Colon cancer is the fourth most commonly diagnosed cancer. About 70% of cases are sporadic, while 23% are genetic. It most commonly presents in the descending and sigmoid colon as a change in bowel habits with blood or mucus in the stool. Staging involves clinical exams, imaging like CT scans, and blood tests like CEA. Treatment depends on the stage, with surgery being the main treatment and chemotherapy sometimes used adjuvantly or palliatively. The 5-year survival ranges from 100% for stage 0 to 3-30% for stage 4 disease.

1. COLON CANCERDr. Tanuj Paul Bhatia

3. COLON CANCEREPIDEMIOLOGY Colon cancer has 4th highest incidence after prostate , breast & lung cancers Second leading cause for death after lung cancerMean age at diagnosis is 5th decade

4. COLON CANCERETIOLOGYSporadic colon ca accounts for 70%> Adenomas> Tobacco> Inflammatory bowel diseases> Dietary factors> Pyrolysis products – benzo (a) pyrene> Micronutrients deficiency

5. COLON CANCERGenetics colon ca 23%> Familial adenomatous polyposis – APC > Hereditary nonpolyposis colorectal cancer Lynch 1( colonic syndrome) Lynch 2 (extracolonic syndrome)> Harmartomatous polyposis syndrome> Familial colorectal cancer

6. COLON CANCER PATHOLOGYAdenocarcinoma 90-95% - Mucinous ( colloid ) adenocarcinoma - Signet ring adenocarcinomaSirrhous tumors

7. Sarcomas

8. Neuroendocrine tumors

9. MelanomasUlcerative Ca Colon

10. COLON CANCERCLINICAL FEATURESAscending colon & caecum24 % - Bleeding , anemia , melena ,abdominal pain mass , obstruction , diarrheaTransverse colon 13% - Abdominal pain , mass , obstruction

11. Clinical features Descending & Sigmoid colon 34% - Changing bowel habits / stool caliber , mucous & blood in stools ,adbominal pain mass obstruction / perforation Metastatic disease - Cachexia , wt loss , jaundice , mass , ascites ,hepatomegaly, bloomer’s shelf , virchow’s nodes

12. COLON CANCER INVESTIGATIONSClinical ExaminationDouble contrast barium enemaColonoscopy & biopsyC T scan abdomen & pelvisChest x-rayLiver function testCarcinoembryonic AntigenPET & PET-CT - Role is emerging

13. Barium studies

14. Colonoscopy

15. VIRTUAL ENDOSCOPY CT Colonography Highly sensitive & specific in colon ca detection Polyps < 5mm sensitivity 11 – 55 %Allows simultaneous staging & imaging for synchronous lesions

17. COLON CANCER STAGINGDUKES CLASSIFICATION A – Tumor restricted to but not through bowel wall. B – Penetration through the bowel wall C – Spread to local & regional nodes C1 – Local lymph nodes involved C2 - lymph nodes at point of ligation D – Distant metasatses

18. TNM STAGING AJCC-UICC T is – Carcinoma in situT1 - Tumor invades submucosaT2 - Tumor invades into muscularis propriaT3 - Tumor invades thro muscularis propriaT4 – Tumor invades local structuresN0 – No lymph nodesN1 – 1-3 Regional LNs metsN2 – 4 Or more LNs metsN3 – LNs identified along named vascular trunkM0 – No distant metsM1 – Distant metastases

19. TNMSTAGE GROUPINGSTAGE 0 – Tis,N0,M0STAGE 1 – T1,N0,MO T2,N0,M0STAGE 2A – T3,N0,M0 2B – T4,N0,M0STAGE 3A – T –T2,N1,M0 3B - T3 –T4,N1,MO 3C - ANY T,N2,M0STAGE 4 - ANY T,ANY N,M1

20. PROGNOSTIC FACTORSAdvance stageSerosal penetrationHigh tumor gradeMore than 4 LNs involvedBowel obstn or perforationCEA levels >5ng/ml

21. MANAGEMENT OF MALIGNANT COLON POLYPS1. Pedunculated malignant polyps colon - Management by complete excision or snaring2. Sessile malignant polyps < 2cms - Snaring via colonoscopy with 2mm free margins

22. PROPHYLACTIC SURGERY POLYPSFirst consider non surgical management options before surgeryEndoscopic polypectomy reduces the incidence of subsequent cancer 50 – 70 %

23. HNPCCSubtotal coloectomy / Total coloectomy with ileorectal anastomosis

24. FAPTotal proctocolectomy and IPAAVarious designs of ileal pouchs

25. MANAGEMENTSURGERYThe extent of resection is determined by location of primary ,presence / absence of invasion into adjacent structures & distant mets

26. RIGHT HEMICOLECTOMY

27. Extended right Hemicolectomy

28. LEFT HEMICOLECTOMY

29. LAPAROSCOPY VS OPEN TECHNIQUESRecent studies confirmed technically feasible ,safe, yielding an equivalent no of lymph nodes and lengths of resected bowel when compared with open colectomy.

30. MANAGEMENT OF LIVER METASTASISAppx 15 – 25 % at initial presentation Appx 25 – 50 % will develop liver mets in 3 years following primary resectionCurative hepatic resection has a survival advantage 25 – 50 % at 5 yearsIndications . Stage 1 and 2 . Less than 4 hepatic lesions none > 5 cms without evidence of extrahepatic disease . CEA level < 5ng/ml . Disease free interval atleast 2 years

31. ALTERNATIVE MODALITIES FOR UNRESECTABLE LESIONRFA -Thermal energyCryo ablation – Rapid freezingMicrowave ablationPercutaneous enthanol infiltration USG guidedAdjuvant / pallivative hepatic artery infusionsInterstitial radiotherapy

32. STAGEWISE TREATMENT

33. STAGE 0 COLON CANCERTREATMENT OPTIONSLocal excision or simple polypectomy with clear marginsColon resection for larger lesions not amenable to local excision

34. STAGE 1 COLON CANCERSurgical resection and anastomosisAdjuvant chemotherpy is not indicated other than controlled clinical trials

35. STAGE 2 COLON CANCERWide surgical resection and anastomosisAdjuvant therapy is not indicated other than controlled clinical trials

36. STAGE 3 COLON CANCERWide surgical resection and anastomosisAdjuvant chemotherapy with 5-F.U and leucovorin for 6 monthsMOSAIC TRIAL – FOLFOX 4Oxaliplatin , leucovorin , 5 FU demonstrated prolonged 3 yrs survival

37. STAGE 4 & RECURRENT COLON CANCERSurgical resection of locally recurrent cancerSurgical resection & anastomosis or Bypass of obstruction or bleeding primary in selected metastatic casesResection of liver metastases in selected pt ( 5yr cure rate for solitary/ combination mets exceeds 20%)Resection of isolated pulmonary / ovarian mets in selected ptPalliative RadiotherapyPalliative chemotherapy