Pathology diagnosis is the cornerstone of modern medicine, analyzing samples obtained through surgical resection, endoscopic biopsy, and fine needle aspiration using microscopes or digital pathology scanners. As the definitive “gold standard” for disease diagnosis—especially in oncology—it investigates disease etiology, mechanisms, morphological changes, and functional or metabolic abnormalities to accurately determine disease nature and progression patterns.

The pathology diagnostic process typically includes sample collection, slide preparation, microscopic examination, and reporting. Based on sample type, it is categorized into histopathology (tissue-based) and cytopathology (cell-based).

• Histopathology samples are usually collected via surgery, endoscopy, or percutaneous biopsy.
• Cytopathology samples are obtained from body fluids, fine needle aspiration, or exfoliated cells.

Beyond morphological assessment, pathology integrates immunohistochemistry (IHC) and molecular pathology techniques, extending diagnosis from the tissue and cellular level to protein expression and genetic analysis.

1. Histopathology: Paraffin vs. Frozen Sections

Histopathological examination includes two primary methods:

• Paraffin Sections
  • Widely used with high resolution and long-term storability
  • Processing time: 3–5 days
  • Suitable for most diagnostic and archival purposes
• Intraoperative Frozen Sections
  • Rapid diagnosis within 30 minutes
  • Used during surgery for immediate decision-making
  • Lower section quality and higher diagnostic difficulty compared to paraffin sections

Hematoxylin and eosin (H&E) staining remains the foundational method, staining nuclei blue-purple and cytoplasmic components pink-red.

Learn more about section types

2. Cytopathology: Pap Smear vs. Liquid-Based Cytology

• Pap Smear
  Direct cell smearing; limited by cell loss and inconsistent quality.
• Liquid-Based Cytology (TCT/LBP)
  Uses membrane filtration or sedimentation to improve cell preservation and slide uniformity, now widely adopted in cervical cancer screening.

3. Immunohistochemistry (IHC): From Protein Detection to Clinical Insight

IHC localizes specific antigens in tissues using antibody-antigen binding and color development. It offers high specificity and sensitivity, playing a critical role in:

• Differentiating tumor types
• Identifying tissue origin
• Guiding targeted therapy
• Assessing prognosis

The IHC staining process involves slide preparation, dewaxing, antigen retrieval, antibody incubation, chromogenic detection, and counterstaining.

4. Molecular Pathology: Genetic Insights for Precision Medicine

Molecular pathology applies techniques such as PCR, FISH, and NGS to detect genetic alterations in tissue or cytology samples. It assists in:

• Diagnosis and subtyping
• Predicting treatment response
• Identifying therapeutic targets

Fluorescence In Situ Hybridization (FISH) uses fluorescent probes to visualize specific DNA sequences, offering high sensitivity and spatial accuracy, though it requires specialized interpretation and involves higher costs.

Supporting Technology: KFBIO Digital Pathology Scanners

KFBIO provides brightfield and fluorescence-enabled digital pathology scanners that facilitate high-resolution whole-slide imaging for H&E, IHC, and FISH applications.

• Fluorescence image stitching algorithm ensures precise slide reconstruction
• Image enhancement technology improves clarity and detail
• Quantitative analysis tools enable reproducible assessment of fluorescence signals

By integrating digital pathology solutions into diagnostic workflows, KFBIO supports pathologists in delivering accurate, efficient, and standardized diagnoses—from routine histology to advanced molecular testing.