Choriocarcinoma Health Dictionary

One of the ANTIMETABOLITES used to treat certain forms of malignant disease. Acting to inhibit the ENZYME dihydrofolate reductase, which is essential for purine and pyrimidine synthesis, it is given orally, intravenously, intramuscularly or intrathecally. Methotrexate is used as maintenance therapy for childhood acute lymphoblastic LEUKAEMIA, while other uses include CHORIOCARCINOMA, nonHodgkin’s LYMPHOMA, and various solid tumours. Intrathecally, it is used in the prophylaxis of childhood acute lymphoblastic leukaemia, and as treatment for established meningeal cancer or lymphoma.

Side-effects include suppression of myelocytes in bone marrow, in?ammation of mucous membranes, and, rarely, PNEUMONITIS. It should be avoided whenever signi?cant renal impairment is present, while signi?cant pleural e?usion or ascites is also a contraindication. Blood counts should be carefully monitored whenever intrathecal methotrexate is given. Oral or parenteral folinic acid helps to prevent, or to speed recovery from, myelosuppression or mucositis.

Methotrexate is used in dermatology, where it may be indicated for cases of severe uncontrolled PSORIASIS unresponsive to conventional therapy; it may also be indicated for severe active RHEUMATOID ARTHRITIS. Because of its potentially severe haematological, pulmonary, gastrointestinal, and other toxicities it should be used only by specialists and appropriate renal and liver function tests carried out before and during treatment. It should be avoided in pregnancy, and conception should be avoided for at least six months after stopping, as should breast feeding. Concurrent administration of aspirin or other NONSTEROIDAL ANTI-INFLAMMATORY DRUGS (NSAIDS) reduces methotrexate excretion, increasing its toxicity, and should therefore be avoided whenever possible.... methotrexate

An uncommon noncancerous tumour that develops from placental tissue early in a pregnancy in which the embryo has failed to develop normally. The mole, which resembles a bunch of grapes, is caused by degeneration of the chorionic villi. The cause of the degeneration is unknown. In a small number of affected pregnancies, the mole develops into a choriocarcinoma.Vaginal bleeding and severe morning sickness generally occur. Ultrasound scanning reveals the tumour. Urine and blood tests detect excessive amounts of human chorionic gonadotrophin (see gonadotrophin, human chorionic), which

is produced by the tumour.

The tumour can be removed by suction, a D and C, or, less commonly, a hysterectomy.... hydatidiform mole

A pregnancy in which a tumour develops from the placental tissue and the embryo does not develop normally. A molar pregnancy may be noncancerous (a hydatidiform mole) or may invade the wall of the

uterus (an invasive mole). A molar pregnancy that becomes cancerous is called a choriocarcinoma.

If the dead embryo and placenta are not expelled from the uterus after a miscarriage, the dead tissue is called a carneous mole.... molar pregnancy

Separation of all or part of the placenta from the wall of the uterus before the baby is delivered. The exact cause is not known, but placental abruption is more common in women with long-term hypertension and in those who have had the condition in a previous pregnancy or who have had several pregnancies. Smoking and high alcohol intake may also contribute to the risk of placental abruption.

Symptoms usually occur suddenly and depend on how much of the placenta has separated from the wall of the uterus. They include slight to heavy vaginal bleeding, which can be severe haemorrhaging in complete separation; cramps in the abdomen or backache; severe, constant abdominal pain; and reduced fetal movements. If the bleeding does not stop, or if it starts again, it may be necessary to induce labour (see

A small placental abruption is usu-tal. In more severe

ergency caesarean section is often necessary to save the the life of the fetus. A blood transfusion required.

placenta praevia Implantation of the placenta in the lower part of the uterus, near or over the cervix. Placenta praevia occurs in about 1 in 200 pregnancies. It varies in severity from marginal placenta praevia, when the placenta reaches the edge of the cervical opening, to complete placental praevia, when the entire opening of the cervix is covered. Mild placenta praevia may have no adverse effect. More severe cases often cause painless vaginal bleeding in late pregnancy. If the bleeding is slight and the pregnancy still has several weeks to run, bed rest in hospital may be all that is necessary. The baby will probably be delivered by caesarean section at the 38th week. If the bleeding is heavy or if the pregnancy is near term, an immediate delivery is carried out. placenta, tumours of See choriocarcinoma; hydatidiform mole.... placental abruption

A growth arising from the tissues that develop into the placenta. The most common type of trophoblastic tumour is a hydatidiform mole. (See also choriocarcinoma.)... trophoblastic tumour

a tumour arising in *germ cells, commonly in the testis and ovary but also found at other sites. Examples are *teratomas, *seminomas, *dysgerminomas, and *choriocarcinomas. They may be benign or malignant and typically occur in children and young adults. Tumour markers, including *alpha-fetoprotein and beta *human chorionic gonadotrophin, can be used to monitor disease.... germ cell tumour

(GTD) a group of disorders spanning the conditions of complete and partial molar pregnancies (see hydatidiform mole) through to the malignant conditions of invasive mole, *choriocarcinoma, and the very rare placental site trophoblastic tumour (PSTT). If there is any evidence of persistence of GTD, most commonly defined as a persistent elevation of *human chorionic gonadotrophin, the condition is described as *gestational trophoblastic neoplasia.... gestational trophoblastic disease

Catharanthus roseus

Apocynaceae

San: Nityakalyani;

Hin: Sadabahar, Baramassi;

Mal: Ushamalari, Nityakalyani

Tel: Billaganeru;

Tam: Sudukattu mallikai; Pun: Rattanjot;

Kan: Kasikanigale, Nitya Mallige

Importance: Periwinkle or Vinca is an erect handsome herbaceous perennial plant which is a chief source of patented cancer and hypotensive drugs. It is one of the very few medicinal plants which has a long history of uses as diuretic, antidysenteric, haemorrhagic and antiseptic. It is known for use in the treatment of diabetes in Jamaica and India. The alkaloids vinblastine and vincristine present in the leaves are recognized as anticancerous drugs. Vinblastine in the form of vinblastin sulphate is available in market under the trade name “VELBE” and Vincristine sulphate as “ONCOVIN” (Eli Lilly). Vinblastine is used in combination with other anticancer agents for the treatment of lymphocytic lymphoma, Hodgkin’s disease, testicular carcinoma and choriocarcinoma. Vincristine is used in acute leukemia, lymphosarcoma and Wilm’s tumour. Its roots are a major source of the alkaloids, raubasine (ajmalicine), reserpine and serpentine used in the preparation of antifibrillic and hypertension-relieving drugs. It is useful in the treatment of choriocarcinoma and Hodgkin’s disease-a cancer affecting lymph glands, spleen and liver. Its leaves are used for curing diabetes, menorrhagia and wasp stings. Root is tonic, stomachic, hypotensive, sedative and tranquilliser (Narayana and Dimri,1990).

Distribution: The plant is a native of Madagascar and hence the name Madagascar Periwinkle. It is distributed in West Indies, Mozambique, South Vi etnam, Sri Lanka , Philippines and Australia. It is well adapted to diverse agroclimatic situations prevalent in India and is commercially cultivated in the states of Tamil Nadu, Karnataka, Gujarat, Madhya Pradesh and Assam. USA, Hungary, West Germany, Italy, Netherlands and UK are the major consumers.

Botany: Catharanthus roseus (Linn.) G.Don.

syn. Vinca rosea Linn. belongs to the family Apocynaceae. It is an erect highly branched lactiferous perennial herb growing up to a height of one metre. Leaves are oblong or ovate, opposite, short-petioled, smooth with entire margin. Flowers are borne on axils in pairs. There are three flower colour types , pink, pink-eyed and white. Calyx with 5 sepal, green, linear, subulate. Corolla tube is cylindrical with 5 petals, rose-purple or white with rose-purple spot in the centre; throat of corolla tube hairy, forming a corona-like structure. The anthers are epipetalous borne on short filaments inside the bulging distal end of corolla tube converging conically above the stigma. Two characteristic secretary systems, namely a column like nectarium on both sides of pistil and a secretory cringulam circling the papillate stigma with a presumed role in pollination - fecundation process are present. Ovary bicarpellary, basally distinct with fused common style and stigma. The dehiscent fruit consists of a pair of follicles each measuring about 25 mm in length and 2.3 mm in diameter, containing up to thirty linearly arranged seeds with a thin black tegumen. On maturity, the follicles split along the length dehiscing the seeds.

Agrotechnology: Periwinkle grows well under tropical and subtropical climate. A well distributed rainfall of 1000 mm or more is ideal. In north India the low winter temperatures adversely affect the crop growth. It can grow on any type of soil ,except those which are highly saline, alkaline or waterlogged. Light soils, rich in humus are preferable for large scale cultivation since harvesting of the roots become easy.

Catharanthus is propagated by seeds. Fresh seeds should be used since they are short-viable. Seeds can be either sown directly in the field or in a nursery and then transplanted. Seed rate is 2.5 kg/ha for direct sowing and the seeds are drilled in rows 45 cm apart or broadcasted. For transplanted crop the seed rate is 500gm/ha. Seeds are sown in nursery and transplanted at 45x 30cm spacing after 60 days when the seedlings attain a height of 15-20cm Nursery is prepared two months in advance so that transplanting coincides with the on set of monsoons. Application of FYM at the rate of 15 t/ha is recommended. An alternate approach is to grow leguminous green manure crops and incorporate the same into the soil at flowering stage. Fertilisers are recommended at 80:40:40 kg N:P2O5:K2O/ha for irrigated crop and 60:30:30 kg/ha for rainfed crop. N is applied in three equal splits at planting and at 45 and 90 days after planting. 4 or 5 irrigations will be needed to optimise yield when rainfall is restricted. Fortnightly irrigations support good crop growth when the crop is grown exclusively as an irrigated crop. Weeding is carried out before each topdressing. Alternatively, use of fluchloraline at 0.75 kg a.i. /ha pre-plant or alachlor at 1.0 kg a.i. per ha as pre-emergence to weeds provides effective control of a wide range of weeds in periwinkle crop. Detopping of plants by 2cm at 50% flowering stage improves root yield and alkaloid contents. No major pests, other than Oleander hawk moth, have been reported in this crop. Fungal diseases like twig blight (top rot or dieback) caused by Phytophthora nicotianae., Pythium debaryanum, P. butleri and P. aphanidermatum; leaf spot due to Alternaria tenuissima, A. alternata, Rhizoctonia solani and Ophiobolus catharanthicola and foot-rot and wilt by Sclerotium rolfsii and Fusarium solani have been reported. However, the damage to the crop is not very serious. Three virus diseases causing different types of mosaic symptoms and a phyllody or little leaf disease due to mycoplasma -like organisms have also been reported; the spread of which could be checked by uprooting and destroying the affected plants.

The crop allows 3-4 clippings of foliage beginning from 6 months. The flowering stage is ideal for collection of roots with high alkaloid content. The crop is cut about 7 cm above the ground and dried for stem, leaf and seed. The field is irrigated, ploughed and roots are collected. The average yields of leaf, stem and root are 3.6, 1.5and 1.5 t/ha, respectively under irrigated conditions and 2.0, 1.0 and 0.75t/ha, respectively under rainfed conditions on air dry basis. The harvested stem and roots loose 80% and 70% of their weight, respectively. The crop comes up well as an undercrop in eucalyptus plantation in north India. In north western India a two year crop sequence of periwinkle-senna-mustard or periwinkle-senna- coriander are recommended for higher net returns and productivity (Krishnan,1995).

Properties and activity: More than 100 alkaloids and related compounds have so far been isolated and characterised from the plant. The alkaloid contents in different parts show large variations as roots 0.14-1.34%, stem 0.074-0.48%, leaves 0.32-1.16%, flowers 0.005-0.84%, fruits 0.40%, seeds 0.18% and pericarp 1.14% (Krishnan et al, 1983). These alkaloids includes monomeric indole alkaloids, 2-acyl indoles, oxindole, -methylene indolines, dihydroindoles, bisindole and others. Dry leaves contain vinblastine (vincaleucoblastine or VLB) 0.00013-0.00063%, and vincristine (leurocristine or LC) 0.0000003-0.0000153% which have anticancerous activity (Virmani et al, 1978). Other alkaloids reported are vincoside, isovincoside (strictosidine), catharanthine, vindolinine, lochrovicine, vincolidine, ajmalicine (raubasine), reserpine, serpentine, leurosine, lochnerine, tetrahydroalstonine, vindoline, pericalline, perivine, periformyline, perividine, carosine, leurosivine, leurosidine and rovidine. The different alkaloids possessed anticancerous, antidiabetic, diuretic, antihypertensive, antimicrobial, antidysenteric, haemorrhagic, antifibrillic, tonic, stomachic, sedative and tranquillising activities.... periwinkle

(GTN) a group of disorders characterized by persistence of *gestational trophoblastic disease, with abnormal placental development and very high levels of *human chorionic gonadotrophin (hCG). The chorionic villi are fluid-filled with vacuolation of the placenta and destruction of the normal stroma. GTN is rare in the UK, with a calculated incidence of 1/714 live births. It may develop after a molar pregnancy (see hydatidiform mole), a nonmolar pregnancy, or a live birth. The incidence after a live birth is estimated at 1/50,000. A malignant condition may develop (see choriocarcinoma) if the abnormal tissue is not completely removed and the risk of this is monitored by the fall in hCG levels. Choriocarcinoma complicates approximately 3% of complete moles, although in 50% of cases of choriocarcinoma there is no history of immediately preceding trophoblastic disease. It may also occur following a normal pregnancy. In the UK, there is an effective registration and treatment programme. The programme has achieved impressive results, with high cure (98–100%) and low chemotherapy (5–8%) rates.... gestational trophoblastic neoplasia

(hCG) a hormone, similar to the pituitary *gonadotrophins, that is produced by the placenta during pregnancy. hCG maintains the secretion of *progesterone by the corpus luteum of the ovary, the secretion of pituitary gonadotrophins being blocked during pregnancy. Large amounts are excreted in the urine, and this is used as the basis for most *pregnancy tests. Serum hCG monitoring is used for tracking early pregnancy and detecting *ectopic pregnancies (in which the level will not double over a 48-hour period, as it does with normal pregnancies). The level of hCG in the serum is also one of the indicators used in *prenatal screening tests: levels are higher in pregnancies affected by Down’s syndrome in comparison with normal pregnancies (see also papp-a; triple test). Levels of hCG are very high in *gestational trophoblastic neoplasia. Some malignant tumours (e.g. malignant teratoma, choriocarcinoma, endodermal sinus tumour) secrete hCG, which can be used as a *tumour marker. A preparation of hCG is given by injection to treat fertility problems due to ovulation disorders and to induce *superovulation in in vitro fertilization.... human chorionic gonadotrophin