Although this looks like vitiligo or lichen
sclerosis et atrophicus, the presence of prominent epidermotropism
by large atypical lymphocytes makes mycosis fungoides likely.
Hypopigmented mycosis fungoides is a slow progressive
cutaneous T cell lymphoma. It is a rare clinical variant of
the disease. Described exclusively in dark skinned or asian
patients, it was first described by Ryan in 1973. There are
now about 106 reported cases of hypopigmented MF
Hypopigmented MF was more likely to occur in
younger patients. Persistent or unusual hypopigmented lesions
should be subjected to biopsy to avoid delay in the diagnosis
of MF, especially in children. It has a long latent period.
Generally, It has a good response to therapy
to
PUVA, UVB or topical mechloramine therapy.
However, recurrences are common. They have a biologically benign
course.
References:
Akaraphanth R, Douglass MC, Lim HW Hypopigmented
mycosis fungoides: Treatment and a 6½-year follow-up
of 9 patients J Am Acad Dermatol 2000;42:33-9
Ardigó M, Borroni G, Muscardin L,
Kerl H, Cerroni L Hypopigmented mycosis fungoides in Caucasian
patients: A clinicopathologic study of 7 cases J Am Acad Dermatol
2003;49:264-70
Comments from Members
Choon, Siew Eng FRCP, Department of
Dermatology, Hospital Sultanah Aminah, Johor Bahru, Malaysia
on Mar 4, 2004
I saw a 29-year-old Afro-Carribean man with
hypopigmented MF and have the pleasure of reading the HPE slides
personally. I think these 4 articles may be of interest to you,
two case reports in caucasians. Sitting in the Dermatopathology
Lab in St John's, London makes me wonder how many British are
walking about with MF (definitely more than estimated incidence
of 4/100000/year incidence) cos' we see so many MF slides per
week but so far only one hypopigment MF.
Ref:
- Landro et al: Pediatric Dermatol, Vol 14(6) Nov/Dec 1997
449-452
- Neuhaus: Pediatric Derrmatol, Vol 17(5) Sept/Oct 2000 403-406
- Robert: Br J dermatol Vol 139(2) Aug 1998 341-343
Khalifa Shaquie MD, PhD, Professor
of Dermatology, College of Medicine, University of Baghdad,
Baghdad, Iraq on Nov 12, 2004
In Iraq it is common to see the depigmentation
of vitiligo to pass through 2 stages. Stage I vitiligo appears
as a whitish-brown patches in colour before changing to stage
II vitiligo (milky-white in color). Histopathologically Stage
I vitiligo shows epidermal lymphocytic inflammatory reaction
with tendency to form Pautrier microabscesses in some instances.
The dermis also shows mild to moderate lymphocytic inflammatory
reaction in the majority of cases. Hypopigmented MF is a newly
described entity appears to share many features with stage I
vitiligo; characterised by childhood onset of dark skin people
with nonprogressive hypopigmented macules and good response
to PUVA therapy. In conclusion we think that many cases which
were diagnosed and treated as such are really a stage I hypopigmented
vitiligo. Full review article regarding this controversy will
be published in future. Regarding the present case we strongly
think it is a clinically and histopathologically a case of stage
I vitiligo rather than hypopigmented MF.
References
1.Sharquie KE.Stages of depigmentation in vitiligo. Iraqi Med.J
1988;36:47-50.
2.Sharquie KE. The histology and immunopathology of vitiligo.
PhD thesis. University of Sheffield, England 1982.
3.Sharquie KE, Mehenna SH,Al-Azzawi H and Naji A. Inflammatory
changes in vitiligo(stage I and II depigmentation).Am J Dermatopathology.
Vol.26(2) April 2004 pp 108-112.
Salai Jayakumar MD, Professor, Department of Dermatology,
Madras Medical College, Chennai, India on January 13,
2007
We are seeing many cases of Hansen's Disease and I think we
have to include hypopigmented mycosis fungoides in differential
diagnosis. The dermatologist from Baghdad's comment about early
vitiligo is quite interesting.
John Andrew Carlson MD, Professor,
Divisions of Dermatology and Dermatopathology, Albany Medical
College, Albany, NY. USA on January 25, 2007
I believe this case most likely represents hypopigmented MF
and not vitiligo.
While it’s true that vitiligo can mimic hypopigmented
mycosis fungoides, it’s not typical of vitiligo to show
scale, histologically, as seen in this case. In addition, lymphocytes
are few in vitiligo- present around superficial venules and
sparsely scattered in the lower half of the epidermis associated
with slight spongiosis. In this case, numerous lymphocytes are
found in the epidermis associated with obvious spongiosis; findings
that favor MF over vitiligo.
Not considered in the discussion of this case is the possibility
of pityriasis alba. Based on the histology, pityriasis alba
is more likely than vitiligo.
Analysis of melanocyte number, melanization of the epidermis
and immunophenotyping of the infiltrate could help differentiate
between these possibilties. Also, after 2+ years, has this eruption
progressed or remained stable despite therapy?
References [1-3]:
[1] Singh ZN, Tretiakova MS, Shea CR, Petronic-Rosic VM. Decreased
CD117 expression in hypopigmented mycosis fungoides correlates
with hypomelanosis: lessons learned from vitiligo. Mod Pathol.
2006 Sep;19(9):1255-60.
[2] Werner B, Brown S, Ackerman AB. "Hypopigmented mycosis
fungoides" is not always mycosis fungoides! Am J Dermatopathol.
2005 Feb;27(1):56-67.
[3] Sharquie KE, Mehenna SH, Naji AA, Al-Azzawi H. Inflammatory
changes in vitiligo: stage I and II depigmentation. Am J Dermatopathol.
2004 Apr;26(2):108-12.
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