Adolescents and young adults are a neglected age group in oncology. Younger cancer patients are also rarely included in studies – accordingly, their survival rate has hardly improved in recent years. At this year’s ESMO Congress in Madrid, experts addressed the specific challenges faced by young cancer patients at a symposium.
(ee) Young adults (in international parlance “Adolescents and Young Adults”, AYA) tend to be neglected in oncology because cancers are relatively rare among them. There is not even a uniform definition of AYA, informed Prof. Sophie Fosså, Oslo University Hospital, Norway: Different age limits of 13-29, 20-39, 18-35, or 15-34 years are mentioned in the literature. The incidence of cancer in 20- to 40-year-olds is about 2%. Only 5% of these patients have a hereditary disease due to genetic alterations. Women are affected by cancer more often than men in this age group because of the incidence of breast cancer. According to the US SEER registry (covers 28% of the US population) and the NORDCAN registry (>90% of the population in Scandinavian countries), incidence has not increased in recent decades, but mortality has decreased.
The most common tumors: Breast and testicular cancer
Specific oncological and social problems occur in the AYA age group. For example, AYA have a higher mortality rate for acute lymphoblastic leukemia (ALL) than children, and there are no treatment protocols for AYA. For colorectal and breast cancer, average survival is lower than for older adults with the same cancers. In AYA, factors such as organ growth and development, sexual development, body schema, fertility, and substance abuse also play an even more important role than in older patients. Compared with children and older adults, AYA are significantly underrepresented in clinical trials.
The most common cancers in women in the AYA age group are breast cancer, malignant melanoma, cervical cancer, and thyroid cancer; in men, testicular cancer, malignant melanoma, Hodgkin’s and non-Hodgkin’s lymphomas, and brain tumors. Young women are more likely to have prognostically unfavorable forms of breast cancer. Testicular cancer in AYA is more likely to metastasize and the proportion of non-seminomas is higher than in older patients. Melanomas in AYA are more often localized to the trunk, and the diagnosis is often made very late.
The speaker called for improved national and international collaboration and improved treatment protocols for patients in this age group. This is because, on the one hand, prognostically unfavorable factors are frequently present in AYA, and on the other hand, treatment is challenging because these patients are in a particularly vulnerable and unstable phase of life.
Too old for the Children’s Hospital, too young for oncology
Dr. Valérie Laurence, Institut Curie, Paris (F), showed which psychosocial characteristics of AYA are particularly affected by cancer. For example, cancer interferes with education and starting a career, maintaining relationships with peers and sexual relationships, and developing identity and detachment from parents. Physical changes due to the disease and, at most, loss of fertility are particularly important in AYA. Often with AYA it is not even clear where they should be treated: They are too old for a children’s hospital, and in “adult hospitals” they are often alone among many old people.
Studies from the U.S. show that unlike other age groups, AYA have not improved cancer survival in recent years. The reasons for this lack of progress are unknown. One possibility is that AYA are underrepresented in therapy studies because they are too old for studies with children. For example, the outcome for tumors that typically occur in children (rhabdomyosarcoma, Ewing’s sarcoma, osteosarcoma) is significantly worse in young adults than in children.
In young women with breast cancer, fertility is such an important factor that it influences treatment decisions in about one-quarter of patients (e.g., foregoing endocrine therapy or adjuvant chemotherapy, stopping endocrine therapy early, etc.). In addition, it takes longer for young patients to be diagnosed: They go to the doctor later than older women, and doctors think less about the possible diagnosis of breast cancer in young women.
Dr. Laurence said AYA oncology itself is still in adolescence, as there is often a lack of awareness of the special needs of this age group. However, “No disease begins or ends at age 18.” Therefore, pediatricians and adult oncologists should collaborate more in the care of AYA patients to improve their survival.
Who is responsible for the follow-up?
Dr. Daniel Stark, University of Leeds, UK, spoke about the consequences faced by individuals who developed cancer at a young age (“survivors”). Over 90% of all survivors suffer at least one consequence of toxicity by age 45, and 60-80% have a disabling or life-threatening illness. Survivors are less likely to go to college, more likely to be unemployed, more likely to have mental illness, and overall poorer quality of life compared to healthy peers. The younger a patient was when the cancer was diagnosed, the higher the risk of second tumors, especially after radiotherapy.
For these patients, primary care physicians are not necessarily the best point of contact for follow-up because primary care physicians are not familiar enough with specific problems after tumor therapies, such as hearing disorders, valvular defects, or dyslipidemias. But oncologists often can’t do a good follow-up either because they focus primarily on the cancer. The speaker called for increased protocols for long-term monitoring of survivors.
More information:
www.tyac.org.uk
(Teenagers and young adults with cancer)
www.encca.eu
(European Network for Cancer Research in Children and Adolescents)
Source: European Society for Medical Oncology (ESMO) Congress, September 26-30, 2014, Madrid.
InFo ONCOLOGY & HEMATOLOGY 2014; 2(9): 30-32.
