The Infectious Clue: Linking Bacterial Infections to Underlying Malignancies

Area of Science:

• Oncology
• Infectious Diseases
• Microbiology

Background:

• Bacterial infections are increasingly recognized as potential early indicators of underlying cancers.
• This link is often overlooked in clinical practice, leading to missed diagnostic opportunities.
• Hidden tumors can create conditions favoring microbial invasion, suggesting a biological basis for this association.

Purpose of the Study:

• To review the evidence linking specific bacterial infections to increased short-term cancer risk.
• To outline pathogen-specific associations and their potential pathogenetic mechanisms.
• To propose a practical diagnostic framework for identifying "sentinel infection phenotypes".

Main Methods:

• Systematic review of large registry studies and existing literature.
• Analysis of pathogen-specific associations between infections and subsequent cancer diagnoses.
• Synthesis of evidence for the
• sentinel infection phenotype
• and proposed diagnostic pathways.

Main Results:

• Specific infections like Bacteroides, Clostridium, Fusobacterium, or pks⁺E. coli bacteremia are linked to colorectal neoplasm.
• Streptococcus gallolyticus/bovis bacteremia and cryptogenic Klebsiella pneumoniae liver abscess are associated with colorectal and pancreaticobiliary cancers.
• Non-resolving pneumonia may precede lung cancer, with short-term cancer risks ranging from 3% to over 8%.

Conclusions:

• Recognizing specific bacterial infection signatures can serve as an early warning for hidden cancers.
• This approach, termed the "sentinel infection phenotype," may significantly improve early cancer detection rates.
• Implementing a diagnostic framework based on these findings could enhance patient outcomes through timely intervention.