Misdiagnosis of pancreatic cancer
Presentation
The patient, a 36-year-old woman, had a 10-year history of a pancreatic cyst. She had two fine needle aspiration (FNA) biopsies in the previous year. The first FNA was reported as “no malignant cells identified.” The second FNA of the cyst — done three months later — was reported as “these findings suggest the possibility of a pseudocyst; however, malignancy cannot be totally excluded.”
A month after the second FNA, it was noted that cyst continued to grow, now at 7.5 cm. General Surgeon A recommended surgery to remove the pancreatic pseudocyst and a left ovarian mass. After obtaining informed consent, the patient was taken to surgery for a distal pancreatectomy with splenectomy and left oophorectomy. Multiple surgical specimens were sent to Pathologist A, the defendant in this case.
Four days after surgery, the pathology finding on the ovary was cystic follicles. The pathology finding on the spleen was congesting and capsular adhesions containing foreign body giant cells and chronic inflammation. The pancreatic pseudocyst was reported as having histiocytic and chronic inflammatory infiltrates and fibrosis; it was reported negative for malignancy.
Almost two years later, the patient returned to General Surgeon A complaining of symptoms consistent with cholelithiasis. A cholecystectomy was scheduled. Upon entering the abdomen, the surgeon encountered “multiple metastatic deposits on the peritoneum, some on the liver surface, in the pelvis and primarily on the right side of the abdominal cavity.” Multiple biopsies were obtained before removing the gallbladder. Pathologist B reported the specimens were poorly differentiated carcinoma. Subsequently, a medical oncologist diagnosed pancreatic cancer with abdominal carcinomatosis.
Pathologists at an oncology center reviewed the previous pathology slides — that were initially interpreted by Pathologist A — and reported that they showed “undifferentiated carcinoma with osteoclast-like giant cells, arising in a mucinous cystic tumor with high grade dysplasia.”
The patient was referred to an oncology center for treatment, but she died 14 months after being diagnosed.
Allegations
The plaintiffs alleged that Pathologist A was negligent in misinterpreting pathology tissue slides made from the pancreas following a partial pancreatectomy.
Legal implications
There was no indication in the medical record or during the investigation of this claim to indicate that Pathologist A deviated from her normal routine when handling, processing, and reviewing the patient’s specimen. However, when Pathologist A re-examined the slides, she stated that she believed the wall of the cyst did contain cancer cells. Additionally, the slides were sent out for a “blind review” and that reviewer diagnosed “malignant neoplasm.”
Medical oncologists consulted by the defense asserted that the patient’s presentation was unusual for pancreatic cancer and questioned whether the delay in diagnosis altered the patient’s outcome.
Disposition
This case was settled on behalf of Pathologist A.
Risk management considerations
According to the Physician Insurers Association of America (PIAA) Closed Claims data, diagnosis error is defined as a failure to diagnose or an incorrect diagnosis. “The most prevalent alleged medical misadventure in pathology claims was diagnostic error. This misadventure was reported as the primary issue in 58% of claims reported between 1985 and 2009. For claims closed in 2009 only, error in diagnosis was again named the primary misadventure, reported in 69% of pathology claims.” (1)
Among the 1,732 pathology claims closed and reported to the PIAA between 1985 and 2009, more than 52% involved microscopic examination. In 2009, the most prevalent procedure was microscopic examination; there were19 claims and more than $2.2 million paid in indemnity.
In reviewing pathology claims by severity of injury, the patient died in 23.8% of the claims reported to PIAA between 1985 and 2009. Approximately 28% of the toal indemintiy was paid on behalf of pathologists for claims in which the patient died.
A total of 16 paid pathology claims were reported to the PIAA in 2009. Total indemintiy paid for these claims amounted to more that $6.5 milllion. The average indeminity paid was $408,281.
Accuracy in diagnosis is essential in surgical pathology. In a 2005 study published in the American Journal of Clinical Pathology found that “disagreements in diagnosis between pathologists have been equated with diagnostic accuracy and error.” (2) Disagreement rates vary widely and there has been little follow-up information published concerning cases with disagreement and effort to correlate the results of disagreement with this additional information. In many of the cases, the original diagnosis was indeed correct. This suggests that pathology departments should track their interdepartmental consultation rate and error rate (one in which the actual pathology diagnosis was subsequently found to be incorrect) to help eliminate this confusion.
Pathology groups may want to consider increased use of inter-departmental consultation for challenging specimens. In cases of disagreement between pathologists (on inter-departmental consultation) use of extra-departmental consultation for a second option may be helpful to resolve disagreements in diagnosis.
In this case, the surgery was performed on a Thursday and the pathology report was finalized on Monday. It may be helpful for pathology departments and pathologists to examine time demands placed on the pathology department on specific days and consider additional staffing if increased workload is found to exist on specific days of the week.
Communication between the surgeon and the pathologist is important for correct surgical pathology. Surgeons and pathologists should have the opportunity for open discussion when surgical pathology differs from the surgeon’s expectation.
In cases where a previous pathology review has been done, consider requesting previous slides for comparison before issuing a final pathology report. Review of the previous FNA biopsies may have alerted Pathologist A that there had been varying opinions on specimens and encouraged closer review of the specimen before the report was finalized.
Sources
1. Physician Insurers Associations of America. Semi-Annual Data Sharing Report. Pathology. 2010 Edition. January 1, 1985 to December 31, 2009. Rockville, MD.
2. American Journal of Clinical Pathology. 2005; 124:878-882
These closed claim studies are based on an actual malpractice claims from TMLT. These cases illustrates how action or inaction on the part of physicians led to allegations of professional liability, and how risk management techniques may have either prevented the outcome or increased the physician’s defensibility. These studies have been modified to protect the privacy of the physicians and patients.