CERVIX. MLS Basic histological diagnosis MLS HIST 422 Semester 8- batch 7 L12 : Dr. Ali Eltayb.

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1 CERVIX MLS Basic histological diagnosis MLS HIST 422 Semester 8- batch 7 L12 : Dr. Ali Eltayb.

2 CERVIX Most cervical lesions are: Most are Cervicitis. cancers ( common in women worldwide).

3 CERVICITIS Extremely common and are associated with a purulent vaginal discharge. can be subclassified as infectious or noninfectious

4 CERVICITIS Much more important pathogens are: Chlamydia trachomatis. Ureaplasma urealyticum. T. vaginalis. Candida spp. Neisseria gonorrhoeae, HSV-2 (the agent of herpes genitalis). certain types of HPV all of which are often sexually transmitted.

5 CERVICITIS C. trachomatis is by far the most common of these pathogens, accounting for as many as 40% of cases of cervicitis encountered in sexually transmitted disease (STD) clinics. Although less common, herpetic infections are noteworthy.

6 MORPHOLOGY Me be acute or chronic The acute form (uncommon )is limited to women in the postpartum period and usually is caused by staphylococci or streptococci. Chronic cervicitis consists of inflammation and epithelial regeneration Eventually, the columnar epithelium undergoes squamous metaplasia

7 C\F Cervicitis commonly comes to attention on routine examination or because of leukorrhea. Culture of the discharge must be interpreted cautiously Only the identification of known pathogens is helpful.

8 NEOPLASIA OF THE CERVIX Most tumors of the cervix are of epithelial origin and are caused by oncogenic strains of human papillomavirus (HPV).

9 the cervical transformation zone The least common, representing 5% They arise from intercalated cells of collecting ducts The tumor cells stain more darkly In general, chromophobe renal cancers have a good prognosis.

10 PATHOGENESIS HPV, the causative agent of cervical neoplasia, has a tropism for the immature squamous cells of the transformation zone. Most HPV infections are transient and are eliminated a subset of infections persists, however, and some of these progress to cervical intraepithelial neoplasia (CIN), precursor lesion from which most invasive cervical carcinomas develop..

11 Cervical Intraepithelial Neoplasia (CIN) the precancerous epithelial change HPV-related carcinogenesis usually precedes the development of an overt cancer by many years. CIN usually starts as low-grade dysplasia (CIN I) and progresses to moderate (CIN II) and then severe dysplasia (CINIII) over time. the higher the grade of CIN, the greater the likelihood of progression

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13 PATHOGENESIS HPV is detectable by molecular methods in nearly all cases of CIN and cervical carcinoma. Risk factors for cervical carcinoma Early age at first intercourse Multiple sexual partners Male partner with multiple previous sexual partners Persistent infection by high-risk strains of papillomavirusand other factors including cigarette smoking and immunodeficiency

14 PATHOGENESIS Nearly all cervical carcinomas are caused by HPV infections, particularly high-risk HPV types 16, 18, 31, and 33; the HPV vaccine is effective in preventing infection due to HPV types 16 and 18. HPV expresses E6 and E7 proteins that inactivate the p53 and Rb tumor suppressors, respectively, resulting in cell proliferation and suppression of DNA damage induced apoptosis. Loss of LKB1 gene is also involved.

15 PATHOGENESIS In (CIN II and III), HPV is incorporated into the genome of the host cell. Not all HPV infections progress to CIN III or to invasive carcinoma. The time course from infection to invasive disease is usually 10 years or more. In general, the risk of progression is proportional to the degree of dysplasia.

16 Early detection of dysplastic changes is the rationale for the Papanicolaou (Pap) test The Pap smear is a highly effective screening tool for the detection of cervical dysplasia and carcinoma and has significantly reduced the incidence of cervical carcinoma.. To date, the Pap smear remains the most successful cancer screening test ever developed

17 MORPHOLOGY CIN I is characterized by dyplastic changes in the lower third of the squamous epithelium and koilocytotic change in the superficial In CIN II, dysplasia extends to the middle third of the epithelium CIN III, is marked by almost complete loss of maturation and dysplasia extending to all layers. CIN is asymptomatic and comes to clinical attention through an abnormal Pap smear result.

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19 Invasive Carcinoma of the Cervix The most common SCC IS (75%), adenocarcinomas and mixed adenosquamous carcinomas (20%) and small cell neuroendocrine carcinomas (less than 5%). All types are caused by HPV. Risk factors for progression from CIN To invasive carcinoma include cigarette smoking and human immunodeficiency virus

20 Morphology Develop in the transformation zone Produce a barrel cervix, Graded based on their degree of squamous Differentiation. Most often is seen in women who have never had a pap smear Vaginal bleeding, leukorrhea, painful coitus (dyspareunia), or dysuria

21 Invasive Carcinoma of the Cervix Treatment is surgical by hysterectomy and lymph node dissection; small microinvasive carcinomas may be treated with cone biopsy. Mortality is most strongly related to tumor stage a

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