Answer Happy

16. A patient who is 29 years old, and whose personal characteristics include being a cigarette "chain-smoker”, a severe alcoholic, obese, diabetic, and a recreational drug user, experiences abdominal pain and is diagnosed with appendicitis. During appendectomy surgery, the surgeon notices a single, moderate-size, well-defined liver cancer tumor. An oncologist is brought in and, the tumor is removed. The patient goes on a waiting list and, after several months, a donor-liver is obtained from a car-wreck victim. The patient's liver is removed and the donor liver is successfully transplanted in. Analyses on the patient's old (removed) liver show no cancer, suggesting that the earlier surgery had effectively removed the cancer. Thereafter, the patient continues with the same lifestyle -smoking, drinking, drugs, etc. - that led to the original cancer. Several years later, the patient gets sick and is found to have untreatable stage 4 liver cancer, which has metastasized to bone, lung, and brain. Genetic analysis shows this new cancer has all of the same mutations as the original cancer, as well as some additional new mutations that were not present originally. Which of the following are likely? a. The new cancer derived from the original tumor. Cells had already metastasized out of the original liver prior to the surgery yet these remained quiescent until the continued lifestyle drove them to re-activate after the transplant. b. The patient's continued toxic/carcinogenic lifestyle caused many of the same mutations to arise a second time in the new liver. C. The donor liver contained an undetected cancer that had many of the same mutations as those in the recipient patient.