The French population is aging, and the number of newly diagnosed cancers among individuals aged 75 years and older continues to increase. The development of geriatric medicine, and particularly geriatric oncology, in collaboration with surgical and medical oncology specialists, has expanded access to innovative anticancer therapies for older adults. Although these treatments have improved therapeutic options, they are associated with adverse effects that may lead to functional decline and reduced quality of life in older patients. These consequences may also adversely affect the well-being and quality of life of their informal caregivers.

The role of informal caregivers has progressively become an integral component of cancer care. It is well established that providing care to a relative with a chronic illness can negatively impact caregivers' physical and psychological health, as well as their quality of life. While older patients are increasingly monitored through specialized geriatric oncology consultations, caregivers rarely receive systematic assessment or follow-up. Understanding the factors associated with caregiver quality of life is therefore essential to improve comprehensive patient-centered care in geriatric oncology.

This prospective observational study aims to investigate the association between baseline comprehensive geriatric assessment parameters of older patients with cancer-including functional status, nutritional status, cognition, mood, physical performance, sensory impairment, and comorbidities-and the quality of life of their caregiver. Caregiver quality of life will be assessed using the validated CarGOQoL questionnaire. Patient-caregiver dyads will be followed for six months, corresponding to the usual period for evaluating treatment tolerance and effectiveness. The findings may help identify caregivers at risk of impaired quality of life and support the integration of caregiver assessment into routine geriatric oncology practice.

The French population is aging, with approximately one in ten individuals now over 75 years of age. This demographic trend is accompanied by an increasing incidence of cancer, which remains the leading cause of mortality ahead of cardiovascular diseases across all age groups. In older adults with cancer, treatment-related adverse events are more likely to result in dose reductions or treatment discontinuation than in younger populations, particularly with chemotherapy and immunotherapy.

In geriatric oncology, regular patient reassessment is essential to evaluate treatment tolerance, monitor toxicities, detect and prevent functional decline, and identify deterioration in comorbidities. According to the literature, comprehensive geriatric reassessments are generally performed at 3, 6, or 12 months after treatment initiation.

The World Health Organization (WHO) defines quality of life (QoL) as an individual's perception of their position in life within the context of the culture and value systems in which they live, and in relation to their goals, expectations, standards, and concerns. QoL is a multidimensional concept encompassing physical health, psychological status, level of independence, social relationships, personal beliefs, and interactions with the surrounding environment. It includes both objective components (e.g., functional status, symptom burden) and subjective dimensions (e.g., personal fulfillment, life satisfaction, and well-being), making it a highly individualized and dynamic outcome.

Over the past two decades, recognition of informal caregivers has progressively increased within successive French National Cancer Plans. The term ""caregiver"" was formally introduced into the 2014-2019 Cancer Plan, reflecting the growing acknowledgement of the essential role played by family members and other non-professional caregivers. An informal caregiver is defined as a person who provides regular, unpaid assistance to an older dependent individual or a person with disabilities, helping with activities of daily living, nursing care, coordination of care, administrative tasks, psychological support, supervision, social participation, and household activities.

Government policies supporting caregivers emerged relatively late in France. Until the early 2000s, caregiver support was largely considered a private family responsibility. Financial pressures on healthcare and home-care systems subsequently highlighted the need for structured caregiver support, which has since become an integral component of national cancer strategies.

Treatment-related toxicities, functional decline, and malnutrition negatively affect the quality of life of older patients with cancer and also have a substantial impact on the quality of life of their caregivers. Balancing quality of life with survival therefore represents one of the major challenges in geriatric oncology.

Although several studies have evaluated quality of life among older patients with cancer, very few have focused on the quality of life of their primary caregivers. Symptoms such as dyspnea and pain are known to impair patients' quality of life at the end of life. In caregivers, dyspnea experienced by the patient, caregiver anxiety, and depression have been associated with increased caregiver burden. Greater caregiver burden has also been correlated with increased fatigue, anxiety, depression, and poorer overall health among caregivers.

Several validated instruments are available to assess patient quality of life, including the EORTC QLQ-C30, the EORTC QLQ-ELD14 for patients aged 70 years and older, and the SF-36 questionnaire. Caregiver burden and caregiver quality of life can be assessed using validated instruments such as the Mini-Zarit Burden Interview and the CarGOQoL questionnaire, respectively. These tools allow the experiences, concerns, and difficulties of both patients and caregivers to be quantified and integrated into comprehensive supportive care.

The French National Cancer Plan (2014-2019) emphasized the importance of incorporating caregivers' perspectives into comprehensive patient management, improving caregivers' access to supportive care services, and facilitating access to respite care. Identifying caregiver needs has therefore become a priority for healthcare organizations.

Caregivers play a central role in supporting older adults living with chronic diseases such as cancer. In neurocognitive disorders, caregiver burden is already considered an essential component of comprehensive geriatric assessment of the patient-caregiver dyad. This approach promotes coordinated care involving both hospital-based teams and community healthcare services.

Consequently, it has become important in geriatric oncology to identify the factors associated with caregiver quality of life so that caregiver-related outcomes can ultimately be incorporated into the initial comprehensive geriatric assessment, similarly to cognitive impairment.

Older adults remain underrepresented in oncology research despite the growing public health importance of cancer management in this population. Informal caregivers play a critical role in supporting older patients throughout their cancer journey, and caregiver burden may also influence patients' treatment decisions when they are aware of its impact.

The study will investigate the association between baseline comprehensive geriatric assessment parameters of older patients-including functional status, nutritional status, cognitive function, physical performance, mood, sensory impairments, and comorbidities-and the quality of life of their primary caregiver, as assessed using the validated CarGOQoL questionnaire.

The planned recruitment period has been determined to allow enrollment of a sufficient number of patient-caregiver dyads to adequately address the study objective.

Participants will be followed for six months, corresponding to the usual duration required to initiate systemic anticancer treatment and assess its tolerance and effectiveness, or, in patients receiving curative treatment, the effective duration of the planned therapeutic management.

Inclusion Criteria

Patient:

• Aged 70 years or older.
• Attending a first geriatric oncology consultation.
• Histologically confirmed diagnosis of cancer.
• Accompanied by a primary informal caregiver at the consultation.

Caregiver:

- Aged 18 years or older.

Dyad:

- The patient and caregiver have been informed about the study and do not object to participation, in accordance with French regulations governing non-interventional research.

Exclusion Criteria

Patient:

• Unable to express non-opposition to participation (e.g., under legal guardianship or presenting severe neurocognitive impairment as assessed during the consultation).
• Language barrier preventing study participation when the caregiver is unable to provide adequate interpretation.
• Objection to participation.
• Not affiliated with the French national health insurance system.
• Beneficiary of State Medical Aid

Caregiver:

• Unable to understand or complete study questionnaires in French.
• Clinically significant cognitive impairment identified during the consultation.
• Objection to participation.

Participants will consist of patient-caregiver dyads, including patients aged 70 years or older with histologically confirmed cancer and their primary informal caregiver.