Cancer chemotherapy can impair the brain of a patient as it can kill crucial neural cells and cause key parts of the organ to shrink, according to two studies released this week.

The new findings add to a growing body of evidence suggesting that "chemo brain" - the mental fuzziness, memory loss and cognitive impairment is a serious problem, according to the studies.

These symptoms are often reported by cancer patients but often dismissed by oncologists.

Several studies have suggested that 40 percent to 80 percent of cancer patients receiving chemotherapy suffer from chemo brain. The problem is particularly severe for breast cancer patients because the treatment induces hormonal changes typical of menopause, and these changes can also produce memory problems.

The condition has also become more common as chemotherapy has increasingly been used at an early stage of treatment rather than as a last resort.

"Those of us on the front lines have known this for a long time, but now we have some neuropathological evidence that what we are seeing involves an anatomic change," said Dr. Stewart Fleishman, director of cancer supportive services at Beth Israel Medical Center and St. Luke's-Roosevelt Hospital Center in New York.

He said the most common question he encountered from patients during his public lectures was: "My doctor doesn't believe me. How can I convince him this is real?"

The new studies should help convince physicians who are skeptical about the issue, said Fleishman.

Because chemotherapy is a crucial cancer treatment and cannot be abandoned, scientists are calling for increased research on shielding the brain from its toxic effects and developing more- selective cancer drugs.

The studies, conducted separately by U.S. and Japanese scientists, were published in the latest journal Cancer.

Source: Xinhua