Pathology

Pathology Expert Witness

Pathology expert witnesses address cases where diagnostic error at the tissue, cellular, or molecular level led to misdiagnosis, delayed diagnosis, or inappropriate treatment. Pathologists are the physicians behind the diagnosis — their interpretation of biopsies, surgical specimens, cytology, and laboratory results drives clinical decision-making across virtually every medical specialty. Attorneys need pathology experts who can perform independent review of slides, evaluate whether the original pathologist's interpretation met the standard of care, and explain how a diagnostic error changed the patient's clinical trajectory.

When a breast biopsy showing atypical ductal hyperplasia is misinterpreted as benign fibrocystic change, and the patient is not recommended for excision or enhanced surveillance, a pathology expert can review the original slides and establish that the histologic features met diagnostic criteria for atypia, requiring different clinical management. In cases where a melanoma is under-staged on initial pathology — with Breslow thickness or mitotic rate underreported — and the patient does not receive appropriate sentinel lymph node biopsy or adjuvant therapy, the expert evaluates whether the microscopic assessment met the standard of care and whether the staging error altered the treatment plan. For surgical margin cases where a pathologist reports negative margins on a cancer resection specimen but recurrence at the surgical site suggests otherwise, the expert assesses specimen handling, margin sampling methodology, and whether inking and sectioning protocols were adequate. In laboratory error cases involving mislabeled specimens, the pathology expert evaluates the laboratory's chain-of-custody protocols and quality assurance procedures. For damages testimony, the pathology expert quantifies the impact of a missed or delayed cancer diagnosis on disease staging, treatment options, and survival probability — establishing, for example, that a melanoma diagnosed at Breslow thickness 0.8 mm carried a 95% five-year survival rate at the time the biopsy was misread, compared to a 50% survival rate at the 4.0 mm thickness when correctly diagnosed two years later. The expert also addresses the harms from false-positive diagnoses, including unnecessary mastectomy, chemotherapy toxicity, and the lasting psychological trauma of a cancer diagnosis that never existed.

A pathology expert witness evaluates diagnostic accuracy and laboratory quality across the subspecialties: surgical pathology including biopsy and resection specimen interpretation, dermatopathology, cytopathology including Pap smears and fine-needle aspirates, hematopathology, neuropathology, renal pathology, and clinical pathology including laboratory test validation and quality assurance. The expert independently reviews glass slides or high-resolution digital images, evaluates the original pathologist's diagnostic interpretation against established histologic criteria, assesses whether ancillary testing such as immunohistochemistry, flow cytometry, or molecular studies was appropriately ordered and interpreted, and determines whether the pathology report communicated findings with sufficient clarity for the treating clinician to act appropriately. For clinical pathology cases, the expert evaluates laboratory accreditation compliance, proficiency testing records, and whether critical value notification protocols were followed. The expert also assesses whether turnaround times met CAP-established benchmarks when delays are alleged to have affected patient care. Anchor matches attorneys with board-certified pathologists whose subspecialty focus aligns with the diagnostic issue — surgical pathology, cytopathology, hematopathology, or forensic pathology — to ensure the most authoritative opinion. In damages cases, the pathology expert establishes how a diagnostic error altered the patient's disease trajectory by comparing stage-specific survival curves, quantifying the treatment options lost due to delayed diagnosis, and projecting the costs of additional surveillance, salvage therapy, and palliative care that would not have been necessary with timely accurate diagnosis. For false-positive cases, the expert documents the physical harms of unnecessary surgical and medical treatment and the psychological sequelae of erroneous cancer diagnosis.