Melanoma claims: from overreaction to oversight
August 2002 Alvin Ring, MD
Marva West Tan, RN, ARM
Following are analyses of closed melanoma claims managed by The
St. Paul and MMI Companies Inc., St. Paul, Minn. Some facts may have
been changed in the following cases to protect confidentiality.
Case 1 - Misdiagnosis of malignant melanoma
Allegation: Misdiagnosis of atypical Spitz
nevus of right buttock as malignant melanoma and fear of death for
four-and-a-half years.
Defendants: Pathologist and pathology laboratory.
Facts of case: A 37-year-old woman had a
mole removed from her right buttock in September 1991. The mole
was sent to a pathology laboratory for analysis. Pathologist X’s
report stated: "Malignant melanoma, superficial spreading pattern,
largely in situ with focal invasion abutting on the reticular dermis
(Clark’s level III). The lesion measures 0.5 mm in thickness and
is incompletely excised, right buttock." The pathologist noted that
a limited re-excision (0.5 to 1.0 mm) is indicated for the lesion.
Three other pathologists in the practice concurred in the diagnosis
and their names appear on the report.
For approximately four-and-a-half years following the melanoma
diagnosis, the patient became obsessed with dying and believed the
condition would cause her demise. She had four or five additional
moles removed, became depressed, was unable to continue her usual
activities, and, consequently, gained weight.
In spring 1996, the patient changed health insurance and her new
physicians re-analyzed her condition. They reviewed the original
specimen from the September 1991 analysis. While the outside pathologists’
letters or reports are not contained in the claims file, a summary
indicated that one plaintiff pathologist expert diagnosed the original
lesion as atypical Spitz nevus and another pathologist expert diagnosed
the lesion as atypical Spitz nevus and recommended wide excision.
Legal action: Shortly after receiving this
new opinion regarding her diagnosis, the patient requested mediation
by the state compensation fund. (Mediation is an alternative dispute
resolution mechanism whereby a neutral third party facilitates a
mutually acceptable agreement. The process, the composition of the
mediation panel, and whether or not the findings are binding vary
by state.) The mediation was scheduled for approximately two months
later. The mediation panel was chaired by an attorney and consisted
of a neutral pathologist, a layperson, the patient or claimant and
her attorney, and the respondents or defendants, which were Pathologist
X and the pathology laboratory and its attorneys and representatives
of its insurers.
The claimant’s allegations were presented as detailed above. The
defense’s position was that the consensus of the pathologists who
had seen the slide of the specimen was that the initial reading
was correct and Pathologist X’s report is within the standard of
care. Even the claimant’s expert noted that the diagnosis is an
extremely close call. Moreover, the defense noted that if the lesion
is atypical Spitz nevus, the claimant received proper treatment.
The claimant’s anxiety, while understandable, is an over-reaction,
according to the defense. Medical records indicate that the claimant’s
physicians informed her that her prognosis was very good.
The patient countered that she had not been informed she had a
98 percent chance of survival.
After closed discussion, the mediation panel supported the defense.
No suit was filed, and the statute of limitations expired on this
case. Losses were limited to defense costs.
Clinical issues and standard of care: This
case is overshadowed by social and patient-centered issues, mainly
the patient’s reaction to a diagnosis of malignancy, which was exacerbated
by her knowledge of two acquaintances who had died of melanoma.
Nevertheless, issues surround the diagnosis and the interaction
of the pathologists with the clinicians and the clinicians with
the patient, as well as the informed consent.
Many pathologists would agree that Pathologist X handled this
case appropriately. They would also agree with his comment that
the lesion was incompletely excised and his suggestion that re-excision
was indicated. (Although stating in the report that a 0.5-cm to
1-cm re-excision was indicated may be encroaching on the clinicians’
prerogatives.) Most pathologists also would have described the microscopic
findings leading to a diagnosis of malignant melanoma and, if the
lesion was unusual, the differential diagnosis. The report did not
contain notations regarding discussions with the surgeon.
A positive feature of the report is a statement that the diagnosis
was made in consultation with three other pathologists in the group.
Because there is no discussion of differential diagnosis or difficulty
in making a diagnosis, it is assumed that the four pathologists
were confident the diagnosis was correct and did not consider other
alternatives, which might have led to outside consultation by an
expert in the field. The fact that one expert pathologist who subsequently
reviewed the case called the lesion atypical Spitz nevus but suggested
additional wide excision demonstrates that even expert dermatopathologists
sometimes have difficulty with these lesions.
A November 1996 editorial in Human Pathology, titled "Discordance
among expert pathologists in the diagnosis of melanocytic neoplasms,"
described a study in which a panel of 11 expert pathologists was
convened and reviewed 37 classic melanocytic neoplasms. The experts
were in agreement about whether the neoplasms were benign or malignant
in only 30 percent of the cases.1
A 1999 study reported similar marked disagreement among experts
in the differential diagnosis of melanoma and Spitz nevi.2
Recurrent Spitz nevi are even more problematic since the original
symmetry has been lost.
One series reported that 6.5 percent of all melanomas referred
to a consulting service were Spitz nevi, and that Spitz nevi represented
the majority of pathologically misdiagnosed melanomas. This study
stressed that greater clinical--pathologic communication may reduce
the frequency of diagnostic errors.3
Pathologists faced with difficult melanocytic lesions obviously
should seek expert advice if for no other reason than to show in
a court of law that such advice was sought. Discussions with an
expert also provide an educational opportunity. Disclaimers should
appear in the report if the lesion is a shave biopsy or incompletely
excised. From a practical viewpoint, re-excision may be reasonable,
even in a well-characterized Spitz nevus, because if it were to
recur in a previously biopsied area, the distortion and treatment-related
atypia might hinder diagnosis. Even sentinel lymph node excision
has been proposed selectively since metastasis to the sentinel lymph
node would confirm the diagnosis of malignant melanoma.4
Patient education: Patients may have unrealistic
expectations that the diagnostic process is easy or straightforward
in all situations. Helping patients develop realistic expectations
about diagnosis and treatment is important. The trust created during
these discussions may set the stage for better patient-physician
communication when unexpected outcomes occur. It is not clear in
this case why the patient’s initial contact with Pathologist X was
an attorney’s request for mediation rather than a personal request
to discuss the differences in the diagnoses.
Patients with cancer diagnoses obviously want to understand their
prognosis, treatment options, medications, and after-care. They
often need to have information repeated and to have questions answered.
Physicians, however, do not need to provide all the information
themselves. Involving other members of the health care team and
using preprinted materials or referring interested patients to online
cancer information sources are options.
CAP TODAY consulted with two dermatopathologists about
this issue. Following is their opinion: We believe pathologists
seldom have access to patients and typically do not want to interfere
with the -clinician-patient relationship. Pathologists need to protect
themselves from legal action by using lawyer-approved disclaimers
and hedges and by implementing procedures to track clinical information
and to ensure accurate record-keeping.
We recommend that regular Spitz nevi in adults be excised. One
of the dermatopathologist’s labs uses the disclaimer "although controversial,
complete excision with a margin of normal skin is recommended."
The lab uses numerous disclaimers, such as, "If this specimen represents
just part of a significantly larger lesion, the findings may not
be representative of the entire lesion." We don’t usually diagnose
a straight out Spitz nevus if the lesion is a shave specimen in
an adult, and we will usually hedge to force the clinician to take
it off.
References
1. Ackerman AB. Discordance among expert pathologists in the
diagnosis of melanocytic neoplasms. Ed. Hum Pathol. 1996;27:1115-1116.
2. Barnhill RL, Argenyi ZB, et al. Atypical Spitz nevi/tumors:
lack of consensus for diagnosis, discrimination from melanoma, and prediction
of outcome. Hum Pathol. 1999;30(5):513-520.
3. Orchard DC, Dowling JP, Kelly JW. Spitz nevi misdiagnosed
histologically as melanoma. Australia Journal. 1997; 38(1):12-14.
4. Lohmann CM, Coit DG, et al. Sentinel node biopsy in patients
with diagnostically controversial spitzoid melancytic tumor. Am J Surg Pathol.
2002; 26: 47-55.
Case 2 - Misdiagnosis of malignant melanoma
Allegation: Desmoplastic melanoma misdiagnosed
as nodular fasciitis.
Defendants: Pathologist No. 1, Pathology
Laboratory No. 1, Pathologist No. 2, Pathology Laboratory No. 2,
and plastic surgeon.
Facts of case: The patient, a 31-year-old
woman, had a lesion removed from her left anterior chest wall by
her family physician on March 12, 1993. The specimen was sent to
laboratory No. 1. On March 14, 1993, Pathologist No. 1 issued a
report of "skin biopsy, left anterior chest, actinic lentigo." Following
is the sequence of events:
- The lesion recurred and the patient was referred to a plastic
surgeon that treated her from August 1994 to May 1996. The surgeon
apparently never received nor reviewed the family practitioner’s
medical records or the March 1993 pathology report.
- August 24, 1995 The plastic surgeon performed an "excision
of recurrent keloid scar of the left upper anterior chest in lateral
infra clavicular area." The specimen was sent to lab No. 2.
- August 29,1995 Pathologist No. 2 issued a report of "proliferating
fibroblasts and chronic inflammatory cells most consistent with
nodular fasciitis."
- December 28, 1995 The plastic surgeon performed another
"excision of recurrent nodular fasciitis of left upper anterior
lateral chest and left lateral clavicular area" and again sent
the specimen to lab No. 2.
- December 29, 1995 Pathologist No. 2’s report noted "spindle
cell proliferation with chronic inflammatory infiltrate consistent
with nodular fasciitis, and focal foreign body-type giant cells
and suture material consistent with previous excision." At the
time of the August 1995 and December 1995 reports, Pathologist
No. 2 was not aware of Pathologist No. 1’s 1993 report.
- April 1996 Pathologist No. 2 was informed by the plastic
surgeon that the patient had a large axillary mass and apparently
learned of the 1993 pathology report. Pathologist No. 2 then requested
a S-100 stain on the 1995 specimens and contacted lab No. 1 for
slides, paraffin block, and a faxed copy of the 1993 pathology
report. The S-100 stain was strongly positive, and Pathologist
No. 2 felt that Pathologist No. 1’s 1993 report indicated a "previous
melanocytic lesion."
- May 10, 1996 Pathologist No. 2 issued amended pathology
reports from August 1995 and December 1995 as "desmoplastic melanoma,
Clark’s level IV."
- May 23, 1996 The patient underwent a wide excision of
skin and subcutaneous tissue from the lateral chest wall. The
tissue demonstrated residual desmoplastic melanoma as well as
metastasis to one of 21 axillary lymph nodes.
- June 28, 1996 The patient had an axillary node dissection
that showed reactive fibrosis (doubt recurrence of desmoplastic
mela-noma) and foreign body giant cell reaction. An oncologist
treated the patient with interferon.
- February 6, 1997 The patient underwent a radical neck
dissection for recurrence of malignant melanoma. Pathology showed
metastatic desmoplastic malignant melanoma with 21 negative cervical
lymph nodes.
- March 18, 1997 A bone biopsy of the right femur showed
fragments of marrow tissue with fragments of desmoplastic malignant
melanoma, metastatic.
Legal action: In May 1997, the two pathologists
and the two pathology laboratories received notice from the plaintiff’s
attorney of intent to file a medical malpractice action. The plastic
surgeon subsequently was added to the action. The plaintiff’s allegations
included misdiagnosis of cancer and delay of diagnosis leading to
a loss of chance of cure. The plaintiff’s pathology expert stated
that the pathologists and pathology laboratories breach-ed the standard
of care, thereby failing to correctly diagnose cancer and failing
to correctly report cancer to the treating physician.
The defense expert pathologist for Pathologist No. 2 said the
latter did not deviate from the standard of care and that the outcome
of the disease was already determined by 1995. (The latter element
of that opinion speaks to the matter of causation. The elements
of a medical malpractice tort include not only the requirement that
the standard of care must be breached but also that the breach must
have caused the plaintiff’s damages.) A different insurer and a
different law firm represented Pathologist No. 1, and expert witness
information is not available regarding that clinician’s practice.
The plaintiff’s deposition was videotaped to preserve testimony
following court approval. (Videotaped depositions are sometimes
done when patients are terminal or otherwise may not be available
for a court appearance.) The plaintiff made a sympathetic presentation
on deposition.
Multiple defendants represented by different insurers and law
firms that did not agree on an approach to the defense complicated
this case. Finger-pointing among defendants regarding relevant clinical
information not being shared further weakened the defense’s case.
This claim was settled in February 1998 in the middle ranges on
behalf of all defendants.*
Clinical issues and standard of care: This
case exemplifies several issues in diagnostic error, including failure
to consider a diagnosis, pursuing a wrong hypothesis or narrowed
diagnostic path, failure to follow through, and bad information.
In 1993, Pathologist No. 1 reported "actinic lentigo." Upon recurrence,
Pathologist No. 2 issued a report of "proliferating fibroblasts
and chronic inflammatory cells, most consistent with nodular fasciitis."
In December 1995, another recurrence led to the repeat diagnosis
of nodular fasciitis.
It wasn’t until May 1996, upon learning of a large axillary mass,
that Pathologist No. 2 requested an S-100 stain. The stain was strongly
positive and the pathologist issued an amended pathology report
stating "desmoplastic mela-noma, Clark’s level IV." In other words,
neither Pathologist No. 1 nor No. 2 considered the diagnosis of
desmoplastic melanoma until metastasis had developed. Having pursued
the hypothesis that the lesion was a proliferative fibroblastic
lesion, Pathologist No. 2 offered the diagnosis of nodular fasciitis
and the recurrence as excision of recurring nodular fasciitis. This
diagnosis was apparently influenced by the plastic surgeon’s clinical
diagnosis of recurrent keloid scar. The plastic surgeon and pathologist
had not reviewed the medical records and pathology report from March
1993.
Desmoplastic melanomas, especially in their earlier phases, present
significant diagnostic difficulties for the pathologist. They tend
to be amelanotic, and atypia may be so minimal that distinctions
between tumor cells and activated fibro-blasts may not be apparent.
Superficial biopsies may be misdiagnosed as benign lentiginous lesions,
or if the melanocytic component is overlooked, as fibromatosis or
fibrohistiocytic tumor.1,2 Alternatively,
the spindle cell component may suggest a Spitz nevus, cellular scar,
or nerve sheath tumor. Because desmoplastic melanomas are rare compared
to common fibrohistiocytic lesions, the diagnosis may not be considered,
and immunostains for S-100 protein may not be performed. The lymphoid
reaction, which may be a tip-off, tends to be at the advancing edge
of the lesion and may not be seen in superficial biopsies, or it
may be misdiagnosed as nonspecific inflammation in a deeper biopsy.3
The first step in considering the diagnosis of desmoplastic melanoma
is a careful search for lentiginous and junctional components, especially
in actinically damaged skin.2-4
A greater degree of atypia in the deep dermal and subcutaneous components
or single files of atypical spindle cells among sclerotic collagen
bundles should be a clue. Unfortunately, clinical information or
diagnoses, such as scar or hypertrophic scar, supplied by dermatologists
or surgeons in these frequently amelanotic lesions are not helpful
or may even be misleading.
Because most desmoplastic mela-nomas are variants of lentigo maligna
melanoma, history of a lentiginous lesion with recurrence is helpful,
especially in sites of actinic exposure after the age of 40, though
not exclusively. Asymmetry may help differentiate the lesion from
Spitz nevus. Neurotropic growth is another helpful common occurrence
in desmoplastic melanomas,2-4
as is invasion of deep vascular channels. Diagnoses of recurrent
scars and fasciitis should be cause for concern.
The HMB-45 stain, which many pathologists use in the diagnosis
of melanoma, usually will be negative. The S-100 immunostains, however,
are generally positive.
Issues in diagnostic error: Human factors
research indicates that there are recurrent mechanisms in diagnostic
error, including those mentioned previously, which are failure to
consider a diagnosis, pursuing a wrong hypothesis or narrow diagnostic
path, failure to follow through, and bad information.
The failure to communicate relevant clinical information was a
quality weakness and a liability in this case. Patients generally
have multiple clinicians involved in their care. Better systems
should be implemented for sharing clinical information among a patient’s
caregivers. Pathologists should have a system to pursue additional
clinical information when they have questions about the limited
data supplied in the request for specimen analysis.
CAP TODAY’s two consultant dermatopathologists offer another
opinion: We do not practice with the assumption that the clinician
will provide accurate, or any, clinical information. In some cases,
a doctor may not even record why a procedure is being performed.
One of the dermatopathologist’s labs requests a previous biopsy
report in all cases of scar. The clinician’s office may deny a previous
history. However, you will have a record that you made such a request.
References
1. Longacre TA, Egbert BM, Rouse RV. Desmoplastic
and spindle-cell malignant melanoma. An immunohistochemical study.
Am J Surg Pathol. 1996;20(12):1489-1500.
2. Egbert B, Kempson R, Sagebiel R. Desmoplastic
malignant melanoma. A clinicohistopathologic study of 25 cases. Cancer.
1988;62(9):2033-2041.
3. Anstey A, McKee P, Jones EW. Desmoplastic malignant
melanoma: a clinicopathological study of 25 cases. Br J Dermatol.
1993;129(4):359-371.
4. Jain S, Allen PW. Desmoplastic malignant melanoma
and its variants. A study of 45 cases. Am J Surg Pathol. 1989;13(5):358-373.
Susan Tannenbaum, MD, chair of the CAP Insurance Committee, concludes:
Malignant melanoma is a serious and controversial subject. Experts
sometimes differ on the best way to protect against liability in
such cases. The experts do, however, agree that one must be diligent
in documenting that every effort was made to render the proper diagnosis.
This often includes seeking and documenting an expert second opinion.
* For purposes of this article, middle ranges are from $100,000
to $500,000.
Dr. Ring is medical director of laboratories, Silver Cross Hospital, Joliet,
Ill., and clinical professor of pathology, University of Illinois College of
Medicine. He is a member of the CAP Insurance Committee. Tan is a former senior
communicator, health care risk services, The St. Paul.
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