A Clinically Asymptomatic Patient with a Flowcytometry Profile of Mycosis Fungoides/Sezary Syndrome

Introduction: 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. They are considered separately on the basis of clinical features and cell of origin. Flowcytometry plays an important role in the diagnosis of MF/SS with a characteristic immunophenotypic expression of a lack of CD 7 as a common feature in all stages of the disease. Our case is a clinically asymptomatic patient with a flowcytometric pattern of Mycosis fungoides/Sezary syndrome. There is no documentation of such a case in the literature.

Case: A 55 - year – old male presented with persistent lymphocytosis. Investigations revealed a Hb of 15.5 g/dl, ESR 03 mm/1st hour, platelet count of 178,000/cu mm, total WBC count of 10,700/cu mm and an absolute lymphocyte count of 7000/cu mm (62%). The serum protein electrophoresis was normal. LDH was 149 IU/L (150-250) IU/L. A chest X-ray showed no pathology.

The patient was followed up for a period of five months with full blood counts (FBC), monospot test, ultrasound scan of abdomen, full body CT scan, LDH level and viral studies. During this period, the lymphocytosis persisted. Serial absolute lymphocyte counts were 6332/cu mm, 4918/cu mm, 5749/cu mm, 6890/cu mm and 7820/cu mm. Viral studies revealed CMV IgG antibody positivity and Hepatitis A (HAV) IgG positivity. Studies for HIV were negative. Monospot test for infectious mononucleosis was negative. Ultrasound scan of abdomen and full body CT scan were normal. Blood picture revealed small to medium sized lymphocytes with scanty cytoplasm. Bone marrow examination revealed a reactive marrow with a normal lymphocyte count of 15-20%. Flowcytometry was performed using peripheral blood and bone marrow samples 5 months apart.

Results: Flowcytometry of peripheral blood and bone marrow revealed that T-lymphocytes percentage was 92.0%and 82.0%, respectively. The immunophenotypic results for both blood and bone marrow revealed almost identical findings on LST (Lymphoid Screening Tube) and TCLPD (T Cell Lymphoproliferative Disorder) panels showing bright positivity of smCD3, CD4, CD2, TCRαβ, CD5 and dim positive CD8. Negative results were CD7, TCRγδ, CD25, CD26 and CD4+/ CD8+ ratio was 3.0/2.3 respectively.

Conclusion: The criteria of International Society of Cutaneous Lymphomas (ISCL) and the European Organization for Research and Treatment of Cancer (EORTC) to stage Mycosis fungoides and Sezary Syndrome were not present in our patient who was asymptomatic but showed a typical immunophenotypic pattern of MF/SS.