This study is a multicenter, prospective, observational study. The study included patients aged 65 and older with solid tumors requiring systemic anti-tumor therapy. All patients underwent screening using the sG8 scale before the start of treatment, followed by routine treatment based on a plan developed through clinician decision-making. The study did not intervene in any way with the patients' diagnosis and treatment, and relevant clinical data during the treatment process were recorded accurately for follow-up patients. Study data were obtained from the electronic medical record databases and hospital information systems of multiple centers, including Sichuan Cancer Hospital. Patient clinicopathological features, pathological diagnoses, clinical stages, previous treatment histories, as well as anti-tumor treatment regimens after patient enrollment, drug dosages per cycle, treatment start times, incidence and grades of adverse events (AEs), and tumor response were extracted and collected from the medical records. All data were entered, managed, quality-controlled, exported, and analyzed through a real-world data management platform (RWDMP).

Inclusion Criteria:

1. Patients aged 65 years or older.
2. Patients with confirmed malignant tumors based on definitive pathological data.
3. Patients who are assessed by clinicians to have indications for systemic anti-tumor therapy.
4. Patients with a survival time greater than 12 weeks.

Exclusion Criteria:

1. Patients who do not meet the above inclusion criteria or are considered unsuitable for this study by the investigator due to other circumstances.
2. Patients who are unwilling to cooperate in completing the sG8 scale assessment.
3. Patients who do not understand the content of this study or are unwilling to participate.

Patients with confirmed pathological evidence of malignant solid tumors, requiring systemic anti-tumor therapy, and aged 65 years or older.