Pathology Flashcards
Histology of the ectocervix and endocervix
Ectocervix: lined by stratified, non keratinizing squamous epithelium
Endocervix: lined by columnar, mucous secreting epithelium
Squamo columnar junction
Squamo-columnar junction: the point at which the squamous and columnar epithelium meet
• At birth and in childhood, the squamo columnar junction cannot be seen
• Exposed columnar epithelium = ectropion
• Columnar cells re-epithelialise into squamous epithelium as it is more resistant to the acidic vaginal environment
What is the transformation zone?
Transformation zone: portion of columnar epithelium that is replaced by squamous epithelium (this is where pre-malignant lesions and carcinomas develop)
What is chronic cervicitis?
- Squamous metaplasia at transformation zone obstructs cervical crypt opening leading to cyst formation and stromal inflammation (acute and chronic)
- Clinically the cervix appears red, inflamed and irregular with wide transformation zone
Infective cervicitis: candidiasis
- Common, caused by overgrowth of commensal organism
- Generally causes a vulvovaginitis with pruritis, bruning and white discharge
- Treated with topical/oral antifungals
- Organisms seen on cervical pap smear
Infective cervicitis: Trichomonas
- Trichomonas vaginalis infection is transmitted by sexual contact
- Patients may be asymptomatic or have yellow, frothy vaginal discharge, vulvovaginal discomfort, dysuria and dyspareunia
• Large flagellated ovoid protozoan that can be identified on Pap smear
Acute complications and other sequela of PID
Acute complications include
• Peritonitis and bacteremia
• Endocarditis, meningitis, and supparative arthritis
Other sequelae
• Infertility, tubal obstruction
• Increased risk of ectopic pregnancy
• Intestinal obstruction due to adhesions between the bowel and pelvic organs
HSV changes seen on a pap smear
Swollen nuclei with mulitnucleation, ground glass chromatin with prominent nuclear membranes, nuclear inclusions
What proportion of females chow clinical symptoms of HSV-2? and what are they?
Clinical symptoms only seen in 1/3
o Red papules vesicles painful ulcers
Human papilloma virus
- Sexually transmitted infection
- Most patients are asymptomatic
- Double stranded DNA virus
- Over 40 genotypes can infect the genital tract
- Divided into low and high oncogenic risk categories
Lesions caused by HPV
Condyloma acuminatum
Koilocytosis
How does HPV cause pre-malignant changes?
- Integration of HPV into cell DNA allows for an overexpression of E6 and E7 viral genes which encode proteins
- Both E6 and E7 enhance degredation of p53, therefore interrupting cell death pathways
- E7 binds to p21 and prevents its function as a cell cycle inhibitor
- E7 inactivates the retinoblastoma gene (Rb) blocking its proliferation-inhibitory function
Classification of low and High grade squamous intraepithelial lesions
Low : HPV infection, CIN I
High: CIN II + III
Proportion of HPV/CIN I that progress to high grade lesion
10%
Proportion of CIN II/III that progress to carcinoma
10%
Risk factors for cervical cancer
o HPV exposure – Age at first intercourse, multiple sexual partners
o Viral oncogenicity – Persistent infection with high risk HPV subtypes
o Inefficiency of immune response – Immunosuppression, HIV infection
o Other risk factors – Smoking, coexisting infections (HSV, Chlamydia), dietary deficiencies, OCP and hormonal changes
Clinical presentation of cervical cancer
¥ Most asymptomatic
¥ Abnormal pap smear
¥ Abnormal bleeding
o Post-coital, intermenstrual
¥ Pain
¥ Haematuria
¥ Weight loss
Histological subtypes of cervical cancer
Squamous cell carcinoma most common – about 80%
¥ Precursor lesion is CIN III
¥ Characterized by nests and infiltrative tongues of malignant squamous cells invading the stroma
Adenocarcinoma
¥ About 15%
¥ Precursor lesion is adenocarcinoma in situ
Adenosquamous and NET
¥ Remaining 5%
¥ More aggressive and have a worse prognosis
PAP SMEAR
¥ Cells from transformation zone obtained via spatula or brush
¥ Smeared onto slide and stained using Papanicolaou method
¥ Liquid based medium
¥ Screened by scientist
HPV vaccine
¥ Became available in 2006
¥ Designed to reduce incidence of cervical cancer caused by HPV 16 and 18 and condylomas caused by HPV 6 and 11
¥ Available in Australia Gardasil – quadrivalent Cervarix – bivalent
¥ Most effective when given to young people before they become sexually active
¥ Girls and boys aged 12–13 can receive the HPV vaccine for free under the National Immunisation Program at their school
Congenital abnormalities of the testis and epididymis
Cryptorchordism Anorchidism Polyorchidism (>2 testes) Adrenal cortical testes Splenic-gonadal fusion
What is cryptochordism
- One or both testes fail to descend into scrotum
- May be found in inguinal canal, upper scrotum or abdomen
- Increased risk of germ cell tumours (3 -5x)
- Risk of torsion and infarction
Predisposing factors for testicular torsion and infarction
- Absence of scrotal ligament
- Shortened attachment of peritoneal ligaments incomplete descent
- Atrophy
- Needs Rx within 6-8 hrs of onset to prevent loss of testis
Hydrocele
- Commonest intrascrotal swelling
- accumulation of serous fluid within tunica vaginalis of testis
- smooth, pear-shaped swelling
- tense but usually fluctuant
- transilluminable
- testis not palpable due to surrounding fluid
Types of testicular hydrocele
Congenital
• Appears first few weeks of life
• Due to patent processus vaginalis
Secondary
• may be associated with underlying lesion of testis or epididymis:
• inflammatory; mumps, gonococcal
• neoplastic
Acute Inflammatory hydrocele – accumulates rapidly, often painful
Chronic hydrocele – stretching of tunica, dragging sensation
What is varicocele
- abnormal dilatation and tortuosity of veins of pampiniform plexus in spermatic cord
- due to insufficiency of venous valves
- 90% left sided, 10% bilateral
- associated with infertility
Common causes of viral and bacterial epididymis-orchitis?
Viral epididymo-orchitis • mumps, Coxsackie B • bilateral involvement infertility Bacterial epididymo-orchitis • young – C. trachomatis, N. gonorrhea • older – E. coli from UTI • haematolymphatic seeding – Klebsiella spp., Streptococci, Staphylococci, Salmonella, Actinomyces
Neoplasms of the testis
- Germ cell tumours (GCT)
- Sex-cord stromal tumours (SCST)
- Mixed GCT-SCST
- Primary tumours not specific to testis (lymphoma, leukaemia)
- Metastatic tumours - e.g melanoma, prostate Ca
Classic and spermatocytic seminole
Classic type:
• most common GCT (approx 50% of all cases)
• mean age at diagnosis is 40 years
• may present with painless mass; 15% normal O/E
• 30% have mets at presentation but only 3% have Sx from these mets
• PLAP(placental alkaline phosphatase) and CD117 (c-kit) POS
• serum AFP normal; 10-20% have β-HCG
Spermatocytic type • 2% of GCT and occurs only in testis • average age 65 years, present with a mass • very rarely metastasise • PLAP negative • usually cured with orchidectomy
Types of NSGCT
Embryonal carcinoma Yolk sac tumour Teratoma Choriocarcinoma Mixed germ cell tumours Intratubular germ cell neoplasia, unclassified (IGCNU)
Seminoma treatment
- Stage 1 and non-bulky stage 2 radical orchidectomy and radiation to ipsilateral paraaortic and pelvic LN (some S1 Rx with rad orchid alone); 95% cure rate for S1 and 90% for S2 tumours
- bulky S2 and advanced disease orchidectomy, radiation and chemotherapy; survival rate of 80%
NSGCT treatment
- Stage 1 radical orchidectomy and retroperitoneal lymph node dissection (90-95% cure rate; 5-10% relapse) OR radical orchidectomy and surveillance (60-70% cure rate; 30-40% relapse)
- Stage 2 non-bulky orchidectomy, LND and chemo (90% cure rate)
- Stage 2 bulky orchidectomy, chemo and resection of residual masses (cure rate 70-80%)
Leydig cell tumour
- Tumour of interstitial cells
- 1 – 3% of testicular tumours
- May be assoc with androgen or oestrogen prodn
- Present in adulthood with testicular lump
Penile congenital lesions (4)
Hypospadias
epispadias
phimosis
paraphimosis
Hypospadias
- commonest congenital abnormality of male urethra
- due to failure of fusion of urethral folds over the urogenital sinus
- commonest site is a meatus on the inferior (ventral) aspect of the glans
Epispadias
- much less common
- urethra opens onto dorsum of penis, usually at the base of the shaft near the pubis
- results in urinary incontinence and infections
Commonest medical inclination for male circumcision
Phimosis - prepuce unable to be retracted
Balanitis xerotica obliterans (BXO)
- thickened white plaques and fissures on glans and prepuce
- non-retractile prepuce or discharge
- children and elderly
- treated with circumcision
- histology similar to lichen sclerosus of vulval skin
Itching followed by appearance of closely grouped vesicles surrounded by erythema
Genital herpes - HSV2 more common
Genital warts
- commonest urogenital lesion
- infection with HPV (DNA papovavirus) types 6 and 11 (cf cutaneous warts types 1, 2 and 4)
- epidermis shows papillomatous hyperplasia
- cytoplasmic vacuolation
Primary, secondary and tertiary syphilis
primary
• Secondary stage: condyloma lata, generalised lymphadenitis
• Tertiary stage: gumma, often in testis
Polycystic ovarian disease
¥ Aka Stein-Leventhal Syndrome
¥ Numerous cystically dilated follicles, assoc with;
¥ Oligomenorrhea
¥ Obesity
¥ Hirsuitism
¥ Virilism
¥ Infertility
¥ Genetic and environmental causes; severity related to insulin resistance/obesity/‘metabolic syndrome’
¥ Rx: diet, lifestyle, diabetic meds (metformin), ovulation induction, ?wedge excision/‘drilling’ of ovary
Classification of epithelial surface tumours of the ovary
¥ Serous ¥ Mucinous ¥ Endometrioid ¥ Clear cell ¥ Transitional/Brenner
- benign, borderline or malignant
Serous tumours
¥ 20-50% of ovarian tumours
¥ Ciliated, fallopian tube-like epithelium
¥ Derived from epithelial inclusion cysts, or;
¥ Implanted epithelium from the distal fallopian tube epithelium.
¥ 70% benign = ‘serous cystadenoma’
¥ 10% borderline = ‘serous borderline tumour’
¥ 20% malignant = ‘serous (cyst)adenocarinoma’
Mucinous tumours
¥ ~25% of ovarian tumours
¥ Intestinal-like (in 85%) or endocervical-like (in 15%) mucinous epithelium
¥ 80% benign = ‘mucinous cystadenoma’
¥ 10% borderline = ‘mucinous borderline tumour’
¥ 10% malignant = mucinous (cyst)adenocarcinoma
¥ Can become very large: >30 cm; >4kg
Endometrioid tumours
¥ ~20% of ovarian tumours
¥ Often arise within endometriosis
¥ Majority of endometrioid tumours are carcinomas
Stromal tumours
Neoplasms derived from ovarian stromal cells including fibroblasts, thecal cells, granulosa cells…
Classification ¥ Fibro-thecoma* ¥ Granulosa cell tumour* (adult and juvenile types) ¥ Sertoli-leydig tumours ¥ Steroid tumours NOS ¥ Sex cord tumours with annular tubules ¥ Sclerosing stromal tumours
Germ cell tumours in ovaries and most common type
¥ 30% of ovarian tumours - teratoma
Pathological findings in pre-eclampsia and eclampsia
¥ Placental infarcts
¥ Retroplacental haematomas
¥ Increased villous ischemia (syncitial knots, villous hypomaturation)
¥ Fibrinoid necrosis of maternal vessel walls
Pathogenesis of pre eclampsia and eclampsia
¥ Abnormal formation of placental blood supply placental ischaemia release of vasoconstrictors, inflammatory mediators and prothrombotic substances vasoconstriction, endothelial injury and activation of coagulation damage to kidneys, liver, brain…
Classification of human placenta
Haemochorial - placenta where the chorion comes in direct contact with maternal blood
Discoid shaped
Implantation of the blastocyst
Commences around day 5-7, post fertilisation, completed by day 12
** blastocyst penetrates the endometrium completely
Nutrition for the blastocyst
Histiotrophic nutrition from endometrial glands until wk 10 when maternal blood supply is established (haemotrophic nutrition)
Function of the chorion, amnion, allantois and yolk sac
- The Chorion (trophoblast) will become the placenta.
- The Amnion will enclose the amniotic cavity/fluid
- The Allantois becomes the umbilical cord
- The Yolk Sac provides blood cells until the baby can make its own. This will eventually dissolve away.
Main structural and functional units of the placenta
Chorionic villi
Blood supply to the embryo
The villous structure provides a tremendous absorptive surface to facilitate exchange between the maternal and fetal circulation. The maternal blood arrives from the spiral arteries and circulates through the intervillous space. Fetal blood moves in the core of the chorionic villi within the villous vessels; thus, fetal and maternal blood is never mixed in this system.
Cells lining the placental villi
syncytiocytotrophoblasts
Stages of chorionic villi development
Primary: The chorionic villi are at first small (anchoring) and non-vascular (intermediate villi) - 13–15 days (cells: trophoblast only)
Secondary: The villi increase in size and ramify, while the mesoderm grows into them (intermediate and stem villi development) - 16–21 days (cells: trophoblast and mesoderm)
Tertiary: Branches of the umbilical vessels grow into the mesoderm, and in this way the chorionic villi are vascularized (stem villi and numerous terminal villi) – from day 21 on (cells: trophoblast, mesoderm, and blood vessels)
Blood supply to the placenta
• 2 arteries
• 1 vein
The placenta returns oxygenated (oxygen-rich) blood to the fetus via a single vessel, the umbilical vein. This process is an exception to the usual pattern (arteries carry oxygenated blood, veins carry deoxygenated blood). Some oxygenated blood from the umbilical vein passes through the fetal liver, but most of it enters the fetus’ inferior vena cava through the ductus venosus
Trophoblasts and types
• The defining cell type of the placenta is the TROPHOBLAST • Trophoblasts are epithelial cells of FETAL origin which exhibit unique properties. Four main types: o Cytotrophoblasts (CTB) o Extravillous trophoblasts (interstitial EVTs) o Endovascular trophoblasts (endovascular EVTs) o Syncytiotrophoblast (STB)
What makes up amniotic fluid in early and late pregnancy
¥ In early pregnancy amniotic fluid is initially derived from maternal blood
¥ In late pregnancy, after fetal renal development, amniotic fluid is made up primarily of fetal urine and fetal lung fluid.
Substrates transferred from maternal to fatal placenta
¥ Oxygen, carbon dioxide, carbon monoxide ¥ Water, glucose, vitamins, elements ¥ Amino acids, lactate, oxalate ¥ Cholesterol and its esters ¥ Long chain fatty acids ¥ Short chain fatty acids ¥ Steroid and thyroid hormones ¥ Electrolytes (e.g. cationic metal ions) ¥ Maternal IgG (Fc) ¥ Apolipoproteins and carrier proteins
Placental transport substrates - fetal to maternal
¥ carbon dioxide, carbon monoxide
¥ waste products - urea, uric acid, bilirubin
¥ Xenobiotics and toxins
¥ Steroid conjugates / metabolites
Blood flow factors that can limit fetal oxygenation, nutrition, and metabolism are:
(1) altered maternal perfusion
(2) altered fetoplacental perfusion
(3) reduced placental permeability
(4) increased placental metabolic needs
Placental immunological aspects
¥ Trophoblasts secrete factors which promote formation of Tregs and macrophages with a unique phenotype in decidua
¥ EVTs express ‘non-classical’ MHC I (e.g. HLA-G) as they invade the endometrium to induce uNK cell tolerance
Factors effecting fetal growth
Maternal factors:
Placental factors
Fetal factors