Don Wilson

Outcome prediction by extranodal involvement, IPI, R-IPI, and NCCN-IPI in the PET/CT and rituximab era: A Danish–Canadian study of 443 patients with diffuse-large B-cell lymphoma

18F‐fluorodeoxyglucose PET/CT (PET/CT) is the current state‐of‐the‐art in the staging of diffuse large B‐cell lymphoma (DLBCL) and has a high sensitivity for extranodal involvement. Therefore, reassessment of extranodal involvement and the current prognostic indices in the PET/CT era is warranted. We screened patients with newly diagnosed DLBCL seen at the academic centers of Aalborg, Copenhagen, and British Columbia for eligibility. Patients that had been staged with PET/CT and treated with R‐CHOP(‐like) 1st line treatment were retrospectively included. In total 443 patients met the inclusion criteria. With a median follow‐up of 2.4 years, the 3‐year overall (OS) and progression‐free survival (PFS) were 73% and 69%, respectively. The Ann Arbor classification had no prognostic impact in itself with the exception of stage IV disease (HR 2.14 for PFS, P<0.01). Extranodal involvement was associated with a worse outcome in general, and in particular for patients with involvement of >2 extranodal sites, including HR 7.81 (P < 0.001) for PFS for >3 sites. Bone/bone marrow involvement was the most commonly involved extranodal site identified by PET/CT (29%) and was associated with an inferior PFS and OS. The IPI, R‐IPI, and NCCN‐IPI were predictive of PFS and OS, and the two latter could identify a very good prognostic subgroup with 3‐year PFS and OS of 100%. PET/CT‐ascertained extranodal involvement in DLBCL is common and involvement of >2 extranodal sites is associated with a dismal outcome. The IPI, R‐IPI, and NCCN‐IPI predict outcome with high accuracy. Am. J. Hematol. 90:1041–1046, 2015.

High-Grade Glioma Radiation Therapy Target Volumes and Patterns of Failure Obtained From Magnetic Resonance Imaging and 18F-FDOPA Positron Emission Tomography Delineations From Multiple Observers

PURPOSE The objective of this study was to compare recurrent tumor locations after radiation therapy with pretreatment delineations of high-grade gliomas from magnetic resonance imaging (MRI) and 3,4-dihydroxy-6-[(18)F]fluoro-L-phenylalanine ((18)F-FDOPA) positron emission tomography (PET) using contours delineated by multiple observers. METHODS AND MATERIALS Nineteen patients with newly diagnosed high-grade gliomas underwent computed tomography (CT), gadolinium contrast-enhanced MRI, and (18)F-FDOPA PET/CT. The image sets (CT, MRI, and PET/CT) were registered, and 5 observers contoured gross tumor volumes (GTVs) using MRI and PET. Consensus contours were obtained by simultaneous truth and performance level estimation (STAPLE). Interobserver variability was quantified by the percentage of volume overlap. Recurrent tumor locations after radiation therapy were contoured by each observer using CT or MRI. Consensus recurrence contours were obtained with STAPLE. RESULTS The mean interobserver volume overlap for PET GTVs (42% ± 22%) and MRI GTVs (41% ± 22%) was not significantly different (P=.67). The mean consensus volume was significantly larger for PET GTVs (58.6 ± 52.4 cm(3)) than for MRI GTVs (30.8 ± 26.0 cm(3), P=.003). More than 95% of the consensus recurrence volume was within the 95% isodose surface for 11 of 12 (92%) cases with recurrent tumor imaging. Ten (91%) of these cases extended beyond the PET GTV, and 9 (82%) were contained within a 2-cm margin on the MRI GTV. One recurrence (8%) was located outside the 95% isodose surface. CONCLUSIONS High-grade glioma contours obtained with (18)F-FDOPA PET had similar interobserver agreement to volumes obtained with MRI. Although PET-based consensus target volumes were larger than MRI-based volumes, treatment planning using PET-based volumes may not have yielded better treatment outcomes, given that all but 1 recurrence extended beyond the PET GTV and most were contained by a 2-cm margin on the MRI GTV.

The value of routine bone marrow biopsy in patients with diffuse large B-cell lymphoma staged with PET/CT: a Danish-Canadian study

BACKGROUND The added diagnostic and prognostic value of routine bone marrow biopsy (BMB) in patients with diffuse large B-cell lymphoma (DLBCL) undergoing positron emission tomography combined with computed tomography (PET/CT) staging is controversial. PATIENTS AND METHODS Patients with newly diagnosed DLBCL who underwent both staging PET/CT and BMB were retrospectively identified in British Columbia, Aalborg, and Copenhagen. Original written PET/CT and pathology reports were retrospectively reviewed to determine Ann Arbor stage and outcomes, with and without the contribution of BMB. RESULTS A total of 530 patients were identified: 146 (28%) had focal bone marrow (BM) lesions on PET/CT and 87 (16%) had positive BMB. Fifty-two of 146 patients (36%) with positive PET/CT had a positive BMB [39 DLBCL, 13 indolent non-Hodgkin lymphoma (iNHL)], while 35 of 384 patients (9%) with negative PET/CT had positive BMB (12 DLBCL, 23 iNHL). BMB upstaged 12/209 (6%) of stage I/II patients to stage IV, although this was the case for only 3 (1%) patients with DLBCL in the BMB. PET/CT identified BM involvement by BMB with sensitivity 60%, specificity 79%, positive predictive value 36%, and negative predictive value 91%. Concordant histological involvement of the BM by DLBCL was associated with worse overall survival and progression-free survival than discordant or no involvement in univariate and multivariate analyses. CONCLUSIONS In patients with DLBCL, staging PET/CT can miss BM involvement with concordant DLBCL (less common) or discordant iNHL (more common). Routine BMB does not add relevant diagnostic or prognostic value over PET/CT alone in the majority of patients with DLBCL.

Impact of F-18 Fluorodeoxyglucose Positron Emission Tomography–Computed Tomography on Oncologic Patient Management: First 2 Years' Experience at a Single Canadian Cancer Center

Purpose The purpose of this study was to assess the influence of positron emission tomography–computed tomography (PET-CT) results on patient management from a single Canadian oncology center during its first 2 years of operation. Methods A total of 3,779 consecutive patients, 18 years of age and older, who were referred for PET-CT imaging at the British Columbia Cancer Agency between July 1, 2005 and June 30, 2007, were included in this analysis. Results were tabulated from a standard questionnaire, which was given to referring physicians following completion of their patients PET-CT study. Results From July 1, 2005 to June 30, 2007, 3,779 consecutive fluoro-2-deoxyglucose PET-CT examinations were performed in patients aged 18 years or older. A total of 3,429 referring-physician surveys (90.7%) were returned. The results of the PET-CT study resulted in a change in treatment decision in 49.8% of the studies and resulted in improved decision making in 83.2% of the studies. Conclusion This series demonstrated that the results from PET-CT studies performed at a single Canadian oncology center during the first 2 years of its operation altered patient management in 50% of cases and resulted in improved decision making in the majority of cases.

Interim PET-directed therapy in limited stage Hodgkin lymphoma initially treated with ABVD

Limited-stage Hodgkin lymphoma (HL) is a highly curable malignancy when treated with combination chemotherapy with or without radiotherapy (RT). The majority of patients experience long-term survival but remain at risk for late treatment-related complications, particularly those related to RT, including second malignancies and cardiovascular disease. In an attempt to balance the risks and benefits of the use of RT for patients with limited stage HL, especially potential long-term toxicity, the Lymphoma Tumor Group at BC Cancer introduced a treatment policy change in July 2005 recommending an approach based on 18F-fluorodeoxyglucose (FDG) positron emission tomography after two cycles of chemotherapy (PET2). Patients achieving a complete response (CR) after two cycles of ABVD, defined as a negative PET2, were recommended to receive two additional cycles of ABVD without RT. Patients with a positive PET2 were switched to involved nodal radiotherapy (INRT), with the rationale that using non-cross-resistant RT has the potential to eradicate possible residual disease implied by persistent PET positivity despite ABVD. Patients age >15 years diagnosed with limited stage classical HL between July 2005 and April 2016 were identified in the BC Cancer Lymphoid Cancer Database. Limited stage was defined as Ann Arbor stage IA, IB or IIA, with or without associated contiguous extranodal extension, and with the largest single mass measuring <10 cm. Patients were not otherwise categorized into favorable or unfavorable subgroups because erythrocyte sedimentation rate is not routinely tested at our institution. Diagnostic biopsies were reviewed by an expert BC Cancer hematopathologist and classified according to the World Health Organization Classification. PET2 scans were performed and reported centrally at the BC Cancer – Vancouver Cancer Centre. Before January 2014, PET scans were interpreted based on the International Harmonization Project to categorize PET2 results as negative, indeterminate, or positive to guide therapy. Those with an indeterminate score were recommended to be treated as PET positive and receive INRT. This was replaced by the 5-point Deauville (D) scale in January 2014 where D1 and D2 were considered PET negative (i.e., a CR), D3-5 were considered PET positive, and cases with new uptake not felt to represent lymphoma were assigned a ‘X’ score. Importantly, both systems considered the PET2 as positive if the maximum uptake was greater than the mediastinum and, therefore, requiring RT (i.e., including those with an indeterminate score). A total of 286 prospectively diagnosed patients with stage IA, IB, or IIA HL diagnosed between 2005 – 2016 were identified. Of these, 47 were excluded for the following reasons: 37 nodular lymphocyte predominant HL, 9 illness/frailty at baseline precluding a PET-driven curative approach, and 1 in whom PET2 was not performed. Clinical characteristics of the 239 patients included in the current analysis are listed in Table 1. Patients were intended to receive two cycles of ABVD with curative intent, although 4 patients received a third cycle due to difficulty scheduling PET scans and 5 patients received ABVD-based alternating or hybrid regimens, which were considered to be equivalent to ABVD, by physician choice. Following two cycles of initial chemotherapy, PET2 was negative in 210 (88%) patients, and positive in 29 (12%). The IHP response criteria were applied in 173 (72%) patients while Deauville criteria were applied to the remaining 66 (28%) patients, with no difference in the proportion of patients achieving a PET2 negative scan (88% vs. 86%, respectively, P=0.660). Among the 210 PET2-negative patients planned for treatment with 2 additional cycles of ABVD, the majority (n=206, 98%) received 2 additional cycles of ABVD, although 4 of the 206 were not able to complete all 4 cycles (total 2 cycles [n=1], 3 cycles [n=3]) due to patient refusal (n=2) or chemotherapy toxicity (n=2, both with severe fatigue), and did not receive further therapy. The remaining 4 PET2-negative patients were immediately switched to INRT after the two initial cycles of ABVD by physician/patient preference due to perceived intolerance to chemotherapy. All 29 PET2-positive patients (median SUVmax 2.8 [range 1.5 – 26]) received consolidative INRT. Of these

The standard, revised and simplified international prognostic index reliably predict outcome in patients with PET/CT-staged DLBCL treated with R-chop

151 Table CD3 P ≥ 50 CD4 P ≥ 50 CD8 P ≥ 50 CD3/B-cell P ≥ 50 CD4/CD8 P ≥ 50 CD4 TFH/CD4 + P ≥ 75 Age (%) <60 years 39 34 29 21 55 21 ≥60 years 59 56 57 43 43 39 Histological grade (%) 1–2 45 43 35 27 58 29 3 89 67 89 67 0 11 Bulky disease (%) No 57 53 46 60 46 23 Yes 22 17 33 11 56 29 Extranodal (%) ≤1 58 52 51 58 47 23 >1 21 21 21 26 53 29 Leukemic phase (%) No 56 50 48 32 60 22 Yes 10 10 10 0 46 25 182 Poster Presentations resistance. Immune cells in the lymphoma tumour microenvironment have been implicated in disease progression (Dave et al., NEJM 2004) and may play a role in transformation. We recently discovered that expression of the inhibitory receptor PD-1 was associated with suppressed cytokine signalling in FL tumour-infiltrating T cells (Myklebust et al., Blood 2013). Furthermore, it has been suggested that PD-1 int cells are the truly exhausted T cells and that PD-1 high cells are normal T follicular helper cells (TFH) (Yong et al., Blood Cancer J 2015). Antibody immunotherapy targeting PD-1 has shown significant promise in aggressive malignancies (Topalian et al., NEJM 2012), suggesting that exhausted T cells can regain functionality, including anti-tumour effects. Methods: Three mass cytometry (CyTOF) panels were designed to detect 30 markers per cell and used to characterize FL tumour biopsies (n = 9) and human tonsils. In the first panel, inhibitory and co-stimulatory receptors were quantified across 5 major T-cell subsets and maturation stages (Nicholas and Greenplate et al., manuscript in preparation). In the second panel, key surface markers were combined with antibodies to detect 12 phosphoproteins to correlate signalling responses with inhibitory receptor profiles. The last panel was designed to characterize healthy and malignant B cells. The dimensionality-reduction tool viSNE was used to analyse the high-dimensional mass cytometry data. Fluorescent flow panels were used in parallel to measure 9 inhibitory receptors in selected T-cell subsets. Results: viSNE analysis of 23 surface markers revealed a high degree of phenotypic similarity between T cells infiltrating FL and T cells in tonsils. In contrast, viSNE characterized the significant phenotypic differences between malignant B cells and healthy B cells within the same tumour. PD1 + T cells from FL samples displayed reduced cytokine signalling compared to PD1 cells, confirming previous results. TFH cells were identified as CXCR5 hi ICOS + CD4 memory T cells. Among the ICOS + cells in tonsils, a distinct CXCR5 population was identified with intermediate PD1 expression, suggesting an exhausted phenotype. These cells expressed less TIGIT, BTLA and LAIR1 than TFH but contained a subpopulation of TIM3 + cells that was not seen within the TFH population. Conclusions: Striking similarities in phenotype and signalling response of the T cells infiltrating FL tumours and T cells from healthy tonsil observed by mass cytometry suggest active immune responses in these tissues. These results provide further support for characterizing relationships between receptor signalling and T cell function and for researching into combination immunotherapies for FL focused on modulating adaptive immune responses. 151 T-CELL SUBPOPULATIONS QUANTIFIED BY FLOW CYTOMETRY IN LYMPH NODE CELL SUSPENSIONS IDENTIFY A GROUP OF PATIENTS WITH FOLLICULAR LYMPHOMA WITH FAVORABLE OUTCOME L. Magnano 1 , J. Carreras 2 , A. Martinez 2 , A. Martinez-Trillos 1 , J. Rovira 1 , I. Dlouhy 1 , E. Gine 1 , T. Bauman 1 , O. Balague 2 , E. Campo 2 , N. Villamor 3 , A. López-Guillermo 1 . 1 Hematología, Hospital Clinic de Barcelona, Barcelona, Spain, 2 Pathology Department, Hospital Clinic de Barcelona, Barcelona, Spain, 3 Hematopathology Unit, Hospital Clinic de Barcelona, Barcelona, Spain. Introduction: Tumour microenvironment plays an important role in the behaviour of follicular lymphoma (FL). By gene expression and immunohistochemistry, an increase in macrophages has been associated with poor outcome, while an increase in T cells is associated with good prognosis. The aim of the study was to explore the prognostic impact of subpopulations of T cells using flow cytometry and to identify different groups of risk in FL patients. Methods: Seventy-five patients (36 men/39 women, median age 60 years) diagnosed of FL (grades 1–2, 87%; grade 3, 13%) between 1984 and 2009 (median follow-up of 6.5 years) with sample at diagnosis were included in the present study. In 41 cases, T-cell staining were semiquantitatively analysed by immunohistochemical (IHC), including their distribution (intra, inter or perifollicular). T-cell populations from lymph node were quantified by multiparametric flow cytometry in cell suspensions in all cases. The percentage of B-cells, CD3 + , CD4 + , CD8 + , CD57 + , CD4TFH cells (double staining CD4 + CD57 + ), as well as the ratio T/B-cells, CD3 + /CD4 + , CD3 + /CD8 + , CD4 + /CD8 + and CD4TFH/CD4 + were analysed and correlated with initial features and outcome. Copyright

WE‐G‐214‐08: Interobserver Volume Variations in the Target Delineation of High‐Grade Gliomas Using Magnetic Resonance Imaging and 18F‐FDOPA Positron Emission Tomography

Purpose: To quantify interobserver variations in the delineation of high‐grade gliomas for magnetic resonance imaging(MRI) with gadolinium (Gd) contrast and positron emission tomography(PET) with 3,4‐dihydroxy‐6‐ ,18F‐fluoro‐L‐phenylalanine (,18F‐FDOPA) imaging modalities. Methods: Twenty patients with histologically confirmed high‐grade gliomas underwent radiotherapytreatment planning with computed tomography, Gd‐enhanced MRI and ,18F‐FDOPA PET. The images were fused and two trained observers delineated the Gd enhancement and ,18F‐FDOPA uptake. The MRI‐based gross tumor volume (GTV) was defined as the volume of Gd enhancement excluding the surgical cavity. The PET‐based GTV was defined as the union of the ,18F‐FDOPA uptake and Gd enhancement excluding the surgical cavity. For each GTV, a clinical target volume (CTV) was defined as the union of the GTV and the surgical cavity, plus a 2‐cm three dimensional (3D) margin. A planning target volume (PTV) was defined as a 0.5‐cm 3D margin on the CTV. Interobserver and intermodality variability of the GTV, CTV and PTV were quantified by differences in the volume and percent volume overlap (PVO) of the structures. Results: The MRI‐based and PET‐based GTV volumes delineated by the second observer were on average 0.65 and 0.98 times the volumes delineated by the first observer. The root mean square error (RMSE) of the linear regression of the interobserver volumes was 10.7 cm,3 and 16.0 cm,3 for MRI‐based and PET‐based volumes. The interobserver GTV PVO for MRI‐based and PET‐based delineations was similar (49.6% vs. 59.1%, p=0.132). PET‐based GTV volumes were 1.6 times larger than MRI‐based volumes, with a RMSE of 27.6 cm,3. The mean intermodalily GTV PVO was 41.6%. Conclusions: There was less interobserver variability for GTV volumes delineated with combined MRI and ,18F‐FDOPA PET compared to volumes delineated with MRI only. GTV volumes delineated with both MRI and PET were 1.6 times larger than volumes delineated using only MRI.