A Previously Healthy 66-year-old Man Has Been Feeling Tired For 5 Months. He Goes To His Physician, Who Performs A Complete Physical Examination, Including Stool Guaiac, Which Is Positive. A Colonoscopy Is Performed, And A Large, Sessile 4.5 Cm Mass With Surface Ulceration Is Found In The Cecum. A Biopsy Of This Mass Microscopically Shows Irregular Glands With Crowded, Tall Columnar Cells Having Marked Nuclear Hyperchromatism.

Which Of The Following Statements About His Condition Is Most Accurate?

A His Relatives Have Hereditary Adenomatous Polyposis

B There Is Lack Of Apoptosis From A Faulty Bcl-2 Gene

C A P53 Mutation Is Present In The Neoplastic Cells

D He Has Hereditary Non-polyposis Colon Cancer

E He Has Inherited A Faulty Rb Gene From One Parent


answer / Explanation:

(c) Correct.

He Has An Adenocarcinoma Of The Colon. At His Age, Apc And Hnpcc Are Very Unlikely. It Takes Many Years For Sporadic Mutations To Have Occurred That Contribute To Development Of Most Malignancies.