Not always a miracle - The case of the missing metastasis

Area of Science:

• Oncology
• Immunology

Background:

• Spontaneous regression of malignant neoplasms is rare, with renal cell carcinoma (RCC) being a notable exception.
• This study focuses on a patient with a history of RCC and a subsequent lung metastasis.

Observation:

• A lung metastasis from RCC was detected one year after nephrectomy.
• The metastasis grew over three years until a needle biopsy confirmed its nature.
• Following the biopsy and subsequent wedge resection, no neoplastic cells were found, indicating regression.

Findings:

• The case suggests that disturbance of the tumor microenvironment, potentially through biopsy instrumentation, may activate the immune system.
• This immune activation appears to have led to the spontaneous regression of the lung metastasis.

Implications:

• This case highlights the potential role of immune system activation in neoplasm regression.
• It underscores the importance of reducing tumor burden and the impact of procedures like biopsy in potentially triggering anti-tumor immune responses.