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Germ Cell Tumors
A germ cell tumor (GCT) is a neoplasm derived from primordial germ cells. Germ-cell tumors can be cancerous or benign. Germ cell tumors typically originate from the gonads (ovary and testis), but can arise in other areas of the body. Extragonadal GCTs are thought to result from abnormal migration of germ cell precursors during development of the embryo. Classification GCTs are classified by their histology, regardless of location in the body. However, as more information about the genetics of these tumors become available, they may be classified based on specific gene mutations that characterize specific tumors. They are broadly divided in two classes: * The germinomatous or seminomatous germ-cell tumors (GGCT, SGCT) include only germinoma and its synonyms dysgerminoma and seminoma. * The nongerminomatous or nonseminomatous germ-cell tumors (NGGCT, NSGCT) include all other germ-cell tumors, pure and mixed. The two classes reflect an important clinical difference. Compared with g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micrograph
A micrograph is an image, captured photographically or digitally, taken through a microscope or similar device to show a magnify, magnified image of an object. This is opposed to a macrograph or photomacrograph, an image which is also taken on a microscope but is only slightly magnified, usually less than 10 times. Micrography is the practice or art of using microscopes to make photographs. A photographic micrograph is a photomicrograph, and one taken with an electron microscope is an electron micrograph. A micrograph contains extensive details of microstructure. A wealth of information can be obtained from a simple micrograph like behavior of the material under different conditions, the phases found in the system, failure analysis, grain size estimation, elemental analysis and so on. Micrographs are widely used in all fields of microscopy. Types Photomicrograph A light micrograph or photomicrograph is a micrograph prepared using an optical microscope, a process referred to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ICD-O
The International Classification of Diseases for Oncology (ICD-O) is a domain-specific extension of the International Statistical Classification of Diseases and Related Health Problems for tumor diseases. This classification is widely used by cancer registries. It is currently in its third revision (ICD-O-3). ICD-10 includes a list of morphology codes. They stem from ICD-O second edition (ICD-O-2) that was valid at the time of publication. Axes The classification has two axes: topography and morphology. Morphology The morphology axis addresses the microscopic structure (histology) of the tumor. This axis has particular importance because the Systematized Nomenclature of Medicine ("SNOMED") has adopted the ICD-O classification of morphology. SNOMED has been changing continuously, and several different versions of SNOMED are in use. Accordingly, mapping of ICD-O codes to SNOMED requires careful assessment of whether entities are indeed true matches. Topography The topograp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Watchful Waiting
Watchful waiting (also watch and wait or WAW) is an approach to a medical problem in which time is allowed to pass before medical intervention or therapy is used. During this time, repeated testing may be performed. Related terms include ''expectant management'', ''active surveillance'' (especially active surveillance of prostate cancer), and ''masterly inactivity''. The term ''masterly inactivity'' is also used in nonmedical contexts. A distinction can be drawn between ''watchful waiting'' and ''medical observation'', but some sources equate the terms. Usually, watchful waiting is an outpatient process and may have a duration of months or years. In contrast, medical observation is usually an inpatient process, often involving frequent or even continuous monitoring and may have a duration of hours or days. Medical uses Often watchful waiting is recommended in situations with a high likelihood of self-resolution if there is high uncertainty concerning the diagnosis, and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dermoid Cyst
A dermoid cyst is a teratoma of a cystic nature that contains an array of developmentally mature, solid tissues. It frequently consists of skin, hair follicles, and sweat glands, while other commonly found components include clumps of long hair, pockets of sebum, blood, fat, bone, nail, teeth, eyes, cartilage, and thyroid tissue. As dermoid cysts grow slowly and contain mature tissue, this type of cystic teratoma is nearly always benign. In those rare cases wherein the dermoid cyst is malignant, a squamous cell carcinoma usually develops in adults, while infants and children usually present with an endodermal sinus tumor.Freedberg, et al. (2003). ''Fitzpatrick's Dermatology in General Medicine''. (6th ed.). McGraw-Hill. . Location Due to its classification, a dermoid cyst can occur wherever a teratoma can occur. Vaginal and ovarian dermoid cysts Ovaries normally grow cyst-like structures called follicles each month. Once an egg is released from its follicle during ovulation, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Teratoma
A teratoma is a neoplasia, tumor made up of several types of biological tissue, tissue, such as hair, muscle, Human tooth, teeth, or bone. Teratomata typically form in the tailbone (where it is known as a sacrococcygeal teratoma), ovary, or testicle. Symptoms Symptoms may be minimal if the tumor is small. A testicular teratoma may present as a painless lump. Complications may include ovarian torsion, testicular torsion, or hydrops fetalis. They are a type of germ cell tumor (a tumor that begins in the cells that give rise to sperm or egg cell, eggs). They are divided into two types: mature and immature. Mature teratomas include dermoid cysts and are generally benign tumor, benign. Immature teratomas may be cancerous. Most ovarian teratomas are mature. In adults, testicular teratomas are generally cancerous. Definitive diagnosis is based on a tissue biopsy. Treatment of coccyx, testicular, and ovarian teratomas is generally by surgery. Testicular and immature ovarian terato ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Choriocarcinoma
Choriocarcinoma is a trophoblastic cancer usually located on the placenta. It is characterized by early hematogenous spread to the lungs. It belongs to the malignant end of the spectrum in gestational trophoblastic disease (GTD). It is also classified as a germ cell tumor and may arise in the testis or ovary. Signs and symptoms * increased quantitative chorionic gonadotropin (the "pregnancy hormone") levels * vaginal bleeding * shortness of breath * hemoptysis (coughing up blood) * chest pain * chest X-ray shows multiple infiltrates of various shapes in both lungs * presents in males as a testicular cancer, sometimes with skin hyperpigmentation (from excess chorionic gonadotropin cross-reacting with the alpha MSH receptor), gynecomastia, and weight loss (from excess chorionic gonadotropin cross-reacting with the LH, FSH, and TSH receptor) in males * can present with decreased thyroid-stimulating hormone (TSH) due to hyperthyroidism. Cause Choriocarcinoma of the placenta dur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endodermal Sinus Tumor
Endodermal sinus tumor (EST) is a member of the germ cell tumor group of cancers. It is the most common testicular tumor in children under three, and is also known as infantile embryonal carcinoma and yolk sac tumor. This age group has a very good prognosis. In contrast to the pure form typical of infants, adult endodermal sinus tumors are often found in combination with other kinds of germ cell tumor, particularly teratoma and embryonal carcinoma. While pure teratoma is usually benign, endodermal sinus tumor is malignant. Cause Causes for this cancer are poorly understood. Diagnosis The histology of EST is variable, but usually includes malignant endodermal cells. These cells secrete alpha-fetoprotein (AFP), which can be detected in tumor tissue, serum, cerebrospinal fluid, urine and, in the rare case of fetal EST, in amniotic fluid. When there is incongruence between biopsy and AFP test results for EST, the result indicating presence of EST dictates treatment. This is because E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha-fetoprotein
Alpha-fetoprotein (AFP, α-fetoprotein; also sometimes called alpha-1-fetoprotein, alpha-fetoglobulin, or alpha fetal protein) is a protein that in humans is encoded by the ''AFP'' gene. The ''AFP'' gene is located on the ''q'' arm of chromosome 4 (4q13.3). Maternal AFP serum level is used to screen for Down syndrome, neural tube defects, and other chromosomal abnormalities. AFP is a major plasma protein produced by the yolk sac and the fetal liver during fetal development. It is thought to be the fetal analog of serum albumin. AFP binds to copper, nickel, fatty acids and bilirubin and is found in monomeric, dimeric and trimeric forms. Structure AFP is a glycoprotein of 591 amino acids and a carbohydrate moiety. Function The function of AFP in adult humans is unknown. AFP is the most abundant plasma protein found in the human fetus. In the fetus, AFP is produced by both the liver and the yolk sac. It is believed to function as a carrier protein (similar to albumin) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Embryonal Carcinoma
Embryonal carcinoma is a relatively uncommon type of nonseminomatous germ cell tumour that occurs in the ovaries and testes. Signs and symptoms The presenting features may be a palpable testicular mass or asymmetric testicular enlargement in some cases. The tumour may present as signs and symptoms relating to the presence of widespread metastases, without any palpable lump in the testis. The clinical features associated with metastasising embryonal carcinoma may include low back pain, dyspnoea, cough, haemoptysis, haematemesis and neurologic abnormalities. Males with pure embryonal carcinoma tend to have a normal amount of the protein alpha-fetoprotein in the fluid component of their blood. The finding of elevated amounts of alpha-fetoprotein is more suggestive of a mixed germ cell tumour, with the alpha-fetoprotein being released by the yolk sac tumour component. Diagnosis The gross examination usually shows a two to three centimetre pale grey, poorly defined tumour w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seminoma
A seminoma is a germ cell tumor of the testicle or, more rarely, the mediastinum or other extra-gonadal locations. It is a Malignancy, malignant neoplasm and is one of the most treatable and curable cancers, with a survival rate above 95% if discovered in early stages. Testicular seminoma originates in the Germinal epithelium (male), germinal epithelium of the seminiferous tubules. About half of germ cell tumors of the testicles are seminomas. Treatment usually requires removal of one testicle. However, fertility is not usually affected. All other sexual functions will remain intact. Signs and symptoms The average age of diagnosis is between 35 and 50 years. This is about 5 to 10 years older than men with other germ cell tumors of the testes. In most cases, they produce masses that are readily felt on testicular self-examination; however, in up to 11 percent of cases, there may be no mass able to be felt, or there may be testicular atrophy. Testicular pain is reported in up ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dysgerminoma
A dysgerminoma is a type of germ cell tumor; it usually is malignant and usually occurs in the ovary. A tumor of the identical histology but not occurring in the ovary may be described by an alternate name: seminoma in the testis or germinoma in the central nervous system or other parts of the body. Dysgerminoma accounts for less than 1% of ovarian tumors overall. Dysgerminoma usually occurs in adolescence and early adult life; about 5% occur in pre-pubertal children. Dysgerminoma is extremely rare after age 50. Dysgerminoma occurs in both ovaries in 10% of patients and, in a further 10%, there is microscopic tumor in the other ovary. Abnormal gonads (due to gonadal dysgenesis and androgen insensitivity syndrome) have a high riskNelson Textbook of Pediatrics, 18th ed. Chapter 553. Question 11, Gynecologic Problems of Childhood of developing a dysgerminoma. Most dysgerminomas are associated with elevated serum lactic dehydrogenase (LDH), which is sometimes used as a tumor marke ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Chorionic Gonadotropin
Human chorionic gonadotropin (hCG) is a hormone for the maternal recognition of pregnancy produced by trophoblast cells that are surrounding a growing embryo (syncytiotrophoblast initially), which eventually forms the placenta after implantation. The presence of hCG is detected in some pregnancy tests (HCG pregnancy strip tests). Some cancerous tumors produce this hormone; therefore, elevated levels measured when the patient is not pregnant may lead to a cancer diagnosis and, if high enough, paraneoplastic syndromes, however, it is unknown whether this production is a contributing cause or an effect of carcinogenesis. The pituitary analog of hCG, known as luteinizing hormone (LH), is produced in the pituitary gland of males and females of all ages. Beta-hCG is initially secreted by the syncytiotrophoblast. Structure Human chorionic gonadotropin is a glycoprotein composed of 237 amino acids with a molecular mass of 36.7 kDa, approximately 14.5kDa αhCG and 22.2kDa βhCG ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
