L1 + 2 Pathology of the female reproductive tract Flashcards
Where do neoplasms originate from
- Cellular components of tissues
What is oestrogen secreted by
Oestrogen is secreted by the ovary stimulates maturation of squamous epithelial cells
Glycogen production during puberty by the vagina
- Glycogen is formed within mature squamous epithelial cells
- Glycogen in cells shed from the surface is a substrate for vaginal anaerobic organisms (dominated by lactobacilli)
What maintains the acidic environment in a vagina at puberty
- Lactobacilli produce lactic acid keeping vaginal pH below 4.5
Parts of the cervix
- Ectocervix
- Endocervix
- Transformation zone
Types of cells in the ectocervix
- Stratified squamous epithelium
Types of cells in the endocervix
- Single layer of tall, mucin producing columnar cells
- The endocervix is lined by columnar epithelium
Features of the endocervix
- The endocervix has a deceptively large surface area
- Columnar epithelium lines tiny blind ending channels(‘clefts’)
- These radiate out from the endocervical canal into the surrounding stroma
What is the junction between the ectocervix and endocervix called
- The junction between the two is called the ‘squamo-columnar’ junction
Describe the formation of the transformation zone
- During puberty, the cervix changes shape
- The lips of the cervix grow
- The distal end of the endocervix opens
- Endocervical mucosa becomes exposed to the acidic vaginal environment
- It is not suited to this, so undergoes an adaptive change called metaplasia
- Reserve cells in this area proliferate and mature to form squamous epithelium, this process is called squamous metaplasia
What is metaplasia
- A transformation of cell type from one kind of mature differentiated cell type to another kind of mature differentiated cell type
Features of the initial layer of metaplastic squamous epithelium that forms in the cervical transformation zone
- At first, the metaplastic squamous epithelium is thin and delicate (lots of proliferation and maturation is incomplete)
- With time, the metaplastic epithelium comes to be as strong and well formed as that on the ectocervix
What does the endometrium consist of during the proliferative phase(before ovulation)
- Tubular glands
- Specialised stroma
- Blood vessels
Mitoses in glands
What does the endometrium consist of during the secretory phase
- Cork screw glands
- Specialised stroma
- Blood vessels
Secretions in glands
Common features of neoplasia - in the female genital tract
Neoplasia -
‘New growth’ - abnormal, uncoordinated and excessive cell growth
- Persists following withdrawal of stimulus and associated
Nomenclature of neoplasms
- Different neoplasms have different behaviour
- Accurate identification and naming therefore important for treating the patient
What are neoplasms are classified according to
According to their behaviour and histogenesis
Behaviour - benign or malignant
Histogenesis - recognising the cell of origin
Features of benign neoplasms
- Remains localised and doesn’t invade surrounding tissues
- Generally grow slowly
- Good resemblance of parent tissue
What is a ‘fibroid’ leiomyoma
- A benign neoplasm of smooth muscle
- Localised
- Slow growing
- Closely resembles parent tissue
Consequences of benign neoplasms
- Pressure on adjacent tissue
- Obstruction of lumen of a hollow organ
- Hormone production
- Transformation into a malignant neoplasm
- Symptoms for the patient
How might pressure on adjacent tissue due to benign neoplasms manifest
- Bladder (frequency), rectosigmoid (constipation)
How might obstruction to lumen of a hollow organ due to a benign neoplasm manifest
- Adjacent(ureters) blocking endocervix
How might hormone production impairment due to benign neoplasm manifest
- Erythropoietin producing polycythaemia??
How might the transformation of a benign tumour into a malignant tumour manifest
- Abnormal uterine bleeding, pain
- Probably malignancy arises de novo
Behaviour of malignant neoplasms
- Invade into surrounding tissues
- Spread via lymphatics to lymph nodes and blood vessels to other sit
- Generally grow relatively quickly
- Variable resemblance to parent tissue
Malignant neoplastic tissue vs normal tissue
- Loss of differentiation
- Loss of cellular cohesion
- Enlarged irregular dark nuclei
- Increased numbers of mitoses
Consequences of malignant neoplasms
- Destruction of adjacent tissue
- Metastasis
- Blood loss from ulcerated surfaces
- Obstruction of a hollow viscera
- Production of hormones
- Weight loss and debility
- Anxiety and pain
Histogenesis of neoplasms
- Classification by cell of origin
- Determined by examining tissue under the microscope
- Resemblance to parent tissue correlates with clinical behaviour
What suffix do neoplasms have
- oma
What are carcinomas
- Malignant epithelial tumours are carcinomas
How are carcinomas named
- Carcinomas are named for the epithelial cell type which they resemble
What are carcinomas of glandular epithelium called
- adenocarcinomas
What are malignant stromal tumours called
- Sarcomas
What is dysplasia
- For some malignant neoplasms a ‘pre-malignant’ state is identified which is termed dysplasia
- Disordered growth and differentiation characterised by increased proliferation(more mitoses), atypia of cells and decreased differentiation
Features of dysplasia
- There is an accumulation of cells which look somewhat like malignant cells but do not invade the basement membrane
- Dysplastic lesions may(but don’t always) progress to invasive malignancy
- Recognising dysplastic lesions allows early treatment before invasion occurs
Examples of where dysplasia might occur
Dysplasia often occurs in sites where there is metaplasia:
- Squamous metaplasia of the cervical transformation zone
- Squamous metaplasia of the bronchial epithelium
- Glandular metaplasia of the distal oesophagus
Ratio of nuclear size to cytoplasmic volume - dyasplastic cells vs normal cells
- Normal surface cells have a small nucleus and lots of cytoplasm
- Dysplastic cells have a higher ratio of nuclear size to cytoplasmic volume, and the nuclei show the same features that we associate with malignancy
Difference between dysplasia and carcinoma
- The difference between dysplasia and carcinoma is invasion through the basement membrane
What can HPV infection cause
- Cervical intraepithelial neoplasia and cervical cancer
Features of human papillomavirus
- Human papillomoaviruses (HPVs) infect epithelium
- Confined to local site of infection without viraemia
- Over 130 HPV types, some of which infect the anogenital mucosa
- Double stranded DNA virus 7.9 Kbp
How are HPVs grouped
- HPVs may be grouped according to risk association with malignancy
Screening - HPV
Population based screening
- Cervical sample cytology
- Cervical sample HPV test
HPV treatment
- Colposcopy
- Treatment of high grade dysplasia
- Large loop excision of the transformation zone
Where is cervical cancer more common
- Cervical cancer is predominantly a disease of the developing world
Where is endometrial cancer present mostly
- Endometrial cancer is presently most common in north america and europe
Trend in prevelance of cervical cancer
- The incidence of cervical cancer has been declining(in europe)
High risk HPV
- 16 and 18
Low risk HPV
- 6 and 11
