Vol 43 # 2 June 2011 - Kma.org.kw

June 2011
KUWAIT MEDICAL JOURNAL 131
Fig. 1: Bluish purple lesion can be seen in the ring and little finger
nail beds
agent for nails. Nerve conduction study for upper limb
was normal. Unfortunately we could not perform MRI
for this patient. We told her not to use henna again and
come back to our department once the henna grows
out. She came back after five months for re-evaluation
when henna could not be seen anymore. We observed
the bluish purple discoloration under the nail beds
with nail deformities in the affected fingers (Fig. 1),
reconfirming the case clinically as a multifocal solitary
glomus tumor in a case of neurofibromatosis type 1.
Patient underwent surgery for removal of glomus
tumors from the affected two fingers as well as for two
nodules on the face for cosmetic reason on patient’s
request. Typical pearl like nodular glomus tumor was
visible during operation (Fig. 2) in left ring finger, but
not well-defined in left little finger. Histopathologically,
we found that the solitary lesions appeared mostly as
solid well-circumscribed nodules surrounded by a
rim of fibrous tissue. They contained endotheliumlined
vascular spaces surrounded by clusters of
glomus cells. The glomus cells were monomorphous
Fig. 3: The glomus cells with monomorphous round and polygonal
cells with plump nuclei and scant eosinophilic cytoplasm
Fig. 2: Solitary well circumscribed pearl like tumor can be seen on
the dissected flap
round or polygonal cells with plump nuclei and scant
eosinophilic cytoplasm (Fig. 3). Findings were similar
in both the removed glomus tumors. One of the
two nodules removed from the face showed typical
neurofibromatosis histopathologically, and another
showed sebaceous lesion. Postoperative follow up was
uneventful and the pain was relieved completely. Her
activities of daily life also improved dramatically.
DISCUSSION
Subungual glomus tumors are usually solitary and
the association of multifocal solitary glomus tumors
with neurofibromatosis type 1 has only rarely been
reported [5-7] .
Multifocal phalangeal glomus tumors in several
patients with neurofibromatosis type 1 suggest
that this is not an incidental association but that
neurofibromatosis type 1 patients have an increased
incidence of glomus tumors. Smet et al hypothesized
that glomus cells are of neural crest origin [8] . Neural
crest stem cells can be isolated from mammalian fetal
peripheral nerves. Neural crest stem cells form three
different cell types in culture - neurons, Schwann
cells, and smooth muscle-like myofibroblasts [9] . These
myofibroblasts are positive for alpha-smooth muscle
actin and might be the precursors of the alpha-smooth
muscle actin positive glomus cells in the glomus organ
of the nail bed. Therefore, it is possible that a second
hit in the neurofibromatosis type 1 gene in a alphasmooth
muscle actin positive glomus cell results in
a glomus tumor in neurofibromatosis type 1 patients
in a similar way as a second hit in a Schwann cell is
responsible for a neurofibroma [8] .
Average delay in the diagnosis of glomus tumor
is two and half years [10] . In another study, the time to
surgery from the onset of symptoms ranged from six
months to 30 years [11] . In our patient, diagnosis may
have been delayed due to the habit of using henna
by the patient, camouflaging the characteristic bluish