Impact of Expert Pathologic Review of Lymphoma Diagnosis: Study of Patients From the French Lymphopath Network.

Purpose To prospectively assess the clinical impact of expert review of lymphoma diagnosis in France. Materials and Methods From January 2010 to December 2013, 42,145 samples from patients with newly diagnosed or suspected lymphomas were reviewed, according to the 2008 WHO classification, in real time by experts through the Lymphopath Network. Changes in diagnosis between referral and expert review were classified as major or minor according to their potential impact on patient care. Results The 42,145 reviewed samples comprised 36,920 newly diagnosed mature lymphomas, 321 precursor lymphoid neoplasms, 314 myeloid disorders, and 200 nonhematopoietic neoplasms, with 4,390 benign lesions. There were 4,352 cutaneous and 32,568 noncutaneous lymphomas. The most common mature noncutaneous lymphomas were diffuse large B-cell lymphomas (32.4%), follicular lymphomas (15.3%), classic Hodgkin lymphomas (13%), peripheral T-cell lymphomas (6.3%) of which angioimmunoblastic T-cell lymphomas (2.3%) were the most frequent, and mucosa-associated lymphoid tissue lymphomas (5.8%). A diagnostic change between referral and expert review occurred in 19.7% of patients, with an estimated impact on patient care for 17.4% of patients. This rate was significantly higher for patients sent with a provisional diagnosis seeking expert second opinion (37.8%) than for patients sent with a formal diagnosis (3.7%). The most frequent discrepancies were misclassifications in lymphoma subtype (41.3%), with 12.3% being misclassifications among small B-cell lymphoma entities. Fewer than 2% of changes were between benign and malignant lymphoid conditions. Minor changes (2.3%) mostly consisted of follicular lymphoma misgrading and diffuse large B-cell lymphoma subtype misclassification. Conclusion To our knowledge, this study provides the largest ever description of the distribution of lymphoma entities in a western country and highlights how expert review significantly contributes to a precise lymphoma diagnosis and optimal clinical management in a proportion of patients.

Risk assessment of second primary cancer according to histological subtype of non-Hodgkin lymphoma.

Non-Hodgkin lymphoma (NHL) represents a heterogeneous group of diseases that are known to carry a considerable risk of second primary cancer (SPC). However, little attention has been paid to SPC risk assessment according to NHL subtypes. Data from 10 French population-based cancer registries were used to establish a cohort of 7546 patients with a first diagnosis of NHL (eight subtypes) between 1989 and 2004. Standardized incidence ratios (SIRs) of metachronous SPC were estimated. Among the 7546 patients diagnosed with a NHL, the overall SPC risk was 25% higher than that in the reference population (SIR = 1.25, 95% confidence interval 1.15-1.36). In univariate analysis, the SPC risk differed by lymphoma subtype. Interestingly, multivariate analysis showed that SPC risk did not differ significantly across NHL subtypes after adjustment for the other covariates (p = 0.786). Patients with NHL have an increased risk of SPC that is not influenced by the histological NHL subtype.

The heterogeneity of changes in incidence and survival among lymphoid malignancies in a 30-year French population-based registry.

Our specialized population-based registry has allowed us to explore changes in incidence and survival by subtype over the last 30 years. Between 1980 and 2009, 4790 cases of lymphoid malignancies were registered using the International Classification of Diseases for Oncology. The incidence rate of lymphoid malignancies was 20.5 per 100,000 inhabitants per year, and ranged from 0.1 to 4 according to subtype. Five-year net survival was 65%, and ranged from 41% to 93% according to subtype. We observed an increase in 5-year net survival between the periods 1980-1989 and 2000-2009 (58% vs. 70%). This was observed in most but not all subtypes. Our long-standing population-based registry allowed us to measure differences in trends according to the subtype of lymphoid malignancy. Incidence rates steadily increased in quite frequent entities, and poor survival probability for most entities indicates that they should be the next objective in therapeutic research programs.

Trends in excess mortality in follicular lymphoma at a population level.

BACKGROUND: Since the 1990s and since the development of humanised monoclonal antibodies in 1998, the treatment of non-Hodgkin lymphoma has undergone profound changes. Follicular lymphoma (FL) was the first to benefit from this treatment, and several clinical trials have shown a significant improvement in overall survival, but little information is available at a population level. OBJECTIVE: Our objective was to estimate changes in FL-specific mortality at a population level, with an appropriate methodology. METHODS: Two French retrospective population-based studies on FL were conducted, one from 1995 to 2004, in 1477 patients, and one from 1995 to 2010, in 451 patients. Trends in excess mortality rates (EMRs) according to age, sex, Ann Arbor stage and year of diagnosis were evaluated using the flexible model of Remontet et al. RESULTS: Trends in the EMR differed according to age at diagnosis and was higher in advanced stage (III, IV) in patients older than 65 yr. The EMR decreased linearly from 1995 to 2010. This decrease was more marked for advanced stages. CONCLUSION: FL-specific mortality decreased over the years of diagnosis, and the difference according to the lymphoma stage diminished in more recent years. However, progress in the management of FL was not able to erase age-related differences.