Doctors Company Advisory to Pathologists on Avoiding Malpractice Liability
The Doctors Company is the endorsed malpractice insurer for the CSP. Dr David Troxel, the Doctors Company medical director, is a pathologist and has provided us with a copy of his article on metastatic squamous carcinoma. We have reprinted below a copy of his article for your consideration.
Metastatic Squamous Carcinoma misdiagnosed as Branchial Cleft Cyst
The misdiagnosis of metastatic well-differentiated squamous carcinoma as a branchial cleft cyst is an on-going cause of pathology malpractice claims. I've reviewed approximately 15 such claims between 1995 and 2010.
The patients are typically young males (ages 30 to 45) in an age group where "cancer" is not the first diagnostic consideration. In addition, branchial cleft cyst is often the clinical diagnosis, contributing to the pathologists "mindset" when examining the slides. At the time of misdiagnosis there is usually no known primary carcinoma - contributing to the failure to consider a metastasis. In most cases an occult primary is subsequently found in the oropharynx or nasopharynx. The squamous carcinomas are cystic and usually well-differentiated - features further contributing to the misdiagnosis of branchial cleft cyst, particularly in a young patient.
1.) Do not make a diagnosis of branchial cleft cyst without first considering the differential diagnostic possibility of metastatic well-differentiated, cystic squamous carcinoma - regardless of patient age and clinical diagnosis.
2.) Look carefully for cytologic atypia in the lining squamous epithelium. If present, consider immunostains for HPV. Alert the clinician to the need for thorough work-up to exclude an occult primary in the head or neck - and particularly at the base of the tongue or tonsillar fossa, since HPV+ cancers arising in these locations may have cystic metastases to cervical lymph nodes.
Be hesitant to make an FNA diagnosis of "consistent with branchial cleft cyst" based on a few bland squamous cells and macrophages in sparsely cellular fluid aspirated from a neck mass.