- Week 31: Cytopathy - Cervical screening: 25-64yo women, Identify pre-cancerous changes in the uterine cervix, 3 or 5 yearly screening intervals, Sample taken vaginally, processed in cytology and assessed for cell abnormalities, identif i es precancerous states of cervical epithelial cells. - Requirements of programme: Disease can be picked up at an early stage, can be effectively treated and there is benef it to treating early. Disease has high incidence and mortality. The test is acceptable to the screened population. Long pre-invasive stage, Cost effective, Sensitive and specif i c - HPV: 100 subtypes, low risk subtypes may cause genital warts, only high risk e.g. 16,18,31 an 33 causes CIN and cervical cancer - Transient HPV infection is common, especially in women under 35 years. Women or their partners may have had HPV for many years without knowing it. There is no reliable treatment to clear the virus. Infection persists in 20-30% of women, putting them at increased risk of developing cervical cancer - Having the virus is no enough to cause cervical cancer. Other events are required, as well as the virus embedding in the genome. Additional risk factors include those that lower your immune system, such as smoking. - It takes about 10 years for the virus to cause changes to the cervix, so that's why screening is not of f ered for women between the ages of 20-25. Prolonged infection can lead to increased risk of cervical cancer. - Obtaining sample: Visualise & assess the cervix Insert the central bristles of the brush into endocervical canal deep enough to allow the shorter outer bristles to fully contact the ectocervix Using pencil pressure rotate the brush 5 times in a clockwise direction - Pap stain - Colposcope is basically a microscope which can be used to visualise the cervix - If abnormal cells are seen in the PAP smear, then presence of HPV is tested - Non-gynae cytology - Histology - Study of tissues. - Cytology - Study of cells. - Preserve cells and present them on a slide so a diagnosis can be made, Confirm/excludemalignancy,Alsoinfectionandinflammatoryconditions,Stagingof malignancy, Often specimens also sent to microbiology to conf i rm/exclude infection. - Specimins can be exfoliative or FNA - Exfoliative - Cells shed, abraded or brushed from a mucosal surface or tissue e.g urine - FNA - Fine needle aspirate. Similar to core biopsy but uses a f i ner needle. Directly sample tissue lumps, masses and lymph nodes.
- Bronchoscopy - f i bre optic or rigid tube fed into bronchi, Camera to visualise surface mucosa. Instruments can be fed through a channel to take BX (endobronchial biopsy) etc Can also sample lymph nodes of mediastinum - TBNA (transbronchial needle aspiration ) / Wang bx, EBUS - endobronchial ultrasound technique to directly sample specif i c lymph nodes. - Bronchial wash and brush, Mucoid specimens. May be blood stained, Confirm/eliminatemalignancy.Alsoassessmentofinflammatoryconditionssuchas asthma - Sputum - nebulised saline may also be used to cause exporation of sputum. Not very sensitive, but