Value of follow-up procedures in patients with large-cell lymphoma who achieve a complete remission

OUP accepted manuscript

Circulating biomarkers have emerged as valuable surrogates for evaluating disease states in solid malignancies. Their relative ease of access and rapid turnover has bolstered clinical applications in monitoring treatment efficacy and cancer progression. In this review, the roles of various circulating biomarkers in monitoring treatment response are described. Non-specific markers of disease burden, tumor markers (eg CA 125, CEA, PSA, etc.), circulating tumor cells, nucleic acids, exosomes, and metabolomic arrays are highlighted. Specifically, the discovery of each of these markers is reviewed, with examples illustrating their use in influencing treatment decisions, and barriers to their application noted where these exist. Finally, opportunities for future work using these circulating biomarkers are discussed.

Limiting surveillance imaging for patients with lymphoma in remission: a mixed methods study leading to a Choosing Wisely recommendation

BACKGROUND

Under the 'Choosing Wisely' (CW) framework, professional organisations internationally have advocated limiting imaging for asymptomatic patients following curative cancer therapy, based on limited value and high cost. F18-fluorodeoxyglucose (FDG) positron emission tomography-CT (PET/CT) was widely adopted locally for surveillance lymphoma imaging after 2004.

OBJECTIVES

Prior to ratification of a local CW recommendation to limit surveillance imaging in lymphoma, we aimed to assess: (A) performance characteristics of surveillance FDG-PET/CT; (B) rates, clinical consequences and costs of false positives (FP); and (C) patients and professionals' attitudes towards overuse.

METHODS

Mixed methods (quantitative and qualitative) study. We analysed surveillance FDG-PET/CT results of two patient cohorts (n1=215 Hodgkin lymphoma and non-Hodgkin lymphoma; n2=203 Hodgkin lymphoma only). FPs were defined by negative biopsy or clinical follow-up. We held focus group discussions and in-depth interviews eliciting attitudes of 26 patients and 11 clinicians, respectively.

RESULTS

FPs were observed in 25.1% (95% CI 20.5 to 30.5) per scan-cohort 1, and 41.7% (95% CI 37.9 to 45.6) per patient-cohort 2, engendering frequent additional testing. Specific characteristics and location of findings altered the FP rate. The estimated cost per relapse detected was $50 000 (cohort 2). Patients sought reassurance via surveillance imaging, which they considered highly accurate, yet stressful. Aware of radiation risks, they were largely unconcerned about consequences of FPs. Confidence in the treating physicians was an important factor in patients' acceptance of forgoing imaging. Clinicians, frequently under patient pressure to order imaging, generally believed that it did not affect prognosis (with important exceptions), welcomed professional guidelines, but rejected regulatory restrictions on its use.

CONCLUSION

Acceptance of CW recommendations to limit overuse may be enhanced by quantitative data on consequences and costs of surveillance imaging, supplemented by qualitative data on patient and physician attitudes.

FDG-PET/CT in the management of lymphomas: current status and future directions

FDG-PET/CT is the current state-of-the-art imaging in lymphoma and plays a central role in treatment decisions. At diagnosis, accurate staging is crucial for appropriate therapy selection: FDG-PET/CT can identify areas of lymphoma missed by CT alone and avoid under-treatment of patients with advanced disease stage who would have been misclassified as having limited stage disease by CT. Particularly in Hodgkin lymphoma, positive interim FDG-PET/CT scans are adversely prognostic for clinical outcomes and can inform PET-adapted treatment strategies, but such data are less consistent in diffuse large B-cell lymphoma. The use of quantitative FDG-PET/CT metrics using metabolic tumour volume, possibly in combination with other biomarkers, may better define prognostic subgroups and thus facilitate better treatment selection. After chemotherapy, FDG-PET/CT response is predictive of outcome and may identify a subgroup who benefit from consolidative radiotherapy. Novel therapies, in particular immunotherapies, exhibit different response patterns than conventional chemotherapy, which has led to modified response criteria that take into account the risk of transient pseudo-progression. In relapsed lymphoma, FDG-PET/CT after second-line therapy and prior to high-dose therapy is also strongly associated with outcome and may be used to guide intensity of salvage therapy in relapsed Hodgkin lymphoma. Currently, FDG-PET/CT has no role in the routine follow-up after complete metabolic response to therapy, but it remains a powerful tool for excluding relapse if patients develop clinical features suggestive of disease relapse. In conclusion, FDG-PET/CT plays major roles in the various phases of management of lymphoma and constitutes a step towards the pursuit of personalized treatment.

Routine blood investigations have limited utility in surveillance of aggressive lymphoma in asymptomatic patients in complete remission

BACKGROUND

Patients with aggressive lymphoma achieving complete remission (CR) after first-line combination chemotherapy undergo regular surveillance to detect relapse. Current international guidelines recommend routine follow-up blood tests in this context, but evidence supporting this practice is limited.

METHODS

We conducted a multi-centre retrospective analysis of all patients diagnosed with aggressive lymphoma treated with curative-intent chemotherapy who achieved CR for at least 3 months between 2000 and 2015. An abnormal blood test was defined as any new and unexplained abnormality for full blood examination, lactate dehydrogenase or erythrocyte sedimentation rate.

RESULTS

Three hundred and forty-six patients attended a total of 3084 outpatient visits; blood tests were performed at 90% of these appointments. Fifty-six (16%) patients relapsed. Routine laboratory testing detected relapse in only three patients (5% of relapses); in the remaining patients, relapse was suspected clinically (80%) or detected by imaging (15%). The sensitivity of all blood tests was 42% and the positive predictive value was 9%. No significant difference in survival was shown in patients who underwent a routine blood test within 3 months prior to relapse versus those who did not (p = 0.88).

CONCLUSIONS

Routine blood tests demonstrate unacceptably poor performance characteristics, have no impact on survival and thus have limited value in the detection of relapse in routine surveillance.

Gallium-67 as a Tumor-seeking Agent in Lymphomas - a Review

Background

At present 67Ga can be considered one of the most widely used viability radiotracers. There is general consensus in the literature that 67Ga has the highest clinical value in the management of lymphoma patients.

Methods

We critically discuss the role of gallium scintigraphy in lymphoma patients on the basis of the experience of the Nuclear Medicine Division at the National Cancer Institute of Milan.

Results and Conclusions

The sensitivity of gallium scan is very high (80-90%) in the staging and follow-up of Hodgkin's disease, and the method is also of great importance in the follow-up of lymphoma patients. We recommend scintigraphy to study the residual mediastinal mass after treatment. Our experiences during the follow-up of 189 lymphoma patients clearly showed the superior performance of gallium scan compared to MRI in the study of the mediastinal region after treatment. Sensitivity and specificity were both very high (90% and 96.9% vs 88.7% and 89.2%, respectively). Gallium scintigraphy can also be used to study the disease-free interval, posttreatment survival, early signs of recurrence and treatment response times. Comparison of the survival curves of 33 patients with diffuse large cell Non-Hodgkin's lymphoma examined at the National Cancer Institute showed a statistically significant difference (logrank test, P=0.0125) between patients with positive and those with negative gallium scan after 4-6 cycles of chemotherapy.

Are We Choosing Wisely in Lymphoma? Excessive Use of Surveillance CT Imaging in Patients With Diffuse Large B-cell Lymphoma (DLBCL) in Long-term Remission

INTRODUCTION

The use of surveillance computed tomography (CT) imaging in patients with diffuse large B-cell lymphoma in remission is neither effective nor cost-effective. The American Society of Hematology Choosing Wisely (CW) campaign, in particular, emphasizes the lack of benefit beyond 2 years of completion of therapy. We sought to describe the real-world practice of surveillance imaging.

PATIENTS AND METHODS

We used population-based health system administrative databases from Ontario, Canada. We studied a cohort of all adult patients ≥ 18 years with diffuse large B-cell lymphoma who received rituximab (R) with CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) between 2004 and 2012. We defined an index date of 2 years after the last dose of RCHOP as the time frame beyond which surveillance imaging would be inappropriate. The cumulative incidence of receiving CT scans after the index date represented the primary outcome of interest.

RESULTS

The cohort consisted of 2401 patients treated with RCHOP during the study period. The cumulative incidence reached 52.5% (range, 50.4%-54.6%) by 3 years of follow-up. On multivariable analysis, patients with more comorbidities and within certain geographic regions within the province were noted to have increased CT scanning. The cumulative incidence appeared to decrease over the study follow-up period (from 62.4% in 2006 to 48.0% in 2014; P < .001).

CONCLUSION

During a timeframe in which surveillance imaging is deemed unnecessary by the CW campaign, the practice remains excessive. Regional variations in CT scanning suggest that local practice patterns can be targeted to reduce imaging. A recent decline in scanning may reflect a broadening appreciation for the evidence against surveillance or uptake of the CW campaign.

Circulating Tumor DNA to Monitor Therapy for Aggressive B-Cell Lymphomas

OPINION STATEMENT

The goal of therapy for aggressive B-cell lymphomas such as diffuse large B-cell lymphoma (DLBCL) and Burkitt lymphoma (BL) is to achieve cure. Combination chemotherapy with rituximab cures most patients, but those with recurrent disease have a poor prognosis. Medical imaging scans such as computed tomography (CT) and positron emission tomography (PET) are the principal methods to assess response and monitor for disease relapse after therapy but are fundamentally limited by risks of radiation, cost, and a lack of tumor specificity. Novel sequencing-based DNA monitoring methods are capable of quantifying small amounts of circulating tumor DNA (ctDNA) before, during, and after therapy for mature B-cell lymphomas. Detection of ctDNA encoding clonal rearranged variable-diversity-joining (VDJ) receptor gene sequences has demonstrated improved analytical sensitivity and enhanced tumor specificity compared to imaging scans in DLBCL, offering broad clinical applicability across a range of aggressive B-cell lymphomas. Molecular monitoring of ctDNA has vaulted into the spotlight as a promising non-invasive tool with immediate clinical impact on monitoring for recurrence after therapy prior to clinical symptoms. As these clinical observations are validated, ctDNA monitoring needs to be investigated as a tool for response-adapted therapy and as a marker of minimal residual disease upon completion of therapy in aggressive B-cell lymphomas. Molecular monitoring of ctDNA holds tremendous promise that may ultimately transform our ability to monitor disease in aggressive B-cell lymphomas.

Surveillance Scans in Lymphoma: Friend or Foe?

OPINION STATEMENT

Advancements in the treatment of lymphoma over the last few decades have allowed more patients to achieve a remission after the completion of therapy. Due to the improvement in response rates, methods to detect recurrence early and accurately during follow-up, especially in patients with potential curable aggressive lymphomas, are a key. Observation has always involved close clinical follow-up with the use of physical exams and routine labs, but rapid changes in technology have allowed CT scans, PET scans, and MRIs to become an integral part of managing patients with lymphoma. While the utility of scans in initial staging and immediately after completion of therapy is well established, the use of these imaging modalities for monitoring recurrence in lymphoma patients is still controversial. Patient advocacy groups and other regulatory committees have questioned the frequency and in some cases even the need for these tests in patients without evidence of active disease given the concern for radiation-associated health risks. Additionally, the extent to which this form of testing impacts the psyche of our patients is not completely known. Given the numerous questions raised about the benefits, safety, and cost-effectiveness of CT imaging, firm guidelines are needed at this time in standard practice and within our clinical trials to limit the use of surveillance imaging. Such efforts are expected to improve the utility of these scans in asymptomatic patients, reduce healthcare costs, and reduce patient exposure to radiation.

Rethinking clinical response and outcome assessment in a biologic age

Standardized response criteria for lymphoma are critical for the evaluation of new therapies. Widely adopted recommendations, most recently the Lugano classification, have been developed primarily for assessment of conventional chemotherapeutic regimens. More recently, several classes of drugs, including immunomodulatory agents, B cell receptor pathway targeting kinases, and checkpoint (PD-1, PDL-1) inhibitors have demonstrated impressive activity in a broad range of histologies. However, they may be associated with features during treatment suggestive of progressive disease despite clinical benefit. Immune response criteria have been proposed for solid tumors, and a modification is needed to be more applicable to lymphomas. Following treatment, conservative use of imaging is recommended based on clinical indications. As newer targeted agents with unique mechanisms of action are developed, current response and follow-up criteria must be made sufficiently flexible for optimal evaluation.

Routine Imaging for Diffuse Large B-Cell Lymphoma in First Complete Remission Does Not Improve Post-Treatment Survival: A Danish–Swedish Population-Based Study

Purpose

Routine imaging for diffuse large B-cell lymphoma (DLBCL) in first complete remission (CR) is controversial and plays a limited role in detecting relapse. This population-based study compared the survival of Danish and Swedish patients with DLBCL for whom traditions for routine imaging have been different.

Patients and Methods

Patients from the Danish and Swedish lymphoma registries were included according to the following criteria: newly diagnosed DLBCL from 2007 to 2012, age 18 to 65 years, and CR after R-CHOP/CHOEP. Follow-up for Swedish patients included symptom assessment, clinical examinations, and blood tests at 3- to 4-month intervals for 2 years, with longer intervals later in follow-up. Imaging was only recommended when relapse was clinically suspected. Follow-up for Danish patients was similar but included routine imaging (usually computed tomography every 6 months for 2 years).

Results

Danish (n = 525) and Swedish (n = 696) patients with DLBCL had comparable baseline characteristics. Cumulative 2-year progression rate after CR was 6% (95% CI, 4 to 9) for International Prognostic Index (IPI) ≤ 2 versus 21% (95% CI, 13 to 28) for IPI > 2. Age > 60 years (hazard ratio [HR], 2.3; 95% CI, 1.6 to 3.4), elevated lactate dehydrogenase (HR, 2.3; 95% CI, 1.4 to 3.8), B symptoms (HR, 1.7; 95% CI, 1.1 to 2.5), and Eastern Cooperative Oncology Group performance status ≥ 2 (HR, 1.8; 95% CI, 1.0 to 3.0) were associated with worse post-CR survival. Imaging-based follow-up strategy had no impact on survival, neither for all patients nor for IPI-specific subgroups.

Conclusion

DLBCL relapse after first CR is infrequent, and the widespread use of routine imaging in Denmark did not translate into better survival. This favors follow-up without routine imaging and, more generally, a shift of focus from relapse detection to improved survivorship.

Diffuse Large B Cell Lymphoma with Extensive Cutaneous Relapse

Herein, we aimed to report a diffuse large B cell lymphoma (DLBCL) case that had extensive cutaneous relapse with no skin involvement previously. A 59-year-old man presented to hospital in April 2014 with fatigue, anorexia, fever, and anemia. Cervical lymph node biopsy revealed CD20+, BCL2+, MUM1+, BCL6+ high grade B lymphoproliferative neoplasm. After FISH investigation, he was diagnosed as DLBCL. He was given 7 cycles of R-CHOP and achieved remission. However, in November 2014, he had emerging skin lesions that cover nearly all of his body. A control PET-CT revealed diffuse cutaneous involvement. CD20+, BCL2+, MUM1+, BCL6+ high grade B cell lymphoma infiltration was detected with skin biopsy. He was diagnosed as relapse lymphoma, so 2 cycles of R-DHAP were given. There was no treatment response; therefore, R-ICE regimen was started. The patient had achieved second complete remission and his skin lesions were completely regressed. The involvement of skin with CD20+ cells after 7 cycles of rituximab therapy favors that there is a rituximab resistant disease which tends to involve the skin. To conclude, DLBCL may relapse extensively with cutaneous involvement and the best treatment option in these patients is salvage chemotherapy followed by autologous peripheral blood stem cell transplantation.

Imaging of non-Hodgkin lymphomas: diagnosis and response-adapted strategies

Optimal lymphoma management requires accurate pretreatment staging and reliable assessment of response, both during and after therapy. Positron emission tomography with computerized tomography (PET/CT) combines functional and anatomical imaging and provides the most sensitive and accurate methods for lymphoma imaging. New guidelines for lymphoma imaging and recently revised criteria for lymphoma staging and response assessment recommend PET/CT staging, treatment monitoring, and response evaluation in all FDG-avid lymphomas, while CT remains the method of choice for non-FDG-avid histologies. Since interim PET imaging has high prognostic value in lymphoma, a number of trials investigate PET-based, response-adapted therapy for non-Hodgkin lymphomas (NHL). PET response is the main determinant of response according to the new response criteria, but PET/CT has little or no role in routine surveillance imaging, the value which is itself questionable. This review presents from a clinical point of view the evidence for the use of imaging and primarily PET/CT in NHL before, during, and after therapy. The reader is given an overview of the current PET-based interventional NHL trials and an insight into possible future developments in the field, including new PET tracers.

Next-generation surveillance strategies for patients with lymphoma

While remission and cure rates for Hodgkin and non-Hodgkin lymphoma continue to improve, surveillance approaches remain controversial, especially in light of recent reports suggesting limited benefit for routine radiologic assessment. Routine cross-sectional imaging results in considerable patient expense and anxiety, and this approach does not clearly improve patient outcomes. Next-generation approaches including minimal residual disease detection may provide an opportunity to identify relapse early and intervene prior to progression of clinical disease. This review discusses the role of surveillance imaging in Hodgkin and non-Hodgkin lymphoma and provides an introduction to serologic assessment of minimal residual disease. Future studies will need to focus on the clinical application of minimal residual disease surveillance and its ability to predict relapse, treatment response and survival.

Optimal disease surveillance strategies in non-Hodgkin lymphoma

Given the paucity of randomized controlled trial data, defining the ideal strategy for surveillance imaging in patients with non-Hodgkin lymphoma (NHL) has become increasingly challenging. The routine use of frequent surveillance scans has been a common component of patient care. Emerging data from prospective and retrospective observational studies and modeling approaches have highlighted the performance characteristics of imaging modalities and the challenges with this form of secondary screening. The majority of patients with relapsed lymphoma have clinical signs or symptoms that prompt further evaluation, and only a small proportion of patients experience relapse detected on a routine scan while being otherwise asymptomatic. Surveillance imaging is costly, may expose patients to minimal risks of mortality due to radiation-related secondary malignancies, and can lead to false-positive findings, leading to unnecessary biopsies. In addition, no prospective study has demonstrated a significant improvement in overall survival for those patients whose disease is discovered on a routine scan versus those who present with clinical symptoms. In this chapter, we examine the baseline risks of relapse for various NHL subtypes that provide the context for surveillance, review the data on imaging modalities, and establish a framework for discussing optimal surveillance strategies with individual patients. Patients should be counseled on the risks and benefits of routine surveillance imaging and decisions regarding surveillance should be made on an individual basis using patient-specific risk factors, response to induction therapy, and patient preferences with a bias toward using surveillance imaging in the 2 years after treatment only in those NHL patients with the greatest likelihood of benefit.

Utility of routine post-therapy surveillance imaging in diffuse large B-cell lymphoma

PURPOSE

We examined the utility of post-therapy surveillance imaging in a large, prospectively enrolled cohort of patients with diffuse large B-cell lymphoma (DLBCL) from the United States and confirmed our results in an independent cohort of patients from France.

METHODS

Patients with newly diagnosed DLBCL and treated with anthracycline-based immunochemotherapy were identified from the Molecular Epidemiology Resource (MER) of the University of Iowa/Mayo Clinic Lymphoma Specialized Program of Research Excellence and the Léon Bérard Cancer Center, Lyon, France. In those with relapse, details at relapse and outcomes were abstracted from records.

RESULTS

680 individuals with DLBCL were identified from the MER, 552 (81%) of whom achieved remission after induction. 112 of the 552 patients (20%) suffered a relapse. The majority (64%) of relapses were identified before a scheduled follow-up visit. Surveillance imaging detected DLBCL relapse before clinical manifestations in nine out of 552 patients (1.6%) observed after therapy. In the Lyon cohort, imaging identified asymptomatic DLBCL relapse in four out of 222 patients (1.8%). There was no difference in survival after DLBCL relapse in patients detected at scheduled follow-up versus before scheduled follow-up in both the MER (P = .56) and Lyon cohorts (P = .25).

CONCLUSION

The majority of DLBCL relapses are detected outside of planned follow-up, with no difference in outcome in patients with DLBCL detected at a scheduled visit compared with patients with relapse detected outside of planned follow-up. These data do not support the use of routine surveillance imaging for follow-up of DLBCL.

Management of relapsed-refractory diffuse large B cell lymphoma

Relapsed-Refractory Diffuse Large B Cell Lymphoma (RR DLBCL), which accounts for approximately one-third of patients with DLBCL, remains a major cause of morbidity and mortality. Managing RR DLBCL continues to be a challenge to the treating hemato-oncologist. Salvage high-dose chemotherapy followed by autologous stem cell transplantation is the standard of care for chemosensitive relapses in DLBCL. Various salvage regimens are available, but the quest for an optimal regimen continues. The addition of rituximab to the salvage regimen has improved the outcome of RR DLBCL. Several pertinent issues regarding the management of RR DLBCL are discussed in this short review.

Role of routine imaging in detecting recurrent lymphoma: A review of 258 patients with relapsed aggressive non-Hodgkin and Hodgkin lymphoma

After first-line therapy, patients with Hodgkin lymphoma (HL) and aggressive non-HL are followed up closely for early signs of relapse. The current follow-up practice with frequent use of surveillance imaging is highly controversial and warrants a critical evaluation. Therefore, a retrospective multicenter study of relapsed HL and aggressive non-HL (nodal T-cell and diffuse large B-cell lymphomas) was conducted. All included patients had been diagnosed during the period 2002-2011 and relapsed after achieving complete remission on first-line therapy. Characteristics and outcome of imaging-detected relapses were compared with other relapses. A total of 258 patients with recurrent lymphoma were included in the study. Relapse investigations were initiated outside preplanned visits in 52% of the patients. Relapse detection could be attributed to patient-reported symptoms alone or in combination with abnormal blood tests or physical examination in 64% of the patients. Routine imaging prompted relapse investigations in 27% of the patients. The estimated number of routine scans per relapse was 91-255 depending on the lymphoma subtype. Patients with imaging-detected relapse had lower disease burden (P = 0.045) and reduced risk of death following relapse (hazard ratio = 0.62, P = 0.02 in multivariate analysis). Patient-reported symptoms are still the most common factor for detecting lymphoma relapse and the high number of scans per relapse calls for improved criteria for use of surveillance imaging. However, imaging-detected relapse was associated with lower disease burden and a possible survival advantage. The future role of routine surveillance imaging should be defined in a randomized trial.

Symptom-oriented clinical detection versus routine imaging as a monitoring policy of relapse in patients with diffuse large B-cell lymphoma

This study aimed at evaluating the role of routine imaging versus symptom-directed unplanned early outpatient department (OPD) visits in patients with diffuse large B-cell lymphoma (DLBCL) in complete remission (CR) by analyzing the patterns and outcomes of OPD visits for disease monitoring. Patients with DLBCL in CR after treatment in the rituximab era with any OPD monitoring visit were analyzed. A total of 856 OPD visits were recorded: 501 visits were with routine imaging, 322 were without routine imaging and 33 visits (3.9%) were unplanned early visits due to abnormal symptoms. Of the 106 analyzed patients, 15 experienced a relapse (median follow-up duration of 38.1 months). Routine imaging showed an unsatisfactory positive predictive value due to frequent false-positive visits, and a substantial number of patients with false-positive imaging underwent unnecessary biopsies or additional scans. Compared with planned OPD visits, unplanned early visits were highly related to relapse.

Limited clinical benefit for surveillance PET-CT scanning in patients with histologically transformed lymphoma in complete metabolic remission following primary therapy

The optimum follow-up of patients with transformed indolent lymphoma (TrIL) is not well defined. We sought to determine the utility of surveillance positron emission tomography-computed tomography (PET-CT) in patients with TrIL achieving complete metabolic remission (CMR) after primary therapy. We performed a retrospective analysis of patients with TrIL treated at Peter MacCallum Cancer Centre between 2002 and 2012 who achieved CMR after primary therapy who had ≥1 subsequent surveillance PET-CT. Of 55 patients with TrIL, 37 (67 %) received autologous stem cell transplantation as consolidation following chemoimmunotherapy. After a median follow-up of 34 (range 3-101) months, the actuarial 3-year progression-free (PFS) and overall survival (OS) were 77 % (95 %CI 62-86 %) and 88 % (75-94 %), respectively. Of 180 surveillance PET-CT scans, there were 153 true negatives, 4 false positives, 1 false negative, 7 indeterminate and 15 true positives. Considering indeterminate scans as false positives, the specificity of PET-CT for detecting relapse was 94 %, sensitivity was 83 %, positive predictive value was 63 % and negative predictive value was 98 %. All seven subclinical (PET detected) relapses were of low-grade histology; in contrast, all nine relapses with diffuse large B cell lymphoma (DLBCL) were symptomatic. In our cohort of patients with TrIL achieving CMR, PET-CT detected subclinical low-grade relapses but all DLBCL relapses were accompanied by clinical symptoms. Thus, surveillance imaging of patients with TrIL achieving CMR is of limited clinical benefit. PET-CT should be reserved for evaluation of clinically suspected relapse.

Delivering maximum clinical benefit at an affordable price: engaging stakeholders in cancer care

Cancer costs continue to increase alarmingly despite much debate about how they can be reduced. The oncology community needs to take greater responsibility for our own practice patterns, especially when using expensive tests and treatments with marginal value: we cannot continue to accept novel therapeutics with very small benefits for exorbitant prices. Patients, payers, and pharmaceutical communities should be constructively engaged to communicate medically and economically possible goals, and eventually, to reduce use and costs. Diagnostic tests and treatments should have to show true value to be added to existing protocols. In this article, we discuss three key drivers of costs: end-of-life care patterns, medical imaging, and drugs. We propose health-care models that have the potential to decrease costs and discuss solutions to maintain clinical benefit at an affordable price.

Current role of FDG PET/CT in lymphoma

The management approach in Hodgkin's (HL) and high-grade non-Hodgkin's lymphomas (NHL) has shifted towards reducing the toxicity and long-term adverse effects associated with treatment while maintaining favorable outcomes in low-risk patients. The success of an individualized treatment strategy depends largely on accurate diagnostic tests both at staging and during therapy. In this regard, positron emission tomography (PET) using fluorodeoxyglucose (FDG) with computed tomography (CT) has proved effective as a metabolic imaging tool with compelling evidence supporting its superiority over conventional modalities, particularly in staging and early evaluation of response. Eventually, this modality was integrated into the routine staging and restaging algorithm of lymphomas. This review will summarize the data on the proven and potential utility of PET/CT imaging for staging, response assessment, and restaging, describing current limitations of this imaging modality.

The ASH Choosing Wisely® campaign: five hematologic tests and treatments to question

Choosing Wisely® is a medical stewardship and quality improvement initiative led by the American Board of Internal Medicine Foundation in collaboration with leading medical societies in the United States. The ASH is an active participant in the Choosing Wisely® project. Using an iterative process and an evidence-based method, ASH has identified 5 tests and treatments that in some circumstances are not well supported by evidence and which in certain cases involve a risk of adverse events and financial costs with low likelihood of benefit. The ASH Choosing Wisely® recommendations focus on avoiding liberal RBC transfusion, avoiding thrombophilia testing in adults in the setting of transient major thrombosis risk factors, avoiding inferior vena cava filter usage except in specified circumstances, avoiding the use of plasma or prothrombin complex concentrate in the nonemergent reversal of vitamin K antagonists, and limiting routine computed tomography surveillance after curative-intent treatment of non-Hodgkin lymphoma. We recommend that clinicians carefully consider anticipated benefits of the identified tests and treatments before performing them.

The ASH Choosing Wisely® campaign: five hematologic tests and treatments to question

Choosing Wisely® is a medical stewardship and quality improvement initiative led by the American Board of Internal Medicine Foundation in collaboration with leading medical societies in the United States. The ASH is an active participant in the Choosing Wisely® project. Using an iterative process and an evidence-based method, ASH has identified 5 tests and treatments that in some circumstances are not well supported by evidence and which in certain cases involve a risk of adverse events and financial costs with low likelihood of benefit. The ASH Choosing Wisely® recommendations focus on avoiding liberal RBC transfusion, avoiding thrombophilia testing in adults in the setting of transient major thrombosis risk factors, avoiding inferior vena cava filter usage except in specified circumstances, avoiding the use of plasma or prothrombin complex concentrate in the nonemergent reversal of vitamin K antagonists, and limiting routine computed tomography surveillance after curative-intent treatment of non-Hodgkin lymphoma. We recommend that clinicians carefully consider anticipated benefits of the identified tests and treatments before performing them.

The utility of lactate dehydrogenase in the follow up of patients with diffuse large B-cell lymphoma

BACKGROUND

Serum lactate dehydrogenase is a non-specific marker for lymphoma whose prognostic significance is well established for both indolent and aggressive lymphomas at the time of diagnosis. The performance characteristics of this enzyme in predicting relapse in patients with diffuse large B-cell lymphoma has not been well studied.

METHODS

This study compared serum lactate dehydrogenase levels in 27 patients with diffuse large B-cell lymphoma who relapsed after sustaining a complete response versus 87 patients who did not relapse. For relapsed patients, the serum lactate dehydrogenase level at relapse was compared with the level three months before (considered baseline). For non-relapsed patients, the last two levels during follow-up were compared. For statistical analysis the T-test was used to compare differences in mean values between groups. The sensitivity, specificity, positive and negative predictive values for serum lactate dehydrogenase in detecting relapse compared to confirmatory imaging were calculated.

RESULTS

At relapse, only 33% patients had increases in serum lactate dehydrogenase above the upper limit of normal. The mean increase was 1.2-fold above the upper limit of normal for relapsed vs. 0.83 for those who did not relapse (p-value = 0.59). The mean increase in serum lactate dehydrogenase, from baseline, was 1.1-fold in non-relapsed vs. 1.3 in relapsed patients (p-value = 0.3). The likelihood ratio of relapse was 4.65 for patients who had 1.5-fold increases in serum lactate dehydrogenase above baseline (p-value = 0.03). The sensitivity, specificity, positive and negative predictive values of 1.5-fold increases for detecting relapse, compared to clinical and imaging findings were 0.18, 0.95, 0.55, and 0.79, respectively.

CONCLUSION

A 1.5-fold increase in serum lactate dehydrogenase, over a period of 3 months, is associated with increased likelihood of relapse from diffuse large B-cell lymphoma.

Limited role for surveillance PET-CT scanning in patients with diffuse large B-cell lymphoma in complete metabolic remission following primary therapy

Background:

The usefulness of positron emission tomography with computed tomography (PET–CT) in the surveillance of patients with diffuse large B-cell lymphoma (DLBCL) in complete metabolic remission after primary therapy is not well studied.

Methods:

We performed a retrospective review of our database between 2002 and 2009 for patients with de novo DLBCL who underwent surveillance PET–CT after achieving complete metabolic response (CMR) following primary therapy.

Results:

Four-hundred and fifty scans were performed in 116 patients, with a median follow-up of 53 (range 8–133) months from completion of therapy. Thirteen patients (11%) relapsed: seven were suspected clinically and six were subclinical (all within first 18 months). The positive predictive value in patients with international prognostic index (IPI) <3 was 56% compared with 80% in patients with IPI⩾3. Including indeterminate scans, PET–CT retained high sensitivity 95% and specificity 97% for relapse.

Conclusion:

Positron emission tomography with computed tomography is not useful in patients for the majority of patients with diffuse large B-cell lymphoma in CMR after primary therapy, with the possible exception of patients with baseline IPI ⩾3 in the 18 months following completion of primary therapy. This issue could be addressed by a prospective clinical trial.

Underperformance of gallium-67 scan is greater in relapse than in initial staging, compared with FDG PET

PURPOSE

The purpose of this study is to evaluate the performance of gallium-67 scan (GS) and F-18 fluorodeoxyglucose (FDG) PET scan in lymphoma staging and recurrence detection by comparing the 2 imaging studies in the same patient.

MATERIALS AND METHODS

A total of 42 patients from the period between July 2002 and May 2006 were included in this study. Of the 42 patients, 6 had Hodgkin disease and 36 had non-Hodgkin lymphomas. All of them underwent one or more FDG PET scans and also underwent corresponding GS performed within 7 days of FDG PET, for staging or detection of lymphoma recurrence. Among the non-Hodgkin lymphoma cases, 18 were diffuse large B-cell lymphoma, 10 were follicular center cell lymphoma, and 8 were of other types. Of the total 46 pairs of imaging performed in these 42 patients, 27 were for staging, and 19 for restaging after recurrence.

RESULTS

In all these studies, FDG PET detected 230 lesion sites, whereas GS detected 85 lesion sites. All of the lesions detected by GS were noted on FDG PET, whereas GS detected only 37.0% of the lesions detected by FDG PET. Among the 27 studies for staging, FDG PET detected 120 lesions, whereas GS detected 68 lesions (56.7%). In the 19 images taken for relapse, FDG PET detected 110 lesions, whereas GS detected only 17 (15.5%).

CONCLUSIONS

FDG PET is superior to GS in staging and detecting all types of lymphoma. The difference is notably more significant in recurrence detection.

Lymphopenia following the completion of first-line therapy predicts early relapse in patients with diffuse large B cell lymphoma

Early relapse is a parameter that affects clinical outcomes in relapsed diffuse large B cell lymphoma (DLBCL). The prognostic value of lymphopenia following the completion of first-line therapy and the relationship between lymphopenia and early relapse are unknown. Therefore, we studied the role of absolute lymphocyte count (ALC) on early relapse. We retrospectively analyzed de novo DLBCL patients who were treated with rituximab-containing treatment between 2003 and 2010. The median age at the time of diagnosis of 59 DLBCL patients was 71 years. We identified no association between ALC at diagnosis and ALC following the completion of first-line therapy. Among all patients analyzed, 13 (22%) patients were confirmed to exhibit early relapse. Low ALC following the completion of first-line therapy was significantly associated with early relapse by univariate analysis [hazard ratio (HR) = 4.05; 95% confidence interval (CI), 1.11-14.73; P = 0.02] and multivariate analysis (HR = 4.66; 95% CI, 1.24-17.48; P = 0.023). The low ALC group tended to have worse outcomes than the high ALC group with lower rates of progression-free survival (66% and 74%, respectively; P = 0.13) and overall survival (74% and 86%, respectively; P = 0.09), but these differences did not reach statistically. Lymphopenia following the completion of first-line therapy can be used as a marker to predict early relapse.

18F-FDG-PET/CT in the surveillance of patients with lymphoma: detection of asymptomatic recurrences

AIM

To assess the diagnostic accuracy of (18)F-FDG-PET/CT in detecting asymptomatic recurrences in patients with lymphoma. To define uptake patterns of recurrence indicative of recurrence.

MATERIAL AND METHODS

Those patients with lymphoma who fulfilled the following inclusion criteria of clinical complete remission and negative PET/CT study were included retrospectively and longitudinally. Conventional surveillance of these patients was performed only by (18)F-FDG PET/CT following a standardized procedure. Pathologic locations (supra- and infradiaphragmatic) and their character (single or multiple) were analyzed in order to determine reliable metabolic patterns of recurrence. The final diagnosis was established by histopathological analysis or clinical follow-up greater than 8 months.

RESULTS

A total of 199 explorations belonging to 106 patients with lymphoma were included. Of these patients, 59 had Hodgkin's lymphoma and 47 non-Hodgkin's lymphoma. There was suspicion of relapse from the metabolic point of view in 27 of the PET/CT scans. Of these, 14 (10 patients) were false positive (FP), and 13 (8 patients) true positive. The remaining studies were true negative, no false negatives being detected. The pattern most frequently related to recurrence was infradiaphragmatic lymph node involvement while most of the FP had isolated supradiaphragmatic involvement. Sensitivity, specificity, PPV, NPV and diagnostic accuracy of PET/CT parameters for the study were 100%, 92%, 48%, 100% and 93%, respectively.

CONCLUSION

(18)F-FDG-PET/CT is a sensitive technique in the detection of asymptomatic recurrences in patients with lymphoma during their follow-up. Multiple character and infradiaphragmatic locations were the patterns that best correlated to the diagnosis of recurrence.

Role of Functional Imaging in the Management of Lymphoma

18-F-fluorodeoxyglucose (FDG) –positron emission tomography (PET), and more recently PET/computed tomography (CT), is the most sensitive and specific imaging technique currently available for patients with lymphoma. Nevertheless, despite being increasingly used in pretreatment assessment, midtreatment evaluation of response, post-treatment restaging, and surveillance during follow-up of patients with lymphoma, its impact on clinical outcome in most clinical situations remains to be confirmed. PET/CT provides its greatest clinical benefit in the post-treatment evaluation of Hodgkin's lymphoma and diffuse large B-cell lymphoma; however, the role of metabolic imaging in other indications and in other histologies remains to be demonstrated. Ongoing risk-adapted studies will hopefully provide evidence for clinical improvement on the basis of altering treatment as a result of interim PET results. Efforts are ongoing to better standardize the conduct and interpretation of FDG-PET scans. FDG-PET has the potential to improve lymphoma patient management; however, its usefulness will likely vary by histology, stage, therapy, and clinical setting.

Surveillance computed tomography scans for patients with lymphoma: is the risk worth the benefits?

BACKGROUND

Concerns regarding the risks of cancer and cancer-related death as a result of radiation from computed tomography (CT) scans and the lack of data demonstrating a survival advantage for surveillance CT scans following lymphoma therapy have raised questions regarding their benefit. We compared the radiation-related lifetime cancer incidence (LCI) and mortality risks (LCMRs) associated with CT scans for staging and surveillance of non-Hodgkin lymphoma (NHL) and Hodgkin lymphoma (HL) with the cumulative probability of lymphoma death (CPLD) during surveillance.

PATIENTS AND METHODS

The LCI and LCMR were calculated using published estimates of the cumulative organ-specific radiation doses from full-body CT scans and sex-, age-, and organ-dependent cancer risks per 0.1 Gy provided by the Biologic Effects of Ionizing Radiations VII report. Surveillance, Epidemiology, and End Results (SEER) data were used to identify cases between 2000 and 2006 from 17 SEER registries and calculate CPLD for specified cohorts.

RESULTS

For a 70-year-old patient, a single full-body CT examination is associated with a LCI of 0.044% and 0.057%, and a LCMR of 0.032% and 0.044% for males and females, respectively. For 20-year-old patients the LCMRs were 0.071% for men and 0.108% for women. The LCI and LCMR were lower for males and were markedly less than the CPLD at 5 years for most lymphoma subtypes, but relevant for younger women with HL.

CONCLUSION

Although the LCMR from CT scans is small compared with lymphoma-related deaths for most subgroups, these data should be discussed with patients in formulating plans for surveillance following lymphoma therapy.

Response evaluation criteria for peripheral nodal lymphoma in dogs (v1.0)--a Veterinary Cooperative Oncology Group (VCOG) consensus document

Standardized assessment of response to therapy for lymphoma in dogs is lacking, making critical comparisons of treatment protocols difficult. This Veterinary Cooperative Oncology Group (VCOG) consensus document, based on the recommendations of a subcommittee of ACVIM board-certified veterinary oncologists, was unanimously adopted at the 29th Annual Conference of the Veterinary Cancer Society (VCS) by the VCOG membership. It has integrated guidance from the response assessment criteria established for lymphoma in human patients using standards available in routine veterinary oncology practices that are simple, repeatable and consistently applicable. These guidelines are intended only for use in dogs, where peripheral lymphadenopathy represents the principal component of their disease and as such do not critically assess extranodal disease (e.g., primary cutaneous, central nervous system, gastrointestinal). It is hoped these guidelines will be widely adopted and serve to facilitate the comparison of current and future treatment protocols used in the therapy of dogs.