An abnormal growth which is excessive and uncoordinated and it refuses to stop growing even when the stimuli are absent
3 common types of tumour in the colo-rectum
Polyps
Adenomas
Adenocarcinoma
Polyp
A tumorous growth that protrude through mucosae into the lumen of the gastro intestinal tract with or without stalk
Types of polyps
Hyperplastic
Inflammatory
Lymphoid
Hamartomatous
Adenomatous
Inflammatory polyps
Inflammed mucosa pseudo polyps
Lymphoid polyps
Aggregate of intramucosal lymphocytes
Hyperplastic polyps
May have no malignant potentials, results from decreased epithelial cell turnover
Hyperplastic polyps
Age occurrence 60-70yrs
Polyps
Less than <5cm, have smooth contour, protruding into the mucosae as single or multiple, composed of well formed glands with cripts lined by epithelial cells (goblets)
Hamartomatous polyps
Collection of malformed glands and stroma
Types of hamartomatous polyps
Juvenile - composed of mucosae glands and lamina propria, larger-1 to 3cm, occurs in less than 5years
Adults - Retention polyps, lesser in size, may be in rectum, or all the segment of colon, rounded, smooth contour with stalk
Juvenile polyposis syndrome
Rare autosomal dominant, 50-100 polyps in the GIT, carry risk of adenocarcinoma, have mutation in the gene that code TGF-B
Peutz-Jeghers polyps
Single or multiple polyp are seen throughout the GIT
Peutz-Jeghers syndrome
Multiple polyps, rare autosomal dominant
Peutz-Jeghers polyps
May be pendiunculated or arborizing network, composed of glands and connective tissue and smooth muscle, have increased potential of developing ca of pancreas, breast, lung, ovary, uterus
Peutz-Jeghers syndrome
Patients may have melanotic mucosae at the face and genital and palmar regions
Polyps in GIT, oral mucosa, face genitalia, palmer area
Have increased tendency of causing intussusception, may arise from adenomatious lesions, increased risk of developing ca of pancreas, breast, lung, ovary and uterus
Cowden syndrome
Autosomal dominant, hamarmatous lesion derived from the 3 germinal layers, have increase tendency of developing Cancer of the thyroid, breast, and oral papillomas, acral keratosis and facial trichilemma, mutation in gene PTEN
Cronkhite canada
Non-hereditory disorder, nail atrophy, skin pigmentation, alopecia
Adenomas
Are intraepithelial neoplasms, pedunculated, sessile, occur within the age- groups of 40-60yrs, equal male to female ratio, may arise sporadically or genetic linkage
Adenomas
The more familial genetic predisposition, the more risk of colorectal carcinoma
Subtypes of adenomas based on epithelial cells
Tubular
Villous
Tubulovillous
Adenomas
More common are the tubular types, all arise from increased epithelial proliferation, have dyspalsia graded as low, moderate and severe (carcinoma in-situ)
Adenomas
They are precursors to colorectal carcinoma, their precursors' risk are dependent on the size, histological architecture and severity of dysplasia
Tubular adenoma
Single or multiple, stalked or sessile, approx. 2.5cm, distributed in the GIT, composed of fibromuscuar stroma, blood vessels, lined by tall columnar
Villous adenomas
Larger in size-10cm, no stalk, multiple, velvety or cauliflower or frond-like, seen in rectum, colon, lined by dysplastic epithelium
Tubulovillous adenomas
Intermediate, stalk or sessile, dysplastic cells
Symptoms of adenomas
Asymptomic, occult bleeding, symptomatic with presentation of anaemia, rectal bleeding, secretion of mucus rich with protein and potassium
Familial syndromes
Peutz-Jegher
Juvenile polyposis syn
Cowden
Familial Adenomatous polyposis(FAP)
Hereditary nonpolyposis
Familial syndromes
Uncommon, autosomal dominant disorders, importance lies on occurrence of malignant transformation