Histiocytic lymphoma of breast responds to tamoxifen

Identification of the estrogen receptor beta as a possible new tamoxifen-sensitive target in diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma (DLBCL) is the most common lymphoma subtype. Despite the proven efficacy of combined immunochemotherapy (R-CHOP) in the majority of patients, ~40% of DLBCL patients do not respond or will relapse and consequently have a very poor prognosis. The development of targeted therapies has not improved patient survival, underscoring the need for new treatment approaches. Using an unbiased genome-wide CD20 guilt-by-association approach in more than 1800 DLBCL patients, we previously identified the estrogen receptor beta (ERβ) as a new target in DLBCL. Here, we demonstrate that ERβ is expressed at significantly higher levels in DLBCL compared to normal B cells, and ERβ plays a role in the protection against apoptosis in DLBCL. Targeting of the ERβ with the selective estrogen receptor modulator tamoxifen reduces cell viability in all tested DLBCL cell lines. Tamoxifen-induced cell death was significantly decreased in an ERβ knock-out cell line. The activity of tamoxifen was confirmed in a xenograft human lymphoma model, as tumor growth decreased, and survival significantly improved. Finally, tamoxifen-treated breast cancer (BC) patients showed a significantly reduced risk of 38% for DLBCL compared to BC patients who did not receive tamoxifen. Our findings provide a rationale to investigate tamoxifen, a hormonal drug with a good safety profile, in DLBCL patients.

Primary breast lymphoma

Primary breast lymphoma is a rare form of extranodal lymphoma, defined by the presence of a primary lesion within the breast with or without regional nodal involvement but no other extra-mammary sites of involvement. It comprises diverse histologic subtypes, but diffuse large B-cell lymphoma is the most common. In this review, we describe in detail the clinical features, diagnosis and staging, pathogenesis, risk factors and therapy of primary breast diffuse large B-cell lymphoma. We consider choice and number of cycles of chemotherapy, the indications for radiotherapy and discuss the need for central nervous system prophylaxis. We also provide a brief overview of the less commonly encountered histologic subtypes including marginal zone, follicular, Burkitt and breast implant associated anaplastic large cell lymphoma. We conclude with a suggested treatment approach and potential areas of future research.

Lymphomas of the breast: primary and secondary involvement

BACKGROUND

The involvement of the breast by lymphoma is a rare form of extralymph node lymphoma and represents either primary disease or systemic involvement. The authors hypothesized that screening mammography may influence the detection of lymphomatous involvement of the breast.

METHODS

All patients (n = 81 patients) who were diagnosed with lymphomatous involvement of the breast at the study institution between 1988 and 1999 were evaluated retrospectively.

RESULTS

Clinical information was available for 73 patients who could be classified into three major groups according to their diagnosis: primary breast lymphoma (PBL) (44%), breast involvement from disseminated disease at the time of initial diagnosis (29%), and recurrence of preexisting lymphoma to the breast (27%). The majority of PBL were of intermediate or high grade, and the majority of disseminated lymphomas involving the breast were of low grade. Lymphomatous recurrence to the breast was slightly more likely to be of intermediate grade rather than low grade. In 91% of patients, the diagnosis of lymphoma was made after the evaluation of a palpable mass. All patients who were identified after the evaluation of an abnormal screening mammogram (9%) had low-grade lymphomas. Of the 32 patients with PBL, screening mammography discovered only 1. Nineteen percent of patients with PBL also had a history of an autoimmune disorder.

CONCLUSIONS

These findings suggest that screening mammography has not altered substantially the detection of breast lymphoma. The clinical outcome of patients with breast lymphoma is dependent on histology and appears to parallel that of patients with lymphoma of similar histology involving other sites.

Primary breast lymphoma with skin involvement arising in lymphocytic lobulitis

Primary breast lymphoma is a rare tumour which has recently been associated with pre-existing lymphocytic lobulitis. We report a patient with lymphocytic lobulitis in whom the lymphoma recurred in the contra-lateral breast 5 years after the initial presentation, to be followed shortly afterwards by skin involvement. This progression illustrates the relationship between extra-nodal lymphomas and underlying autoimmune disease and the homing of lymphomas to related sites.

Breast lymphomas: a clinicopathologic review

Primary lymphoma is an uncommon tumor in the breast. Review of the literature shows two distinct clinicopathologic groups. One, which affects young women, is frequently bilateral, is often associated with pregnancy, and is a Burkitt-type lymphoma. The second group affects older women, is usually B-cell non-Hodgkins-type lymphoma, and presents clinical features identical to carcinoma of the breast. Three recent studies have suggested that up to half of the cases in the latter group belong to the category of lymphomas arising from the mucosa-associated lymphoid tissues. We have identified nine cases of primary lymphoma from the files of Guys Hospital Clinical Oncology Breast Unit in the 16-year period from 1974 to 1990. The clinical features have been reviewed and the tumors have been evaluated both on a morphologic and an immunohistochemical basis, and seven of nine of the cases have been screened for t[14;18] translocation using the polymerase chain reaction. All the tumors occurred in women older than 50 years and who presented with features of mammary carcinoma. One tumor was true histiocytic lymphoma; the remaining eight cases were B-cell lymphomas. Seven of the latter cases were high-grade B-cell lymphomas and one was a true follicular lymphoma. None of our cases showed the features of lymphoma arising in mucosa-associated lymphoid tissue.

Primary non-Hodgkin's lymphomas of the female breast

The charts of 35 women with primary malignant non-Hodgkin's lymphomas (NHL) of the breast were retrieved from the files of the Istituto Nazionale Tumori, Milan, over a 30-year period (1957 to 1986). These cases represented 0.1% of the more than 25,000 primary malignant tumors of the breast treated during the same period. The median age of these patients was 57 years (range, 28 to 81 years). In most cases, the clinical diagnosis was carcinoma. The tumors were either Stage IE(48%) or IIE(52%) at presentation, and only two patients had B symptoms. The right breast was involved in 17 patients, the left breast in 14, and both breasts in two. According to the updated Kiel classification and the Working Formulation (WF) for Clinical Usage, three cases were lymphoplasmacytoid (immunocytoma) NHL (WF, A); three, centroblastic-centrocytic, follicular NHL (WF, B); four, centroblastic-centrocytic, diffuse NHL (WF, F); 17 centroblastic NHL (WF, G); three immunoblastic NHL (WF, H); two B-lymphoblastic NHL (WF, I); and one, a Burkitt-like NHL (WF, J). Treatment consisted either of a combination of surgery, radiation therapy, and chemotherapy or radiation therapy and chemotherapy. The follow-up period for 32 patients ranged from 6 to 161 months (mean, 45 months); 17 patients died of their disease. The prognosis appeared to be related to the histologic type and stage of the disease. Median survival periods were 63, 52, 42, and 47 months for centroblastic-centrocytic follicular, centroblastic-centrocytic diffuse, centroblastic, and immunoblastic NHL, respectively. The overall 5-year survival rate was 43%; the 5-year survival rate and the probability of freedom from progression at 5 years were, respectively, 61% and 50% for Stage I and 27% and 26% for Stage II disease.

Primary breast lymphoma

Primary breast lymphoma (PBL) is a rare tumor of the breast. Three cases of PBL are being described. All three cases achieved remission following biopsy, chemotherapy, and/or radiotherapy. The literature is extensively reviewed with emphasis on true incidence of PBL and survival rates.

Fatty acid modulation of antiestrogen action and antiestrogen-binding protein in cultured lymphoid cells

Nonsteroidal antiestrogens reversibly and specifically inhibited the proliferation of two estrogen receptor-negative lymphoid cell lines (EL4 and Raji) in a dose-dependent manner. [3H]Thymidine incorporation of concanavalin A-stimulated primary splenocytes was also inhibited by 10(-6) M clomiphene (1-[4-(2-diethylaminoethoxy)phenyl]-1,2-diphenyl-2-chloroethylene). The antiproliferative effect could be prevented by the simultaneous presence in the growth medium of 10(-5) M linoleic acid or 10(-5) M arachidonic acid but not by 10(-6) M estradiol. Both lymphoid cell lines had high affinity antiestrogen-binding sites whose affinity could be altered by conditions of growth. Growth of EL4 cells in RPMI 1640 medium supplemented with charcoal-pretreated 5% fetal calf serum (charcoal-stripped medium) resulted in significantly higher affinity (Kd 0.54 nM +/- 0.11 nM; n = 6) than growth in medium supplemented with untreated serum (complete medium) (Kd = 1.68 nM +/- 0.48 nM; n = 6) (p less than 0.001). This change in affinity was partly due to removal of fatty acids from the growth medium by charcoal pretreatment, since addition of 10(-5) M linoleic acid or 10(-5) M gamma-linolenic to charcoal-stripped medium decreased the affinity of the antiestrogen-binding protein. In contrast, growth in 10(-5) M stearic acid or 10(-5) M oleic acid did not significantly alter the affinity of the antiestrogen-binding protein, whereas 10(-5) M palmitic acid significantly increased its affinity. The same fatty acids were also tested for their intrinsic effects on EL4 cell proliferation. Oleic, linoleic and gamma-linolenic acids were growth stimulatory while stearic and palmitic acids were not. Thus linoleic and gamma-linolenic acids whose presence in the growth medium was associated with decreased affinity of [3H]tamoxifen (1-[4-(2-dimethylaminoethoxy)phenyl]-1,2-diphenylbut-1(Z)-ene) binding to the intracellular antiestrogen-binding protein were also growth stimulatory. Unsaturated fatty acids have previously been shown to inhibit binding of [3H]tamoxifen to the antiestrogen-binding protein in a cell-free system. The present observations demonstrate that unsaturated fatty acids also modify the affinity of the antiestrogen-binding protein in intact cells.