|
|
|
|
|
|
|
|
|
|
|||||||
 |
 |
 |
 |
||||||||
|
Treating Patients with Cancer Requires Looking Beyond the Tumorby David Galloway
When a cancer is diagnosed, it is common for all attention to be focused on the tumor, and everything else—including the patient’s other medical conditions—tends to fall by the wayside. But if the patient is cured of cancer and dies of a heart attack the following week, the treatment cannot be considered a success. “It’s important to keep comorbid conditions in mind for the sake of the entire patient and not just focus on the cancer,” said Ellen F. Manzullo, M.D., F.A.C.P., an associate professor in the Department of General Internal Medicine, Ambulatory Treatment, and Emergency Care at The University of Texas M. D. Anderson Cancer Center, “because the patient can do extremely well as far as their cancer is concerned but subsequently die of coronary artery disease or stroke.” Some comorbid conditions exist before the cancer, and others develop later on. “As survival increases with cancer, we are going to run into patients who have had the time to develop other problems that might not be related to the cancer,” said Joseph Swafford, M.D., an associate professor in the Department of Cardiology at M. D. Anderson. “And when they come back for surveillance, we end up picking up on some of those problems.” Comorbidities affect cancer treatment A patient’s other medical conditions can alter the course of cancer treatment. For example, for a patient with a single lung tumor, surgery would normally be the first treatment considered. However, if that patient has severe chronic obstructive pulmonary disease or coronary artery disease, surgery might prove more deadly than the lung cancer. As many as 25% of patients whose lung tumors would otherwise be considered resectable cannot undergo surgery because of heart or lung problems, said Ritsuko Komaki, M.D., F.A.C.R., a professor in the Department of Radiation Oncology at M. D. Anderson. “We have to treat those patients with radiation therapy, alone or with chemotherapy,” she said. At the same time, internal medicine specialists administer medications or use physical therapy to improve the patient’s lung function or cardiac function so that surgery will be an option later. Of course, there are emergency situations in which there is no choice but to take a patient to surgery. But in most other cases, internists have time to evaluate the patient before surgery and develop strategies to maximize the safety and success of surgical procedures, Dr. Manzullo said. A patient’s comorbid conditions can also interfere with chemotherapy and radiation therapy. In lung cancer, “usually, we go with concurrent treatment, chemotherapy and radiation therapy,” Dr. Komaki said. “The chemotherapy will promote the radiation effects to kill more cancer cells. But it also sensitizes the normal cells, and sensitive normal cells will be killed by concurrent chemotherapy and radiation therapy.” A patient with compromised lung function or cardiac function might not be able to tolerate that damage, so researchers are searching for the optimal sequential treatment. Other conditions affecting cancer treatment include hypertension, diabetes, kidney problems, congestive heart failure, and Alzheimer’s disease. Diabetes, for example, complicates cancer treatment by interfering with a patient’s healing processes. Concurrent chemotherapy and radiation therapy, commonly used in the treatment of many cancers, lowers a patient’s blood count, especially the neutrophils. Patients with diabetes are then left especially vulnerable to infections. Although the connection might not seem obvious, Alzheimer’s disease and other cognitive disorders can alter the treatment of lung cancer. In the case of nonmetastatic small cell lung cancer (SCLC), the usual treatment includes prophylactic brain irradiation to counteract that disease’s propensity to spread to the brain. However, prophylactic brain irradiation is contraindicated if the patient’s mental function is already compromised by Alzheimer’s disease, chronic alcoholic brain syndrome, or other mental disorders. “Sometimes, these patients have medical conditions that they’re not even aware of,” Dr. Manzullo said. “They come here for their cancer treatment, and then we discover that they have other medical conditions that need to be treated.” Identifying and treating comorbid conditions can significantly affect a patient’s overall prognosis. “Sometimes, it can be just as important as the cancer itself as far as determining how well the patient will do,” Dr. Manzullo said. Cancer and treatment affect comorbidities Other comorbid conditions are caused by cancer or its treatment. SCLC, for example, produces a hormone that can lead to Eaton-Lambert syndrome, leaving a patient with severe muscle weakness. If the SCLC is resected or otherwise successfully treated, the patient’s muscle strength will return. Sometimes, a comorbid condition caused by a cancer will appear before the malignancy is found. Dr. Komaki told of a 70-year-old woman undergoing treatment for SCLC whose cancer was discovered in an attempt to diagnose a sudden mental deterioration. “She was totally confused, and so she was taken to the emergency room, where they did an MRI [magnetic resonance imaging], and there was no cancer or any other abnormality. But her sodium level was very, very low. That was caused by small cell lung cancer, or paraneoplastic syndrome. Now, after two weeks of treatment, her sodium level is up, and she walked to the park and enjoyed the weekend. Her cancer has almost gone, and the cancer-related muscle weakness and the mental confusion have disappeared.” Some common chemotherapeutic agents—paclitaxel, doxorubicin, and trastuzumab, for example—can trigger hypertension or problems with the heart, such as arrhythmias, congestive heart failure, or bradycardia. “There are some, like 5-FU [fluorouracil] and Xeloda [capecitabine], that can cause chest pains, resulting from spasms of the arteries that go to the heart,” Dr. Swafford said. Many patients on chemotherapy become anemic, and that can trigger further cardiac complications. Studies now are investigating whether drugs such as angiotensin-converting enzyme inhibitors and beta-blockers, commonly used to treat congestive heart failure, can be used to prevent that condition in patients undergoing chemotherapy. Other agents affect the kidneys, sometimes to the point of requiring dialysis. In addition, because many patients on chemotherapy are immunocompromised, pulmonary infections are quite common. Another treatment-related problem is esophagitis, which is caused by radiation therapy to the chest. “It is very difficult to avoid normal tissue damage right around the tumor,” Dr. Komaki said. “And the esophagus is very sensitive to radiation. Esophagitis makes it very painful to swallow food, so we do everything possible to minimize that complication.” The best way to minimize toxicity from radiation therapy is to limit the volume of tissue irradiated. Advances in imaging and radiation therapy delivery such as immobilization and respiration gating over the past few years have made it possible to irradiate less normal tissue while still hitting the tumor, and the hope is that fewer radiation-related complications will be seen. Clinicians are making many efforts to limit the side effects of cancer treatment, including using more focused radiation beams and cytoprotective agents to give normal cells a fighting chance against chemotherapy and radiation therapy. One such cytoprotector is nothing new. Amifostine (WR-2721), which was synthesized at the Walter Reed Army Institute of Research during the Cold War years to protect soldiers from radioactive fallout, is activated by alkaline phosphatase, an enzyme found in the membranes of normal cells but not (or at greatly reduced levels) in the membranes of tumor cells. Clinical trials have shown that it does protect normal cells, but not tumor cells, during concurrent chemotherapy and radiation therapy. Managing comorbid conditions on an outpatient basis Most patients treated at M. D. Anderson are seen as outpatients, and while that arrangement has many benefits for patients, it affords healthcare providers fewer opportunities to assess the patient’s overall health. “They usually eat what they want and so on, so we don’t have much control,” Dr. Komaki said. “But I think they should be treated as outpatients. Cancer patients should function as normally as they can. We should not confine them in a hospital, the way they do in some other countries. When they are outpatients, their spirit is better, and they can be more active, which is very important to maintain their appetite and weight and to reduce the chances of muscle weakness, osteoporosis, deep vein thrombosis, depression, et cetera.” At least one therapy that is normally reserved for inpatients can now be given on an outpatient basis, in the right setting. “An example of that is the use of Natrecor [nesiritide] for congestive heart failure,” Dr. Swafford said. “We’ve worked out with the ATC [Ambulatory Treatment Center] that patients can go there and get their Natrecor for six to eight hours and see if that will help decrease their need for admissions to the hospital.” On the other hand, if outpatients experience side effects when they are not at the treatment center, “we have to make sure they come to the emergency room very quickly so they don’t suffer and die of complications like sepsis,” Dr. Komaki said. The key to that, she said, is making sure patients are well informed.
For more information on this topic or for questions about M. D. Anderson’s treatments, programs, or services, call askMDAnderson at (877) MDA-6789. Other articles in OncoLog, July/August 2004 issue:
 TOP
Home/Current
Issue | Previous
Issues | Articles
by Topic | Patient Education ©2008 The University of Texas M. D. Anderson Cancer Center |
||||||||
