Hodgkin Lymphoma in a patient with mycosis fungoides: molecular evidence for separate cellular origins

Concomitant B Hairy Cell Leukemia and Mycosis Fungoides in an Elderly Man

The development of both a T- and B-cell lymphoproliferative disorder in one patient is an unlikely coincidence due to the low prevalence of each malignancy. We report a 65-year-old man with a previously documented history of B hairy cell leukemia, who presented with a new-onset acneiform eruption of his scalp, face, trunk, back, and extremities. Routine pathology of the skin lesions with immunohistochemical stains and molecular studies were consistent with a folliculotropic mycosis fungoides. B hairy cell leukemia and mycosis fungoides occurring in the same patient seems to be a rare phenomenon with only 5 cases reported in the literature.

High frequency of primary cutaneous lymphomas associated with lymphoproliferative disorders of different lineage

In patients suffering from primary cutaneous lymphomas, secondary malignancies of various origin may develop. However, the frequency of a second neoplasm deriving from another lymphoid lineage is still unclear and may be underestimated. We screened all our patients with primary cutaneous lymphomas from a 4-year recruitment period for a coexisting secondary lymphoproliferative disorder. The cohort comprised of a total of 82 patients with primary cutaneous lymphomas, 62 with primary cutaneous T-cell lymphoma (CTCL), 18 with primary cutaneous B-cell lymphomas, and two with CD4+/CD56+ hematodermic neoplasm/blastic lymphomas. Seven patients (8.5%) were identified with a coexisting lymphoma of a different lymphoid lineage. Four patients with Sézary syndrome (SS) suffered from systemic B-cell lymphoma. Two of these developed SS after chemotherapy of their B-cell lymphoma. The other three patients with various types of skin lymphomas (SS, Mycosis fungoides [MF], primary cutaneous marginal zone lymphoma) developed Hodgkin's disease (hairy cell leukemia). Our data indicate that patients with primary cutaneous lymphomas have an elevated risk for the development of a secondary lymphoproliferative disorder even without previous chemotherapy. Possible explanations for this association include a genetic predisposition, alterations in early progenitor cells, underlying viral infections, and/or stimulation of a B-cell clone by the malignant helper T cells of the primary CTCL and vice versa.

Mycosis fungoides associated with B-cell malignancies

BACKGROUND

The coexistence of mycosis fungoides, a peripheral T-cell lymphoma, and B-cell malignancies or Hodgkin's lymphoma in the same patient is unusual. Most descriptions are isolated case reports and case series are strikingly sparse.

OBJECTIVES

To detect cases of mycosis fungoides associated with B-cell malignancies or Hodgkin's lymphoma and to analyse the characteristics of and the interplay between the lymphoproliferative neoplasms.

METHODS

Patients with mycosis fungoides who had B-cell malignancies or Hodgkin's lymphoma were selected from among 398 patients either treated or followed up in two tertiary medical centres during a 7-year period.

RESULTS

Eleven patients with mycosis fungoides and B-cell malignancy were detected (seven of non-Hodgkin's lymphoma, three of chronic lymphocytic leukaemia, one of multiple myeloma). No case of Hodgkin's lymphoma was found. In seven patients the mycosis fungoides preceded the B-cell malignancy whereas in four it was the B-cell malignancy which occurred first. The time elapsed between onset of the two malignancies ranged from 4 to 22 years (average: 12 years). Patients who had mycosis fungoides as the first neoplasm presented with earlier stages of mycosis fungoides (four of seven: IA, three of seven: IB) than those who had mycosis fungoides as their second neoplasm (of four, one: IB, one: folliculotropic, two: IIB). Among the four patients in whom the appearance of mycosis fungoides followed the B-cell malignancy, three had been treated with multiagent chemotherapy. Two patients who presented with early-stage mycosis fungoides (IA) as the first lymphoma developed mycosis fungoides tumours after becoming immunosuppressed. In two patients infiltrates composed of both malignant T- and B-cell populations were found in a single biopsy. One showed two distinct populations of the malignant cells in the skin tumour, thus constituting a classical composite lymphoma of mycosis fungoides and chronic lymphocytic leukaemia, while in the other patient the two malignant populations of marginal B-cell lymphoma and mycosis fungoides (as evidenced by both phenotypic and genotypic findings) were intermingled.

CONCLUSIONS

This case series indicates that while the coexistence of Hodgkin's lymphoma and mycosis fungoides is extremely rare, the association of mycosis fungoides and B-cell malignancies is not as rare as reflected in the literature, with non-Hodgkin's lymphoma constituting the most common associated B-cell malignancy. In this series as well as in the cases reported in the literature mycosis fungoides usually preceded the development of B-cell malignancies, which may be in accordance with previous reports of an increased risk of developing a second haematological neoplasm. The importance of a competent immune system for patients with mycosis fungoides is well demonstrated in these cases. It is suggested that for greater precision the criteria for diagnosis of composite lymphoma of the skin should include both phenotypic and genotypic features.