Mycosis Fungoides (MF) is the most common type of cutaneous
T-cell lymphoma, accounting for 50% of all cutaneous lymphomas. Sezary Syndrome
(SS) and MF are closely related T-cell neoplasms that are considered separately
based on clinical features and cell of origin. Despite their differences, both
conditions can be challenging to diagnose, particularly in the absence of
clinical symptoms. Flow cytometry plays a crucial role in the diagnosis of MF
and SS, with a characteristic immunophenotypic expression that includes the
lack of CD7 as a common feature in all stages of the disease. This diagnostic
tool is invaluable in identifying the specific markers that differentiate these
lymphomas from other T-cell disorders. In clinical practice, it is not uncommon
to encounter patients who are asymptomatic yet exhibit a flow cytometric
profile indicative of MF/SS. Such cases are rarely documented in the
literature, highlighting the need for increased awareness and detailed analysis
of these silent presentations. Persistent lymphocytosis, for example, can be an
initial finding that warrants further investigation through flow cytometry. The
immunophenotypic profile of MF/SS typically includes bright positivity for
markers such as smCD3, CD4, CD2, TCRαβ, and CD5, with dim positivity for CD8.
Conversely, markers such as CD7, TCRγδ, CD25, and CD26 are usually negative.
The CD4+/CD8+ ratio is often altered, reflecting the underlying pathophysiology
of these lymphomas. Despite the absence of clinical symptoms, such as those required
by the International Society of Cutaneous Lymphomas (ISCL) and the European
Organization for Research and Treatment of Cancer (EORTC) for staging MF and
SS, the presence of a typical immunophenotypic pattern on flow cytometry is
significant. It underscores the importance of utilizing advanced diagnostic
techniques to uncover and manage silent diseases effectively. By understanding
the flow cytometry indicators and their implications in the context of MF/SS,
clinicians can better identify and treat patients who might otherwise remain
undiagnosed until the disease progresses to more advanced stages. This
knowledge is critical for early intervention and improved patient outcomes in
cutaneous T-cell lymphomas.
Author(s) Details
Dr. (Ms). C. C. Kariyawasan (MBBS, Diploma in Pathology,
MD in Haematology)
Sri Jayewardenepura General Hospital, Thalapathpitiya
Nugegoda, Sri Lanka.
B. L. T. Balasuriya (B.Sc in Medical Laboratory Sciences
(Special), M.Phil. (Haematology-reading)
Sri Jayewardenepura General Hospital, Thalapathpitiya Nugegoda, Sri Lanka.
S. A. C. D. Ranatunga (B.Sc in Medical Laboratory
Sciences (Special), M.Sc in Molecular Pathology)
Sri Jayewardenepura General Hospital, Thalapathpitiya
Nugegoda, Sri Lanka.
Please see the book here :- : https://doi.org/10.9734/bpi/dhrni/v1/983
