The Role of PET-CT in Cancer Patients Aged 85 and Older: A Tool for Precision or Overutilisation.

Introduction: This study investigates the role of positron emission tomography-computed tomography in the treatment decision-making process for cancer patients aged 85 years and older.

Methods: Retrospective study including 137 patients. Patients aged ≥ 85 years with histopathological solid malignancy. Demographic characteristics and comorbidities as well as performance status (ECOG), tumour characteristics, imaging modalities and treatment choices were variables. Patients were categorised according to PET-CT use, and statistical analyses including Mann-Whitney U test, Bonferroni correction and binary logistic regression were performed to identify independent predictors of PET-CT use.

Results: The majority of patients had ECOG 2 (69%), thoracic (32%) cancer and metastatic (70%) at diagnosis, with a median age of 89 years (range: 85-99). Comorbidities were common (73%), and the most common organ dysfunctions were renal (25%) and heart failure (24%). PET-CT was performed in 47% of the patients. PET-CT was predominantly used in patients with metastatic disease, those who had received radiotherapy and those who were given best supportive care. However, patients undergoing PET-CT had significantly lower rates of curative treatment (3% vs. 18%, p = 0.0016). Binary logistic regression identified best supportive care decision as the only independent predictor of PET-CT use.

Conclusions: The findings indicated that PET-CT is commonly used for staging in patients who are ultimately managed with palliative care. Future research should address the cost-effectiveness of PET-CT, appropriate imaging indications, and its impact on cancer-related outcomes.