Incidence, risk factors and outcome of histological transformation in follicular lymphoma

Abstract

SummaryHistological transformation (HT) into diffuse large B-cell lymphoma (DLBCL) was documented in 37 of the 281 (13%; 95% CI, 9-18) follicular lymphoma (FL) patients treated at our institute from 1979 to 2007. HT occurred at a median of 2·75 years from initial FL diagnosis and HT rate was 15% at 10 years and 26% at 14 years, with a plateau from that point onward. Patients with bulky or extranodal disease, or those diagnosed before 1990 had a significantly higher risk of HT. When initial treatment strategies were taken into account, a reduced HT risk was seen in the patients initially managed with a 'watch and wait' policy, while the risk appeared significantly increased in the small subset of 18 patients initially managed with rituximab plus chemotherapy (P = 0·0005). HT was associated with a significantly shorter cause-specific survival (P = 0·0002).

Rates and Outcomes of Follicular Lymphoma Transformation in the Immunochemotherapy Era: A Report From the University of Iowa/Mayo Clinic Specialized Program of Research Excellence Molecular Epidemiology Resource

“…18 Survival after transformation was also higher (44% 3-year OS) for the British Columbia patients who transformed after limited-stage FL, 85% of whom were chemotherapy-naive at transformation. 20 Our observation of a median survival of nearly 5 years deserves close scrutiny, but extends the observations that anthracycline-naive patients do relatively well as do patients diagnosed in the era of immunotherapy.…”

“…17 Indeed, one recent series of patients diagnosed from 1979 to 2007 found a significantly higher risk of transformation in patients diagnosed before 1990. 18 Similarly, treatment options for management of transformed lymphoma have expanded over this time frame.…”

“…27,28 Other recent series with lower rates of transformation include a Swiss study of patients from 1979 to 2007 with a 5-year transformation rate of 13% but limited the definition of transformation to biopsy proven, and a BCCA report focusing on patients with limited presenting stage treated with radiotherapy with a 5-year risk of transformation of 9%. 18,20 The observation that transformation rates and death without transformation at 5 years are similar at approximately 10% will be useful for calculating power in the design of future clinical trials of newly diagnosed FL.…”

Follicular Lymphoma: The Role of the Tumor Microenvironment in Prognosis

“…7 FL is a low grade lymphoma with variable clinical course; in some patients, the disease is indolent and slowly progressive over a period of many years, with waxing and waning lymphadenopathy, whereas in others the disease progresses rapidly, often with transformation to aggressive lymphoma and early death. 8 Despite advances in the treatment of FL, most FL patients remain incurable and, at 5 years approximately 11% 9 to 13% of cases, 10 and at 10 years 15% 10 to 28% 11 of cases will transform to an aggressive phenotype, typically diffuse large B-cell lymphoma (DLBCL). Management strategies include watch and wait, immunochemotherapy, and new targeted treatment options.…”

The miR-17-92 microRNA cluster: a novel diagnostic tool in large B-cell malignancies

“…27,28 Moreover, in the presence of diffuse areas (425%) of blastic cells in a grade 3 FL, the cases have been proposed to be referred as a full-blown DLBCL. 27,28,35 Also by the molecular point of view, DLBCL includes genetic and molecular alterations often shared with high-grade FL. Both these lymphomas generally express B-cell antigens (CD-19, CD-20, and CD-79a), surface/cytoplasmic immunoglobulin, and (in various proportions) CD10, BCL-2 protein, and BCL-6 protein.…”