Diagnostic pitfalls: how availability and anchoring biases lead to errors in dermatology

Area of Science:

• Dermatology
• Pathology
• Medical Diagnostics

Background:

• Spindle cell neoplasms present diagnostic challenges.
• Cognitive heuristics, including availability and anchoring bias, can influence clinical decision-making.
• Misdiagnosis in dermatology can arise from various factors, including time pressures and knowledge gaps.

Purpose of the Study:

• To explore diagnostic similarities of spindle cell neoplasms.
• To investigate cognitive biases (availability and anchoring) contributing to misdiagnosis.
• To discuss the formation of these biases in clinical settings.

Main Methods:

• A case presentation of a 58-year-old male with persistent leg nodules.
• Initial suspicion of squamous cell carcinoma (SCC) leading to shave biopsy.
• Diagnosis of Kaposi Sarcoma confirmed during Mohs Micrographic Surgery after initial misinterpretation.

Main Results:

• Initial biopsy misidentified a lesion as dermatofibrosarcoma protuberans (DFSP).
• Availability bias influenced the initial biopsy method.
• Anchoring bias potentially affected histologic interpretation and management.
• Kaposi Sarcoma diagnosis was initially overlooked despite well-controlled HIV.

Conclusions:

• Dermatology is susceptible to misdiagnosis due to cognitive heuristics.
• Mohs Surgery evaluation facilitated a de-biased assessment, correcting the diagnosis.
• Clinicians should recognize external pressures that foster reliance on heuristics to enhance diagnostic accuracy.