BOOKBITS
LEAD:
Ruth Rakoff, whose two sibling David is a writer for “The New Yorker” and other sibling Simon is a well-known stand-up comedian, is herself a pretty funny woman. But then she discovered a lump in her breast everything in her busy and full life changed. She calls her new book a memoir of family, food, cancer and her couch. “When My World Was Very Small” is intensely personal, without ever becoming maudlin.