctor who studies tissues and cells under a microscope to diagnose diseases like cancer. Pathology is the field of medicine focused on understanding diseases through the examination of tissues, cells, and bodily fluids.

• Prognosis – a prediction about the likely course or outcome of a disease. For example, pathologists and oncologists use information about the tumor’s type and grade to estimate a patient’s chances of recovery or recurrence

These terms relate to lab techniques that help doctors identify proteins in tissue samples.

• Immunohistochemistry (IHC) / Immunostain / Immunohistochemical Stains – A special test that uses dyes and antibodies to detect specific proteins in a tissue sample. It helps pathologists identify the type of tumor and guide treatment by detecting unique markers.

• ATRX – a gene that helps regulate DNA structure and stability. Loss of ATRX expression in a tumor, detected through special tests, is often associated with specific cancers, including certain uterine sarcomas.

• Cathepsin-K – a protein that breaks down collagen in tissues. It is often used as a marker in pathology to identify certain tumors, such as those involving bone or connective tissues.

• Desmin/Caldesmon/MyoD1 – all of these are proteins found in muscle cells. Staining for these proteins is often used to identify tumors arising from smooth muscle, such as leiomyosarcomas.

• ER/PR (Estrogen Receptor / Progesterone Receptor) – ER stands for estrogen receptor, and PR stands for progesterone receptor. These are proteins found in some tumor cells. If a tumor is ER/PR-positive, it may grow in response to these hormones, and hormone-blocking treatments might be effective.

• Fumarate Hydratase (FH) - protein involved in energy production in cells. Mutations in the FH gene can be associated with certain types of uterine sarcomas, such as leiomyosarcoma.

• HMB-45 – a special stain used in pathology to identify certain types of cells, particularly in tumors like PEComas (perivascular epithelioid cell tumors). If a tumor reacts to this stain, it helps confirm the diagnosis.

• Melan-A – a protein commonly found in cells that produce pigment (melanocytes). Pathologists use it as a marker to help identify specific types of tumors, including rare ones like PEComas.

• P53 – a protein that acts as a "guardian" of the cell, helping to prevent cancer. If the P53 gene is mutated, it can lead to abnormal P53 protein expression, which is often seen in high-grade or aggressive cancers.

• Heterogeneous/wild-type expression pattern - A heterogeneous expression pattern means that the tumor cells show mixed or variable staining for a specific protein, while a wild-type expression pattern refers to a normal pattern of staining. These patterns help pathologists determine if genetic changes are present in the tumor.

• Immunophenotypic – refers to the unique protein markers on the surface of cells that are identified using immunostains. These markers are critical in classifying tumors and guiding treatment decisions.

  • Immunoprofile – summary of the proteins or markers detected in a tumor through immunostains. The immunoprofile helps pathologists determine the type of tumor and predict its potential behavior.

These terms describe genetic changes and testing methods used in cancer diagnosis.

• FISH (Fluorescence In Situ Hybridization) - is a special test that uses fluorescent probes to detect specific genetic changes in cells. It is often used to identify chromosomal abnormalities or gene rearrangements in tumors.

• Microsatellite (status) - Microsatellites are short, repeated sections of DNA. When we talk about their status, it refers to whether these sections are stable or unstable. Microsatellite instability (MSI) can sometimes indicate a higher risk of certain cancers or predict how a tumor will respond to treatment.

• Molecular testing – refers to analyzing a tumor’s DNA, RNA, or proteins to look for specific genetic changes. This information helps confirm a diagnosis and can guide targeted therapies for uterine sarcomas.

• mTOR inhibitors – a  type of targeted therapy used to treat tumors with specific genetic changes. They work by blocking a protein (mTOR) involved in cell growth, which can slow or stop the growth of some tumors, including PEComas.

• Mutational Burden (Muts/MB) - Mutational burden refers to the total number of genetic mutations found in a tumor. These mutations, often abbreviated as "Muts," are measured as the mutational burden (MB). A high mutational burden can make certain cancers more responsive to immunotherapy, as the immune system can more easily recognize and attack the tumor. It can also indicate how aggressive the tumor might be or guide treatment decisions.

• TFE3 gene arrangements – genetic changes that occur in some rare tumors, including certain uterine sarcomas. These rearrangements can be identified through special tests like FISH and help confirm a diagnosis.

• TSC 1/2 genes – are  involved in controlling cell growth. Mutations in these genes can lead to the development of certain tumors, including PEComas. Testing for these mutations helps guide treatment decisions.