Colorectal carcinoma, Study Guides, Projects, Research of Medical Sciences

Download Colorectal carcinoma and more Study Guides, Projects, Research Medical Sciences in PDF only on Docsity! Colo-rectal carcinoma Middle colic artery Transverse Marginal mesocalon (anteriae rectae) (Common Internal iliac arter Obturator artery: Median sacral artery (from abdominal aorta) Superior vestcal artery (from patent part of umbilical artery! Interior wesical artery Middle rectal artery Branch of superior rectal artery: * Incidence : Superior mesenteric artery 1st jejunal artery lejunal and ileal (intestinal) arteries Superior rectal artery Rectusigmoid arteries Bilurcation of superior rectal artery ‘internal pudendal artery in pudendal canal (Alcock) ‘inferior rectal artery, # ie [Type the document title] = More in males above 50 years & more in black race . = Rectal carcinoma may occur in young age , around 30 years . = Carcinoma of right colon is more in females * Predisposing factors : Bilharziasis of colon is not precancerous 1. Obesity & diabetes . 2. Colorectal carcinoma in first degree relatives 3. Genetic : genetic mutation in mucosa — dysplasia — adenoma — carcinoma . 4. Benign tumors of colon: as solitary villous adenoma . All types of carcinoma of colon propably commence as a benign adenoma. 5. Familial polyposis : " The risk is 100 % in untreated cases . = Carcinoma develops particularly in villous adenomas larger than 2cm. 6. Gardner’s syndrome : = It is a type of familial polyposis coli with GIT polypi , osteomas of mandible & skull and desmoid tumor of anterior abdominal wall . 7. Ulcerative colitis. 8. Chemical carcinogens. 9. Smoking & alcohol 10. Low fibres, high animal protein & fat diet. 11.Uretero-colic implantation . [Type the document title] b.UIcerative type: = The ulcer show features of malignancy, (describe it). = This is commonest in the right colon & ampula of rectum . c. Annular stricture type: = The commonest type in upper part of rectum & sigmoid colon d. Colloid type : = The wall of the colon is infiltrated by malignant tissue containing gelatinous substance . * Colo-Rectal * * Gross Picture * ITI. Microscopic picture: A- Adenocarcinoma : ¢ 95% of cases with colo-rectal carcinom . It is one of the followings types : a. Columnar cell adenocarcinoma: malignant cells are arranged in complete or incomplete irrigular acini. b. Spheroidal cell carcinoma: groups of spheroidal cells are separated by variable amount of fibrous tissue. c. Colloid or mucoid carcinoma: it is an adenocarcinoma with excess mucin in the cells, acini and tissue spaces. [Type the document title] J / Columnar cell Spheroidal cell * Microscopic Picture * B- Squamous cell carcinoma : @ 5% , usually in the lower 1/3 of the rectum . ¢ It may be spread from carcinoma of the lower 12 of anal canal or due to squmous metaplasia . IV. Staging : TNM system > 7: Primary tumour " Tis : Tumor localized to the mucosa above the basement membrane . T1 : Tumor invades the lamina propria, muscularis mucosae, or submucosa . T2 : Tumor invades the musculosa . T3 : Tumor invades the subserosa . T4 : Tumor invades serosa or adjacent structures . > N: regional lymph node metastasis = NO: No regional lymph node metastasis * N1: 1-3 regional lymph node metastasis = N2:4or more regional lymph node metastasis > M: distal metastases . = MO: No distal metastases . = M1: presence of distal metastases . [Type the document title] Spread to other organs. * Complications : I. Spread : A) Direct spread : ¢@ Intra-mural spread : Infiltration of thickness of the wall of the colon or rectum mainly circumferential than longitudinal spread beyond palpable edge of the tumor. @ Extra-mural spread :; To the surrounding structures ( small intestine , abdominal wall , greater omentum .... etc.). = In cancer rectum anterior spread in male to the urinary bladder , prostate & seminal vesicles is delayed due to presence of fascia of Denonvillier . In female , anterior spread occurs to the vagina . = In cancer rectum posterior spread to the sacrum is delayed due to presence of Waldayer’s fascia. B) Lymphatic spread : By permeation and embolization to. ¢In cancer colon: Epicolic L.Ns. (on wall of colon)> Para- colic L.Ns. (along marginal artery) Intermediate colic L.Ns. ( along colic branches of superior & inferior mesenteric arteries [Type the document title] ‘Confluence of fymph trunks fa-cistern is unusual): Virchow’s gland & positive Tourosie's sign 10 [Type the document title] * Transverse colectomy * Lt, Hemicolectomy Upper Lt. « Epicolic colic a « Para-colic L.Ns Epicolic L.Ns Paracolic L.Ns. Sigmoid arteries Sup. Rectal . L * Sigmoid Colectomy Para Rectal L.Ns Middle Rectal a. — Middle Rectal LNs. “=| 11 [Type the document title] * Lymphatic Drainag of Rectum * . i Inf. mesenteric « Para-Aortic A. & L.Ns LNs <— 0 «Common lliac A. &L.Ns+—= "haLhe Sup. Rectal A&LNS x A. &LNS Para-| | * Middle Rectal am eres A. +L.Ns *"{ —+O @_,* Superficial inguinal L.Ns C) Blood Spread : ( 2L + 2B or LBLB ) ¢ Mainly to the liver via portal circulation, rarely to lungs, bones, brain via systemic circulation. D) Trans-peritoneal Spread : @ By seeding > malignant ascites, Krukenberg’s tumour (malignant cells implanted on the ovaries > bulky tumour), nodules in the Douglas pouch known as Blumer’s shelf , omentum and parietal peritoneum. 12 [Type the document title] B) In Carcinoma of left colon & rectum : Carcinoma of left colon Carcinoma of rectum 1. Bleeding = Common " The earliest and most constant per rectum: symptom. = Uaually = In any patient above 25 years, slight presenting with bleeding per rectum, cancer rectum must be excluded , even in presence of piles. 2. Altered = The commonest = Progressive conistipation is bowel presentation common in upper rectal cancer. habits. a. Stricture type > b.Tenesums, sense of incomplete progressive defecation, with passage of blood, constipation. mucous & necrotic material — Spurious diarrhea (usually in ampula of rectum ) 3. Large Usually chronic obstruction with progressive intestinal constipation, abdominal distension, colics and borborygmi. obstruction Acute on top of chronic obstruction often follows fecal impaction — absolute constipation . 4. Abdominal It is very rare. If a mass is felt, it is usually the feces impacted swelling above the stricture 5. Abdominal Late, due to I.0, sciatica, spread to the surrounding organs Pain Ill. Examination: a) General: for jaundice, anaemia, cachexia, Virchow’s glands & distal metastases. b) Abdominal: 15 [Type the document title] 1, Abdominal Swelling : may be felt in carcinoma of right colon as hard, irregular ill-defined mass in the right iliac fossa. It is at first mobile and later on become fixed. « D.D.: appendicular mass by the long duration & absence. of toxaemia & tenderness. 2. Enlarged, hard, nodular & tender liver. (/iver metastases) 3. Malignant ascites. 4. Abdominal masses (enlarged L.Ns & peritoneal nodules). 5. P-R and P-V examination. = It may show pelvic deposits . = In cancer rectum it allows palpation of lesions that lie within 10 cm of anal verge as a hard induration. 6. Features of distal metastases: (mention ). * D.D: " Cancer right colon : mass in the right iliac fossa . " Cancer left colon & rectum : Other causes of bleeding per rectum, intestinal obstruction . * Investigations : I) Laboratory investigations: 1. Occult blood in stoo! : usually positive . 2. Blood picture : usually show microcytic hypochromic anaemia. 3. Tumor markers : CEA , not specific , to evaluate response to treatment and follow up of the patient . II) Radiological investigations : 1. Barium enema: may show @ Cancer right colon : Persistent irregular filling defect 16 [Type the document title] @ Cancer left colon : Persistent irregular stricture ( apple core appearance ) with shouldering and moderate proximal dilatation @ Show multifocal tumors . __ Irregular filling Irregular stricture ‘defect c y * Ba. Enema * 17 [Type the document title] @ Methods : = Elective surgery by laparoscopic ( best and popular nowadays ), open or robotic (usually not available) approach. Site & operation Removed structures Restoration of bowel continuity Caecum — right Terminal 10 inches of ileum , caecum , ascending colon, | End to end hemi-colectomy | hepatic flexure , right 1/3 of transverse colon, ileocolic | ileotransverse & right colic vessels from their origin with related anatstomosis peritoneum and lymph nodes . Transverse Transverse colon , hepatic & splenic flexures , End to end colon— tanansverse mesocolon , grearer omentum , middle colic | anatstomosis transverse vessels from their origin and related lymph nodes . of colon. colectomy Descending colon | Left 1/3 of transverse colon , splenic flexure , End to end — left hemi- descending colon , upper left colic vessels from anatstomosis of colon colectomy their origin with the related lymph nodes and related peritoneum . Ascending colon | right hemi-colectomy + ligation of middle End to end or Hepatic flexure | colic vessels , removal of right 2/3 of ileotransverse — extended transverse colon with the related lymph nodes | anatstomosis right hemi- & peritoneum . colectomy Splenic flexure Left hemi-colectomy + ligation of middle End to end — extended left hemi-colectomy colic vessels , removal of left 2/3 of transverse colon with the related lymph nodes & peritoneum . anatstomosis of colon Sigmoid colon > sigmoid colectomy Sigmoid colon , sigmoid mesocolon containing sigmoid vessels from their origin and related lymph nodes . End to end anatstomosis of colon > Adjuvant post-operative radiotherapy & chemotherapy: if + ve nodes or + ve margins. 20 [Type the document title] * Carcinoma of rectum : Neoadjuvant chemotherapy and radiotherapy for all cases with T3 or T4 or +ve nodes on imaging ( TRUS OR rectal MRI). Upper 2/3 of rectum — anterior resection (also called abdominal resection with sphincter preservation or Dixon’s operation) = Ligation & division of inferior mesenteric vessels below the origin of upper left colic vessels with removal of : 1. Sigmoid colon with its mesocolon . 2. Divide the rectum 2cm below the tumour with removal of upper part of rectum . 3. Related lymph nodes and related peritoneum End to end anatstomosis between the descending colon & remaining distal rectal stump using staper device introduced from the anus . Lower 1/3 of rectum — abdomio-perineal resection (Mile’s operation ) 1. Ligation and division of the inferior mesenteric vessels (below the upper left colic artery), middle and inferior rectal vessels together with the L.Ns. along them. 2. Sigmoid colon with its mesocolon . 3. Rectum in the perirectal fascia enclosing the pararectal L.Ns. 4. Anal canal with all ischiorectal fat surrounding it . Permanent terminal left iliac colostomy = The abdominal part of Mile’s operation can be done by laparoscopic approach . * Indications of Mile’s operation : it should be done if the tumor is 2 cm or less from the anorectal junction , sphincter involvement or aggressive tumor . 21 [Type the document title] * Laparoscopic colectomy * Transverse colectomy * Lt. Hemicolectomy * Rt. Hemicolectomy Upper Lt. colic a Epicolic L.Ns Epicolic « Para-colic L.Ns Paracolic L.Ns. Sigmoid arteries Sup. Rectal * Sigmoid Colectomy Para Rectal L.Ns Middle Rectal a. —— Middle Rectal L.Ns. * 22 [Type the document title] Sigmoid Colectomy * Circular stapler used in abdominal resection 25 [Type the document title] * Anterior resection nearby tissue. . Stoma a —_ w * Abdomio-perineal resection « Abdomino-Perineal Resectiow Terminal Colostomy * Upper 2/3 of Rectum * Lower 1/3 of Rectum 26 [Type the document title] B) Inoperabale cases without acute intestinal obstruction : 1-Resectable: Palliative excision and anastomosis. 2- Irresectable: " Carcinoma of right color: side to side ileo-transverse anastomosis. = Carcinoma of left colon. Permanent transverse colostomy (to avoid obstruction). 3-Palliative chemotherapy & radiotherapy. = a, * Side to Side-ileo-transverse * * Transverse Colostomy * Anastomosis II) Colorectal carcinoma with acute intestinal obstruction : " Preoperative preparation (see IO) followed by urgent laparotomy 27