Cancer is among the leading causes of morbidity and mortality worldwide, profoundly affecting patients' lives at every level, and its psychological and psychiatric impacts remain a major concern. Psychiatric disorders are frequently observed in cancer patients. Nevertheless, they were also underdiagnosed, with a consequent undermining possible interventions. Still, psychiatric disorders in cancer patients are not merely secondary complications but may actively contribute to poor oncological outcomes.

The pathophysiology of cancer-related psychiatric disorders is multifactorial and is related to several neuropsychological and neurobiological factors. Specifically, the production of cytokines associated with cancer appears to play a role in the development of depression. Tumours trigger an inflammatory response that leads to the release of pro-inflammatory cytokines. These cytokines influence central nervous system function and disrupt the regulation of the HPA axis, contributing to psychological symptoms such as depression, fatigue, sleep disturbances, and appetite loss.

Moreover, psychiatric symptoms in cancer patients are often accompanied by neuropsychological alterations including deficits in memory, executive function, and attention. Compared to other individuals with psychiatric disorders, cancer patients may experience more severe cognitive impairments which can be exacerbated by cancer treatments, including surgery, chemotherapy, and radiotherapy. These treatments stimulate cytokine production by nearby non-cancerous cells and immune cells activated in response to treatment-induced cell death, thereby driving systemic inflammation.

Cancer profoundly affects not only patients but also their families, who often bear the emotional and caregiving burden. Being close to a loved one with cancer can lead to significant psychological distress, including anxiety and depression, among family members and caregivers. The ripple effects of this burden underscore the need for a holistic approach to mental health in oncology.

Given the background presented so far, identifying and managing psychiatric comorbidities in oncological patients and their families is crucial. This multifaceted interplay between cancer and psychiatric disorders necessitates a comprehensive, interdisciplinary approach to understanding, diagnosing, and treating these conditions effectively.

Cancer is among the leading causes of morbidity and mortality worldwide, profoundly affecting patients' lives at every level. While considerable advances have been made in understanding and treating the biological aspects of cancer, its psychological and psychiatric impacts remain a major concern. Psychiatric disorders, including depression, anxiety, post-traumatic stress disorder (PTSD), and adjustment disorders, are frequently observed in cancer patients. These disorders are not only common but also underdiagnosed, as their symptoms are often misinterpreted as normal emotional reactions to the illness. This misperception undermines the recognition of significant psychiatric conditions that require targeted interventions. Still, psychiatric disorders in cancer patients are not merely secondary complications but may actively contribute to poor oncological outcomes. For instance, stress and depression can directly affect tumour biology through neuroendocrine and immune mechanisms, including increased inflammatory responses and dysregulated cortisol levels, via the chronic activation of the Hypothalamic-Pituitary-Adrenal axis (HPA). Indirectly, psychiatric symptoms can impair treatment adherence and lead to lifestyle choices that increase the risk of recurrence, such as poor nutrition, lack of physical activity, or substance use.

The pathophysiology of cancer-related psychiatric disorders is multifactorial and is related to several neuropsychological and neurobiological factors. Specifically, dysregulation of biology in cancer patients might confer greater vulnerability to psychiatric disorders. The production of cytokines associated with cancer appears to play a role in the development of depression. Tumours trigger an inflammatory response that leads to the release of pro-inflammatory cytokines, including IL-6, TNF-α, CRP, and IL-1ra. These cytokines influence central nervous system function and disrupt the regulation of the HPA axis, contributing to psychological symptoms such as depression, fatigue, sleep disturbances, and appetite loss. Since tumour-related inflammation emerges early in the progression of cancer, depression and other psychological symptoms might manifest as initial indicators of the disease.

Moreover, psychiatric symptoms in cancer patients are often accompanied by neuropsychological alterations including deficits in memory, executive function, and attention. Compared to other individuals with psychiatric disorders, cancer patients may experience more severe cognitive impairments which can be exacerbated by cancer treatments, including surgery, chemotherapy, and radiotherapy. These treatments stimulate cytokine production by nearby non-cancerous cells and immune cells activated in response to treatment-induced cell death, thereby driving systemic inflammation.

Cancer profoundly affects not only patients but also their families, who often bear the emotional and caregiving burden. Being close to a loved one with cancer can lead to significant psychological distress, including anxiety and depression, among family members and caregivers. The ripple effects of this burden underscore the need for a holistic approach to mental health in oncology.

Given the background presented so far, identifying and managing psychiatric comorbidities in oncological patients is crucial. However, there are several difficulties in assessing these patients. First, there is a need to better understand the psychopathology behind cancer. Frequently, symptoms like depression and anxiety are conceived as normal reactions to cancer, whereas cancer can trigger severe syndromes, which are frequently overlooked. Second, studies related to common biological patterns linking cancer and psychiatric disorders are poorly investigated. Furthermore, there is a lack of studies that assess the effectiveness and safety of pharmacological and non-pharmacological treatments in these patients.

Family members of cancer patients experience significant emotional and psychological strain, yet their psychiatric symptoms are often overlooked. The biological underpinnings of these symptoms in caregivers, as well as effective treatments tailored to this population, are under-researched. Addressing the mental health needs of families is essential to improving overall care outcomes in oncology.

This multifaceted interplay between cancer and psychiatric disorders necessitates a comprehensive, interdisciplinary approach to understanding, diagnosing, and treating these conditions effectively.

Inclusion Criteria:

• For cases: any subject affected by cancer with a comorbid psychiatric disorder (further defined as "cases") or any first-degree relative of a subject of a "case" (i.e., i.e. a fist-degree relative of a subject affected by cancer and a psychiatric disorder). These first-degree relatives will be defined as "cases-rel".
• For controls: a) Subjects with cancer who will undergo a consultation in the Clinical and Emergency Psychiatry Unit of the Fondazione Policlinico Universitario Agostino Gemelli IRCCS but who do not show any psychiatric symptoms (further defined as "oncology-controls"); b) subjects without cancer who will undergo a psychiatric evaluation in the Clinical and Emergency Psychiatry Unit and present psychiatric symptoms (further defined as "psy-controls"); c) Subjects without cancer and with any suspected psychiatric disorder who will undergo a psychiatric evaluation in the Clinical and Emergency Psychiatry Unit and who are not diagnosed with any relevant psychiatric symptoms after the evaluation (further defined as "healthy controls"); d) First-degree relatives of "oncology-controls", "psy-controls" and "healthy controls" (further defined as "control-rel").
• Age between 18 and 75 years.
• Capability of providing written informed consent.

Exclusion Criteria:

• Severe cognitive impairment or inability to provide written informed consent.
• Severe unstable neurological disorders, such as traumatic brain injury, Alzheimer's Disease or dementia.
• Inability to perform psychiatric or neuropsychological evaluations.

Participants will be recruited in the Clinical and Emergency Psychiatry Unit of the Fondazione Policlinico Universitario Agostino Gemelli IRCCS. The Clinical and Emergency Psychiatry Unit and provides outpatient psychiatric assessments and consultations in inpatients wards and day hospitals of the aforementioned institution. Subjects will undergo a first psychiatric evaluation by a clinician of the aforementioned unit. Then, the subject will be assigned to one of the study groups (see above).