I guess the moral of the story is that if it involves a human being, be
warned.

23 Jul 2005

Pathology is the medical specialty that deals with the examination of
tissues and cells under the microscope in order to arrive at a
diagnosis. When it comes to cancer, a pathological diagnosis is the gold
standard that indicates the presence or absence of cancer, the type of
cancer, and its classification. Because therapeutic decisions are based
on the presumed reliability of the pathology diagnosis, a misdiagnosis
can result in unnecessary, harmful and aggressive therapy or inadequate
treatment.

Unfortunately, medical studies over the last two decades have
demonstrated that this gold standard is not consistently reliable. In
fact, multiple studies have demonstrated discrepancy rates of up to 30%
with an average of approximately 10%. A "discrepancy" happens when one
pathologist renders a diagnosis and another pathologist looks at the
same material and renders a different opinion. See for example, Gupta D,
Layfield LJ. Am J Surg Pathol. 2000 Feb;24(2):280-4. Prevalence of
inter-institutional anatomic pathology slide review: a survey of current
practice.

Here are some examples from the medical literature:

-- Bladder Cancer - Wrong Pathology Would Have Led to Five Unnecessary
Cystectomies: The pathology of 97 patients (131 specimens) with
suspected urothelial carcinoma of the bladder was reviewed. Twenty-four
of the 131 specimens "exhibited significant discrepancies." This
included two patients who showed no evidence of tumor. As a result of
the review, five radical cystectomies were avoided.
Coblentz TR, Mills SE, Theodorescu D. Cancer. 2001 Apr 1;91(7):1284-90.
Impact of second opinion pathology in the definitive management of
patients with bladder carcinoma.

-- Prostate Cancer - Wrong Pathology Would Have Led to Six Unnecessary
Prostatectomies: A total of 535 men referred for radical prostatectomy
were reviewed. Seven (1.3%) of the men were found to have a benign
pathology. "Upon subsequent clinical work up, six of seven men were
considered not to have adenocarcinoma, and their surgery was cancelled."
Epstein JI, et al., Am J Surg Pathol. 1996 Jul;20(7):851-7. Clinical and
cost impact of second-opinion pathology. Review of prostate biopsies
prior to radical prostatectomy.

-- Brain Tumors - Pathologists Often Disagree With Themselves or Others
Pathologists agreed with their original diagnosis only 51.43% for
anaplastic astrocytomas, 74.73% for glioblastoma multiforme, and 65.22%
for low-grade astrocytomas. Pathologists agreed with other pathologists
only 62.41% for glioblastomas, 36.04% for AA, and 57.14% for low-grade
astrocytomas. Mittler MA, et al., J Neurosurg. 1996 Dec;85(6):1091-4.
Observer reliability in histological grading of astrocytoma stereotactic
biopsies.

-- Breast Cancer - Different Treatment Recommendations 43% of the Time:
Seventy-five women with a total of 77 breast lesions were examined. The
reviewing panel disagreed with the treatment recommendations 43% of the
time (32 cases). The disagreements included breast-conservation therapy
instead of mastectomy (13 patients) and different treatment based on a
"major change in diagnosis on pathology review. (3.9%)."
Chang JH, et al., Cancer. 2001 Apr 1;91(7):1231-7. The impact of a
multidisciplinary breast cancer center on recommendations for patient
management: the University of Pennsylvania experience.

-- Ovarian Cancer - 12.7% Did Not Have Ovarian Cancer The medical
records and pathology slides of 339 women diagnosed with ovarian cancer
were reviewed. Forty-three women (12.7%) were discovered not to have
ovarian cancer. (28 had other types of cancer and 15 had benign tumors.)
McGowan L, Norris HJ. Surg Gynecol Obstet. 1991 Sep;173(3):211-5. The
mistaken diagnosis of carcinoma of the ovary.

-- Soft Tissue Lesions - Benign Considered Malignant and Malignant
Considered Benign: In this study 266 cases of soft tissue lesions were
reviewed. A major discrepancy was found in 25% of cases. Of these
discrepancies, 45% consisted of benign lesions diagnosed as sarcomas,
and 23% were sarcomas diagnosed as benign tumors.
Arbiser ZK, Folpe AL, Weiss SW. Am J Clin Pathol. 2001 Oct;116(4):473-6.
Consultative (expert) second opinions in soft tissue pathology. Analysis
of problem-prone diagnostic situations.
Getting the pathology wrong is not limited to the U.S. Other countries
have found similar problems. For example, in the United Kingdom, 413
cases of sarcoma were reviewed and the diagnosis was confirmed only 76%
of the time. The study concluded that "second opinion is essential in
cases of presumed sarcoma.to ensure that appropriate treatment is
selected."
Harris M, Hartley AL, et al., Br J Cancer. 1991 Aug;64(2):315-20.
Sarcomas in north west England: I. Histopathological peer review
Do You Need a Second Opinion?
The vast majority of pathologists are excellent physicians and that the
diagnoses they render are correct. However, a minority of cases benefit
from a second opinion. The problem, of course, is accurately identifying
which cases should get a second opinion. To read the rest of the story
go to http://www.cancermonthly.com

knowledge is power - growing old is mandatory - growing wise is optional
"Many more men die with prostate cancer than of it. Growing old is
invariably fatal. Prostate cancer is only sometimes so."
http://community.webtv.net/PALMER_ENT/doc