My brother passed away from germ cell cancer. it started in his abdomen. do i need to get checked for cancer?

Yes: But only as everyone else is checked -- pap smears, mammograms, colon cancer checks, physical exams. Retroperitoneal germ cell cancers strike sporadically and the vast majority don't run with any of the cancer-family syndromes. Unless there's more evidence of hereditary cancer (your physician can tell), just be cancer-smart and you'll greatly improve your chances.