Surveillance computed tomography imaging and detection of relapse in intermediate- and advanced-stage pediatric Hodgkin's lymphoma: a report from the Children's Oncology Group

[18F]FDG PET-MR in the Evaluation and Follow-Up of Incidental Bone Ischemic Lesions in a Mono-Center Cohort of Pediatric Patients Affected by Hodgkin's Lymphoma

Hodgkin's lymphoma (HL) is one of the neoplasms with the best prognosis in children, adolescents and young adults, but sufferers are burdened by the possibility of developing adverse effects such as Bone Ischemic Lesions (BILs) which are lesions of the bone caused by the loss of/reduction in blood flow. The main goal of this retrospective study was to evaluate the role of [¹⁸F]FDG-PET-MR in the early detection of BILs in a single-center cohort of uniformly treated pediatric HL patients. BILs were assessed through PET-MR images as the appearance of medullary lesion surrounded by a serpiginous, tortuous border. From 2017 to 2022, 10/53 (18.9%) HL patients developed BILs which were mostly (8/10 patients) multifocal. Overall, 30 lesions were identified in the 10 asymptomatic patients, all with the above-mentioned features at MR and with very low [¹⁸F]FDG uptake. BILs were incidentally detected during HL therapy (n = 6) and follow-up (n = 4), especially in the long bones (66.7%). No factors correlated with the occurrence of BIL were identified. No patients developed complications. PET-MR is a sensitive combined-imaging technique for detecting BILs that are asymptomatic and self-limiting micro-ischemic lesions. BILs can be monitored by clinical follow-up alone both during and after therapy.

Characterizing and quantifying low-value diagnostic imaging internationally: a scoping review

BACKGROUND

Inappropriate and wasteful use of health care resources is a common problem, constituting 10-34% of health services spending in the western world. Even though diagnostic imaging is vital for identifying correct diagnoses and administrating the right treatment, low-value imaging-in which the diagnostic test confers little to no clinical benefit-is common and contributes to inappropriate and wasteful use of health care resources. There is a lack of knowledge on the types and extent of low-value imaging. Accordingly, the objective of this study was to identify, characterize, and quantify the extent of low-value diagnostic imaging examinations for adults and children.

METHODS

A scoping review of the published literature was performed. Medline-Ovid, Embase-Ovid, Scopus, and Cochrane Library were searched for studies published from 2010 to September 2020. The search strategy was built from medical subject headings (Mesh) for Diagnostic imaging/Radiology OR Health service misuse/Medical overuse OR Procedures and Techniques Utilization/Facilities and Services Utilization. Articles in English, German, Dutch, Swedish, Danish, or Norwegian were included.

RESULTS

A total of 39,986 records were identified and, of these, 370 studies were included in the final synthesis. Eighty-four low-value imaging examinations were identified. Imaging of atraumatic pain, routine imaging in minor head injury, trauma, thrombosis, urolithiasis, after thoracic interventions, fracture follow-up and cancer staging/follow-up were the most frequently identified low-value imaging examinations. The proportion of low-value imaging varied between 2 and 100% inappropriate or unnecessary examinations.

CONCLUSIONS

A comprehensive list of identified low-value radiological examinations for both adults and children are presented. Future research should focus on reasons for low-value imaging utilization and interventions to reduce the use of low-value imaging internationally.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO: CRD42020208072.

Outcome of Children and Adolescents with Recurrent Classical Hodgkin Lymphoma: The Italian Experience

The objective of this study was to identify prognostic factors for children and adolescents with relapsed or progressive classical Hodgkin’s lymphoma (cHL) to design salvage therapy tailored to them. We analyzed a homogeneous pediatric population, diagnosed with progressive/relapsed cHL previously enrolled in two subsequent protocols of the Italian Association of Pediatric Hematology and Oncology in the period 1996−2016. There were 272 eligible patients, 17.5% of treated patients with cHL. Overall survival (OS) and event-free survival (EFS) after a 10-year follow-up were 65.3% and 53.3%, respectively. Patients with progressive disease (PD), advanced stage at recurrence, and ≥5 involved sites showed a significantly worse OS. PD, advanced stage, and extra-nodal involvement at recurrence were significantly associated with a poorer EFS. Multivariable analysis identified three categories for OS based on the type of recurrence and number of localizations: PD and ≥5 sites: OS 34%; PD and <5 sites: OS 56.5%; relapses: OS 73.6%. Four categories were obtained for EFS based on the type of recurrence and stage: PD and stage 3−4: EFS 25.5%; PD and stage 1−2: EFS 43%; relapse and stage 3−4: EFS 55.4%; relapse and stage 1−2: EFS 72.1%. Patients with PD, in advanced stage, or with ≥5 involved sites had a very poor survival and they should be considered refractory to first- and second-line standard chemotherapy. Probably, they should be considered for more innovative approaches since the first progression. Conversely, patients who relapsed later with localized disease had a better prognosis, and they could be considered for a conservative approach.

Guideline for the first-line management of Classical Hodgkin Lymphoma - A British Society for Haematology guideline

This guideline was compiled according to the British Society for Haematology (BSH) process at https://b-s-h.org.uk/media/16732/bsh-guidance-development-process-dec-5-18.pdf. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) nomenclature was used to evaluate levels of evidence and to assess the strength of recommendations. The GRADE criteria can be found at http://www.gradeworkinggroup.org. Recommendations are based on a review of the literature using Medline, PubMed/Medline and Cochrane searches beginning from 2013 up to January 2021. The following search terms were used: [Hodgkin lymphoma OR Hodgkin disease] NOT non-Hodgkin; AND [chemotherapy OR radiotherapy]; AND [elderly]; AND [teenage OR adolescent OR young adult]; AND [pregnancy]. Filters were applied to include only publications written in English, studies carried out in humans, clinical conferences, congresses, clinical trials, clinical studies, meta-analyses, multicentre studies and randomised controlled trials. References pre-2013 were taken from the previous version of this guideline.¹ Review of the manuscript was performed by the British Society for Haematology (BSH) Guidelines Committee Haematology Oncology Taskforce, the BSH Guidelines Committee and the Haematology Oncology sounding board of BSH.

A systematic review of evidence for and against routine surveillance imaging after completing treatment for childhood extracranial solid tumors

BACKGROUND

Regular off-treatment imaging is often used to assess for recurrence of disease after childhood cancer treatment. It is unclear if this increases survival, or what burden surveillance places on patients, families, or health-care services. This systematic review examines the impact of routine surveillance imaging after treatment of pediatric extracranial solid tumors.

METHODS

Collaborative patient and public involvement informed the design and interpretation of this work. Thirteen electronic databases, conference proceedings, and trial registries were searched alongside reference list checking and forward citation searching from 1990 onwards. Studies were screened and data were extracted by two researchers. Risk of bias was assessed using a modified ROBINS-I tool. Relevant outcomes were overall survival, psychological distress indicators, number of imaging tests, cost-effectiveness, and qualitative data regarding experiences of surveillance programs. PROSPERO (CRD42018103764).

RESULTS

Of 17 727 records identified, 55 studies of 10 207 patients were included. All studies used observational methods. Risk of bias for all except one study was moderate, serious, or critical. Data were too few to conduct meta-analysis; however, narrative synthesis was performed. Surveillance strategies varied, and poorly reported, involving many scans and substantial radiation exposure (eg, neuroblastoma, median 133.5 mSv). For most diseases, surveillance imaging was not associated with increased overall survival, with the probable exception of Wilms tumor. No qualitative or psychological distress data were identified.

CONCLUSIONS

At present, there is insufficient evidence to evaluate the effects of routine surveillance imaging on survival in most pediatric extracranial solid tumors. More high-quality data are required, preferably through randomized controlled trials with well-conducted qualitative elements.

Hodgkin Lymphoma in Children and Adolescents: Advances in Pathology, Diagnosis, and Treatment Strategies

Strategies used for the treatment of children with Hodgkin lymphoma (HL) over the last four decades have resulted in excellent long-term survivals. However, the short- and long-term treatment-associated morbidities were high. In an attempt to reduce complications, the current treatment strategies apply initial risk stratification principles based on certain host and tumor risk factors to help assign patients to the appropriate risk group and tailor therapy based on response to chemotherapy (CTR). Radiotherapy (RT) was only given to certain groups of patients who show suboptimal response to CTR. Enrollment of patients in clinical trials allowed testing newer treatment strategies, which has improved the outcome significantly. High-dose CTR with stem cell support remains the mainstay of treatment for relapsed and refractory HL. Newer targeted medications are being increasingly used for the treatment of patients with relapsed and refractory HL, but results are variable. In this review report, we give extensive account about the pathophysiology, clinical presentation, histopathological diagnosis, modern investigation techniques, the most recent risk adapted treatment strategies, and the use and effect of novel medications. In addition, we discuss in details the short- and long-term therapy-related complications and future prospects in the management of HL.

PET in Pediatric Lymphoma

Although fluorodeoxyglucose PET/MR imaging is a promising new modality, there is not yet enough data to support its routine use for staging or surveillance of children with lymphoma. PET/MR imaging protocols are still under development, and its availability globally is limited. The cost-benefit of using PET/MR imaging has not yet been established, especially because annual post-treatment surveillance imaging with fluorodeoxyglucose PET is not necessary in most patients with lymphoma. Further research into the use of PET/MR imaging in pediatric oncology patients is needed with continued collaborations among institutions.

Surveillance imaging in pediatric lymphoma

Current therapies used in treating children with Hodgkin lymphoma and many histological subtypes of non-Hodgkin lymphoma have resulted in overall survival rates exceeding 90% in many instances. With increasing concerns related to the cost of radiologic imaging, exposure to ionizing radiation, and potential false-positive results, the role of routine off-therapy surveillance imaging has been called into question. Although radiologic imaging plays an important role in diagnosing and assessing treatment response, in these children - the majority of whom have an excellent outcome following completion of therapy - there is an opportunity to dramatically reduce the number of off-therapy imaging evaluations. This review summarizes several recent studies in both Hodgkin and non-Hodgkin lymphoma providing evidence to support these efforts. In addition, we propose a surveillance imaging strategy that uses a novel risk-adapted and response-based approach to determine which children would most benefit from off-therapy imaging surveillance.

Impact of Surveillance Imaging Modality on Survival After Recurrence in Patients With Favorable-Histology Wilms Tumor: A Report From the Children's Oncology Group

PURPOSE

The use of computed tomography (CT) for routine surveillance to detect recurrence in patients with Wilms tumor (WT) has increased in recent years. The utility of CT, despite increased risk and cost, to improve outcome for these patients is unknown. We conducted a retrospective analysis with patients enrolled in the fifth National Wilms Tumor Study (NWTS-5) to determine if surveillance with CT correlates with improved overall survival (OS) after recurrence compared with chest x-ray (CXR) and abdominal ultrasound (US).

PATIENTS AND METHODS

Overall, 281 patients with recurrent unilateral favorable-histology WT were reviewed to assess how WT recurrence was detected: sign/symptoms (SS), surveillance imaging (SI) with CT scan, or SI with CXR/US.

RESULTS

The estimated 5-year OS rate after relapse was 67% (95% CI, 61% to 72%). Twenty-five percent of recurrences were detected with SS; 48.5%, with CXR/US; and 26.5%, with CT. Patients with SS had a 5-year OS rate of 59% (95% CI, 46% to 72%) compared with 70% (95% CI, 63% to 77%; P = .23) for those detected by SI. Recurrences detected by CT had a shorter median time from diagnosis to recurrence (0.60 years) compared with SS (0.91 years) or CXR/US (0.86 years; P = .003). For recurrences detected by SI, more tumor foci at relapse ( P < .001) and size of the largest focus greater than 2 cm ( P = .02) were associated with inferior OS. However, there was no difference in OS after relapse when recurrence was detected by CT versus CXR/US (5-year OS rate, 65% v 73%; P = .20).

CONCLUSION

In patients with favorable-histology WT, elimination of CT scans from surveillance programs is unlikely to compromise survival but would result in substantial reduction in radiation exposure and health care costs.

Staging and following common pediatric malignancies: MRI versus CT versus functional imaging

Most pediatric malignancies require some form of cross-sectional imaging, either for staging or response assessment. The majority of these are solid tumors and this review addresses the role of MRI, as well as other cross-sectional and functional imaging techniques, for evaluating the most common pediatric solid tumors. The primary emphasis is on neuroblastoma, hepatoblastoma and Wilms tumor, three of the most common non-central-nervous-system (CNS) pediatric solid tumors encountered in young children. The initial focus will be a review of the imaging techniques and approaches used for diagnosis, staging and early post-treatment response assessment, followed by a discussion of the role surveillance imaging plays in pediatric oncology and a brief review of other emerging imaging techniques. The lessons learned here can be applied to most other pediatric tumors, including rhabdomyosarcoma, Ewing sarcoma and osteosarcoma, as well as germ cell tumors, neurofibromatosis and other rare tumors. Although lymphoma, in particular Hodgkin lymphoma, represents one of the more common pediatric malignancies, this is not discussed in detail here. Rather, many of the lessons that we have learned from lymphoma, specifically with regard to how we integrate both anatomical imaging and functional imaging techniques, is applied to the discussion of the other pediatric solid tumors.

Early-stage Hodgkin lymphoma in the modern era: simulation modelling to delineate long-term patient outcomes

We developed a novel simulation model integrating multiple data sets to project long-term outcomes with contemporary therapy for early-stage Hodgkin lymphoma (ESHL), namely combined modality therapy (CMT) versus chemotherapy alone (CA) via ¹⁸ F-fluorodeoxyglucose positron emission tomography response-adaption. The model incorporated 3-year progression-free survival (PFS), probability of cure with/without relapse, frequency of severe late effects (LEs), and 35-year probability of LEs. Furthermore, we generated estimates for quality-adjusted life years (QALYs) and unadjusted survival (life years, LY) and used model projections to compare outcomes for CMTversusCA for two index patients. Patient 1: a 25-year-old male with favourable ESHL (stage IA); Patient 2: a 25-year-old female with unfavourable ESHL (stage IIB). Sensitivity analyses assessed the impact of alternative assumptions for LE probabilities. For Patient 1, CMT was superior to CA (CMT incremental gain = 0·11 QALYs, 0·21 LYs). For Patient 2, CA was superior to CMT (CA incremental gain = 0·37 QALYs, 0·92 LYs). For Patient 1, the advantage of CMT changed minimally when the proportion of severe LEs was reduced from 20% to 5% (0·15 QALYs, 0·43 LYs), whereas increasing the severity proportion for Patient 2's LEs from 20% to 80% enhanced the advantage of CA (1·1 QALYs, 6·5 LYs). Collectively, this detailed simulation model quantified the long-term impact that varied host factors and alternative contemporary treatments have in ESHL.

Post-treatment surveillance imaging in lymphoma

Appropriate post-treatment management of patients with lymphoma has been controversial, with imaging frequently performed as post-treatment surveillance. The goal of post-treatment imaging is to identify relapse prior to clinical symptoms, when the burden of disease is lower and the possibility of effective salvage therapy and cure are greater. However, little data exist to support the performance of surveillance imaging after completion of treatment, with the vast majority of studies suggesting there is no clinical benefit to surveillance imaging in asymptomatic patients. Ongoing efforts seek to identify a subset of patients with a higher risk of relapse that might benefit from surveillance imaging, though financial and other costs associated with imaging are non-negligible and must be considered. Here we summarize the current data regarding post-treatment surveillance imaging in lymphoma.

Utility of Routine Surveillance Imaging for Hodgkin Disease following Autologous Transplant: Experiences from a Single Institution

BACKGROUND

Surveillance scans performed after autologous stem cell transplant (auto-HCT) for patients with Hodgkin disease (HD) have no proven survival benefit.

METHODS

We studied survival differences among patients with HD after auto-HCT whose recurrences were detected on clinical history and exam, versus those detected on routine surveillance scan.

RESULTS

Among the 98 patients with HD that underwent auto-HCT from 2000 to 2014 at our institution, 30 relapsed, of which 21 were detected radiologically and 9 clinically. There were no statistically significant differences in patient characteristics between the 2 groups. The median time to progression was 118 days for the clinical cohort and 284 days for the radiological cohort (p = 0.05). Median overall survival (OS) was 728 days for the clinical cohort, and was not reached for the radiological cohort (p = 0.02).

DISCUSSION

In our review, most patients with HD after auto-HCT were diagnosed radiologically. Patients whose relapse was diagnosed clinically were likely to be detected earlier and have a shorter OS. Patients with aggressive disease may be detected when clinically relevant, regardless of scanning. Routine scanning may not be necessary in the majority of patients with HD following auto-HCT.

Routine surveillance imaging after end of therapy for pediatric extracranial tumors: A retrospective analysis

Frequent surveillance imaging is routine practice for pediatric patients after cancer therapy. This retrospective study evaluated the follow-up of 301 children with extracranial tumors diagnosed between 2002 and 2012, at a tertiary pediatric cancer center in Beirut, Lebanon. Recurrence occurred in 15% of patients, at a median of 12 months after end of primary therapy. Outcome was not different comparing patients with recurrence detected via imaging surveillance versus clinically. False positive findings in 55 patients led to further interventions. These results raise important questions regarding benefit of current surveillance practices as standard care, especially in countries with limited resources.

Utility of routine surveillance imaging for diffuse large B-cell lymphoma post autologous transplant: A single center experience

Surveillance scans after autologous stem cell transplant (auto-HCT) for patients with relapsed/refractory (RR) diffuse large B Cell lymphoma (DLBCL) have no proven survival benefit. We studied survival differences among patients with RR DLBCL post auto-HCT whose recurrences were detected clinically versus with routine surveillance imaging. Among the 139 patients with RR DLBCL that underwent auto-HCT from 2000 to 2014 at our institution, 37 relapsed: 21 clinical and 16 radiological. The median time to progression was 167 days for the clinical cohort and 565 days for the radiological cohort (p = 0.03), and median overall survival (OS) was 587 days and not reached, respectively (p = 0.006). Most patients with relapsed DLBCL after auto-HCT were diagnosed clinically and were likely to be detected earlier and have a shorter OS. Relapse in patients with aggressive disease will likely be detected when clinically apparent, and the outcome of these patients is independent of the way the relapse is diagnosed. Thus, universal scanning after auto-HCT appears to have little benefit.

Effect of Routine Surveillance Imaging on the Outcomes of Patients With Classical Hodgkin Lymphoma After Autologous Hematopoietic Cell Transplantation

BACKGROUND

Patients with relapsed and refractory classical Hodgkin lymphoma (cHL) are often treated with autologous hematopoietic cell transplantation (auto-HCT). After auto-HCT, most transplant centers implement routine surveillance imaging to monitor for disease relapse; however, there is limited evidence to support this practice.

PATIENTS AND METHODS

In this multicenter, retrospective study, we identified cHL patients (n = 128) who received auto-HCT, achieved complete remission (CR) after transplantation, and then were followed with routine surveillance imaging. Of these, 29 (23%) relapsed after day 100 after auto-HCT. Relapse was detected clinically in 14 patients and with routine surveillance imaging in 15 patients.

RESULTS

When clinically detected relapse was compared with to radiographically detected relapse respectively, the median overall survival (2084 days [range, 225-4161] vs. 2737 days [range, 172-2750]; P = .51), the median time to relapse (247 days [range, 141-3974] vs. 814 days [range, 96-1682]; P = .30) and the median postrelapse survival (674 days [range, 13-1883] vs. 1146 days [range, 4-2548]; P = .52) were not statistically different. In patients who never relapsed after auto-HCT, a median of 4 (range, 1-25) surveillance imaging studies were performed over a median follow-up period of 3.5 years.

CONCLUSION

A minority of patients with cHL who achieve CR after auto-HCT will ultimately relapse. Surveillance imaging detected approximately half of relapses; however, outcomes were similar for those whose relapse was detected using routine surveillance imaging versus detected clinically in between surveillance imaging studies. There appears to be limited utility for routine surveillance imaging in cHL patients who achieve CR after auto-HCT.

Current Role of FDG-PET in Pediatric Hodgkin's Lymphoma

Hodgkin's lymphoma is one of the most curable pediatric cancers with long-term survival rates exceeding 90% following intensive treatment. Collaborative group studies worldwide aim on reduction or elimination of radiotherapy to avoid potentially life-limiting late effects especially second cancers and cardiovascular diseases. Large prospective trials have integrated early response FDG-PET scans to identify adequate responders to chemotherapy in whom radiotherapy may safely be omitted. The criteria for interpretation of early response PET have changed during the past years and will be further refined based on trial results. FDG-PET is also systematically used to assess initial disease involvement of pediatric Hodgkin's lymphoma and could replace bone marrow biopsy. This article summarizes the role of FDG-PET in staging and response assessment focusing on large pediatric trials, the criteria for PET interpretation and pitfalls.

Prognostic Factors and a New Prognostic Index Model for Children and Adolescents with Hodgkin's Lymphoma Who Underwent Autologous Hematopoietic Stem Cell Transplantation: A Multicenter Study of the Turkish Pediatric Bone Marrow Transplantation Study Group

Objective:

The prognostic factors and a new childhood prognostic index after autologous hematopoietic stem cell transplantation (AHSCT) in patients with relapsed/refractory Hodgkin’s lymphoma (HL) were evaluated.

Materials and Methods:

The prognostic factors of 61 patients who underwent AHSCT between January 1990 and December 2014 were evaluated. In addition, the Age-Adjusted International Prognostic Index and the Childhood International Prognostic Index (CIPI) were evaluated for their impact on prognosis.

Results:

The median age of the 61 patients was 14.8 years (minimum-maximum: 5-20 years) at the time of AHSCT. There were single relapses in 28 patients, ≥2 relapses in eight patients, and refractory disease in 25 patients. The chemosensitivity/chemorefractory ratio was 36/25. No pretransplant radiotherapy, no remission at the time of transplantation, posttransplant white blood cell count over 10x10³/µL, posttransplant positron emission tomography positivity at day 100, and serum albumin of <2.5 g/dL at diagnosis were correlated with progression-free survival. No remission at the time of transplantation, bone marrow positivity at diagnosis, and relapse after AHSCT were significant parameters for overall survival.

Conclusion:

The major factors affecting the progression-free and overall survival were clearly demonstrated. A CIPI that uses a lactate dehydrogenase level of 500 IU/L worked well for estimating the prognosis. We recommend AHSCT at first complete remission for relapsed cases, and it should also be taken into consideration for patients with high prognostic scores at diagnosis.

Abdomen/pelvis computed tomography in staging of pediatric Hodgkin Lymphoma: is it always necessary?

The purpose of the study was to determine if abdomen/pelvis computed tomography (CT) can be safety omitted in the initial staging of a subgroup of children affected by Hodgkin Lymphoma (HL). Every participating center of A.I.E.O.P (Associazione Italiana di Ematologia ed Oncologia Pediatrica) sent local staging reports of 18F‐fluorodeoxyglucose positron emission tomography (PET) and abdominal ultrasound (US) along with digital images of staging abdomen/pelvis CT to the investigation center where the CT scans were evaluated by an experienced pediatric radiologist. The local radiologist who performed the US was unaware of local CT and PET reports (both carried out after US), and the reviewer radiologist examining the CT images was unaware of local US, PET and CT reports. A new abdominal staging of 123 patients performed on the basis of local US report, local PET report, and centralized CT report was then compared to a simpler staging based on local US and PET. No additional lesion was discovered by CT in patients with abdomen/pelvis negativity in both US and PET or isolated spleen positivity in US (or US and PET), and so it seems that in the initial staging, abdomen/pelvis CT can be safety omitted in about 1/2 to 2/3 of children diagnosed with HL.

No survival benefit associated with routine surveillance imaging for Hodgkin lymphoma in first remission: a Danish-Swedish population-based observational study

The use of routine imaging for patients with classical Hodgkin lymphoma (HL) in complete remission (CR) is controversial. In a population-based study, we examined the post-remission survival of Danish and Swedish HL patients for whom follow-up practices were different. Follow-up in Denmark included routine imaging, usually for a minimum of 2 years, whereas clinical follow-up without routine imaging was standard in Sweden. A total of 317 Danish and 454 Swedish comparable HL patients aged 18-65 years, diagnosed in the period 2007-2012 and having achieved CR following ABVD (doxorubicin, bleomycin, vinblastine, dacarbazine)/BEACOPP (bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, prednisone) therapy, were included in the study. The cumulative progression rates in the first 2 years were 4% (95% confidence interval [CI] 1-7) for patients with stage I-II disease vs. 12% (95% CI 6-18) for patients with stage III-IV disease. An imaging-based follow-up practice was not associated with a better post-remission survival in general (P = 0·2) or in stage-specific subgroups (P = 0·5 for I-II and P = 0·4 for III-IV). Age ≥45 years was the only independent adverse prognostic factor for survival. In conclusion, relapse of HL patients with CR is infrequent and systematic use of routine imaging in these patients does not improve post-remission survival. The present study supports clinical follow-up without routine imaging, as encouraged by the recent Lugano classification.

Role of Surveillance Imaging in Patients With Peripheral T-Cell Lymphoma

INTRODUCTION

The role of surveillance imaging (SI) in patients with peripheral T-cell lymphoma (PTCL) in first complete remission (CR1) is unclear.

MATERIALS AND METHODS

Patients with PTCL were identified through prospectively maintained T-cell lymphoma databases from the National Cancer Centre Singapore/Singapore General Hospital and Weill-Cornell Medical College after institutional review board approval. Patients with leukemia or indolent, composite, and cutaneous lymphomas were excluded. The patients' medical records were retrospectively reviewed to determine the frequency and type of SI used. Of those with relapse, the method of relapse detection and data on symptoms, signs, and elevated lactate dehydrogenase LDH were extracted.

RESULTS

A total of 338 patients were included in the present study. In the first year after achieving CR1, patients had an average of 1.2 and a median of 1 SI performed (range, 0-4). In the second year after achieving CR1, they had an average of 0.78 and a median of 1 SI performed (range, 0-4). Of the 135 patients who achieved CR1, 61 (45%) developed a relapse. Relapses were detected before SI in 48 (84%), and 9 patients had relapses detected during routine SI. Of the 9 patients whose relapses were detected during planned SI, only 3 did not have any symptoms or signs suggestive of relapsed disease. Of these 3 patients, 2 had angioimmunoblastic T-cell lymphoma and 1 had natural killer/T-cell lymphoma.

CONCLUSION

Most PTCL relapses were detected before planned SI, and most patients had symptoms with relapse. Only 3 patients (5.2%) were completely asymptomatic at relapse, suggesting a limited utility of routine imaging for detecting PTCL relapses.

Patterns of diagnostic imaging and associated radiation exposure among long-term survivors of young adult cancer: a population-based cohort study

BACKGROUND

Survivors of young adult malignancies are at risk of accumulated exposures to radiation from repetitive diagnostic imaging. We designed a population-based cohort study to describe patterns of diagnostic imaging and cumulative diagnostic radiation exposure among survivors of young adult cancer during a survivorship time period where surveillance imaging is not typically warranted.

METHODS

Young adults aged 20-44 diagnosed with invasive malignancy in Ontario from 1992-1999 who lived at least 5 years from diagnosis were identified using the Ontario Cancer Registry and matched 5 to 1 to randomly selected cancer-free persons. We determined receipt of 5 modalities of diagnostic imaging and associated radiation dose received by survivors and controls from years 5-15 after diagnosis or matched referent date through administrative data. Matched pairs were censored six months prior to evidence of recurrence.

RESULTS

20,911 survivors and 104,524 controls had a median of 13.5 years observation. Survivors received all modalities of diagnostic imaging at significantly higher rates than controls. Survivors received CT at a 3.49-fold higher rate (95% Confidence Interval [CI]:3.37, 3.62) than controls in years 5 to 15 after diagnosis. Survivors received a mean radiation dose of 26 miliSieverts solely from diagnostic imaging in the same time period, a 4.57-fold higher dose than matched controls (95% CI: 4.39, 4.81).

CONCLUSIONS

Long-term survivors of young adult cancer have a markedly higher rate of diagnostic imaging over time than matched controls, imaging associated with substantial radiation exposure, during a time period when surveillance is not routinely recommended.

Patterns and utility of routine surveillance in high grade endometrial cancer

OBJECTIVE

To evaluate surveillance methods and their utility in detecting recurrence of disease in a high grade endometrial cancer population.

METHODS

We performed a multi-institutional retrospective chart review of women diagnosed with high grade endometrial cancer between the years 2000 and 2011. Surveillance data was abstracted and analyzed. Surveillance method leading to detection of recurrence was identified and compared by stage of disease and site of recurrence.

RESULTS

Two hundred and fifty-four patients met the criteria for inclusion. Vaginal cytology was performed in the majority of early stage patients, but was utilized less in advanced stage patients. CA-125 and CT imaging were used more frequently in advanced stage patients compared to early stage. Thirty-six percent of patients experienced a recurrence and the majority of initial recurrences (76%) had a distant component. Modalities that detected cancer recurrences were: symptoms (56%), physical exam (18%), surveillance CT (15%), CA-125 (10%), and vaginal cytology (1%). All local recurrences were detected by symptoms or physical exam findings. While the majority of loco-regional and distant recurrences (68%) were detected by symptoms or physical exam, 28% were detected by surveillance CT scan or CA 125. One loco-regional recurrence was identified by vaginal cytology but no recurrences with a distant component detected by this modality.

CONCLUSIONS

Symptoms and physical examination identify the majority of high grade endometrial cancer recurrences, while vaginal cytology is the least likely surveillance modality to identify a recurrence. The role of CT and CA-125 surveillance outside of a clinical trial needs to be further reviewed.

Value of 18F-FDG PET and PET/CT for evaluation of pediatric malignancies

Successful management of solid tumors in children requires imaging tests for accurate disease detection, characterization, and treatment monitoring. Technologic developments aim toward the creation of integrated imaging approaches that provide a comprehensive diagnosis with a single visit. These integrated diagnostic tests not only are convenient for young patients but also save direct and indirect health-care costs by streamlining procedures, minimizing hospitalizations, and minimizing lost school or work time for children and their parents. (18)F-FDG PET/CT is a highly sensitive and specific imaging modality for whole-body evaluation of pediatric malignancies. However, recent concerns about ionizing radiation exposure have led to a search for alternative imaging methods, such as whole-body MR imaging and PET/MR. As we develop new approaches for tumor staging, it is important to understand current benchmarks. This review article will synthesize the current literature on (18)F-FDG PET/CT for tumor staging in children, summarizing questions that have been solved and providing an outlook on unsolved avenues.

Relapse surveillance in AFP-positive hepatoblastoma: re-evaluating the role of imaging

BACKGROUND

Children with hepatoblastoma routinely undergo repetitive surveillance imaging, with CT scans for several years after therapy, increasing the risk of radiation-induced cancer.

OBJECTIVE

The purpose of this study was to determine the utility of surveillance CT scans compared to serum alpha-fetoprotein (AFP) levels for the detection of hepatoblastoma relapse.

MATERIALS AND METHODS

This was a retrospective study of all children diagnosed with AFP-positive hepatoblastoma from 2001 to 2011 at a single institution.

RESULTS

Twenty-six children with hepatoblastoma were identified, with a mean age at diagnosis of 2 years 4 months (range 3 months to 11 years). Mean AFP level at diagnosis was 132,732 ng/ml (range 172.8-572,613 ng/ml). Five of the 26 children had hepatoblastoma relapse. A total of 105 imaging exams were performed following completion of therapy; 88 (84%) CT, 8 (8%) MRI, 5 (5%) US and 4 (4%) FDG PET/CT exams. A total of 288 alpha-fetoprotein levels were drawn, with a mean of 11 per child. The AFP level was elevated in all recurrences and no relapses were detected by imaging before AFP elevation. Two false-positive AFP levels and 15 false-positive imaging exams were detected. AFP elevation was found to be significantly more specific than PET/CT and CT imaging at detecting relapse.

CONCLUSION

We recommend using serial serum AFP levels as the preferred method of surveillance in children with AFP-positive hepatoblastoma, reserving imaging for the early postoperative period, for children at high risk of relapse, and for determination of the anatomical site of clinically suspected recurrence. Given the small size of this preliminary study, validation in a larger patient population is warranted.

Update on pediatric leukemia and lymphoma imaging

Together, leukemia and lymphoma account for half of all childhood malignancies. Leukemia and lymphoma arise from similar cell lines and can have overlapping imaging features; however, the clinical presentation, imaging strategies, and treatment protocols can vary substantially based on the specific subtype. Although imaging does not play a central role in staging or monitoring disease in childhood leukemia, findings on imaging may be the first indication of the diagnosis. Advanced imaging, especially positron emission tomography/computed tomography, has moved to the forefront of staging and treatment response evaluation in Hodgkin's disease and non-Hodgkin's lymphoma. Imaging also plays a key role in evaluating the myriad of treatment complications that are commonly seen with chemotherapy and associated neutropenia. Future efforts will be largely focused on decreasing radiation exposure to these children, utilizing reduced or radiation-free modalities, such as positron emission tomography/magnetic resonance and diffusion-weighted whole-body imaging with background suppression, as well as refining surveillance imaging strategies. The purpose of this article is to briefly review the classification of pediatric leukemia and lymphoma, illustrate common imaging findings at presentation throughout the body, describe staging and therapeutic response evaluation, and show a spectrum of commonly encountered complications of treatment.

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.

Limited utility of routine surveillance imaging for classical Hodgkin lymphoma patients in first complete remission

BACKGROUND

The objective of this study was to compare the outcomes of patients with classical Hodgkin lymphoma (cHL) who achieved complete remission with frontline therapy and then underwent either clinical surveillance or routine surveillance imaging.

METHODS

In total, 241 patients who were newly diagnosed with cHL between January 2000 and December 2010 at 3 participating tertiary care centers and achieved complete remission after first-line therapy were retrospectively analyzed. Of these, there were 174 patients in the routine surveillance imaging group and 67 patients in the clinical surveillance group, based on the intended mode of surveillance. In the routine surveillance imaging group, the intended plan of surveillance included computed tomography and/or positron emission tomography scans; whereas, in the clinical surveillance group, the intended plan of surveillance was clinical examination and laboratory studies, and scans were obtained only to evaluate concerning signs or symptoms. Baseline patient characteristics, prognostic features, treatment records, and outcomes were collected. The primary objective was to compare overall survival for patients in both groups. For secondary objectives, we compared the success of second-line therapy and estimated the costs of imaging for each group.

RESULTS

After 5 years of follow-up, the overall survival rate was 97% (95% confidence interval, 92%-99%) in the routine surveillance imaging group and 96% (95% confidence interval, 87%-99%) in the clinical surveillance group (P = .41). There were few relapses in each group, and all patients who relapsed in both groups achieved complete remission with second-line therapy. The charges associated with routine surveillance imaging were significantly higher than those for the clinical surveillance strategy, with no apparent clinical benefit.

CONCLUSIONS

Clinical surveillance was not inferior to routine surveillance imaging in patients with cHL who achieved complete remission with frontline therapy. Routine surveillance imaging was associated with significantly increased estimated imaging charges.

Pediatric Burkitt's lymphoma and diffuse B-cell lymphoma: are surveillance scans required?

Outcomes in pediatric B-Non-Hodgkin Lymphoma (B NHL) have improved with intensive chemotherapy protocols, with long-term survival now over 80%. However, long-term adverse effects of therapy and poor outcomes for patients who relapse remain challenges. In this study, we aimed to evaluate the potential risks and benefits of routine relapse surveillance imaging after the completion of therapy. We reviewed 44 B NHL patients diagnosed and treated at Texas Children's Cancer Center in the period between 2000 to 2011. All cross-sectional diagnostic imaging examinations performed for disease assessment after completion of chemotherapy were reviewed and cumulative radiation dosage from these examinations and the frequency of relapse detection by these examinations were recorded. Only 3 patients of the 44 relapsed (6.8%), though none of the relapses were initially diagnosed by computed tomography (CT) or fludeoxyglucose positron emission tomography (FDG-PET) scans. Median effective dose of ionizing radiation per patient was 40.3 mSv with an average of 49.1 mSv (range 0-276 mSv). This single-institution study highlights the low relapse rate in pediatric B-NHL with complete response at the end of therapy, the low sensitivity of early detection of relapse with surveillance CT or FDG-PET imaging, and the costs and potential increased risk of secondary malignancies from cumulative radiation exposure from surveillance imaging. We propose that routine surveillance CT or FDG-PET scans for these patients may not be necessary.

Pediatric oncology surveillance imaging: two recommendations. Abandon CT scanning, and randomize to imaging or solely clinical follow-up

Radiologic assessments in children with cancer provide information crucial to patient management at diagnosis and during follow-up. Many studies have now been published, however, questioning the usefulness of off-therapy surveillance imaging. There is growing concern regarding the hazards from diagnostic irradiation to young patients, most notably from CT scanning. In this paper we advocate abandoning repeated CT surveillance in young patients with a previously treated solid malignancy not arising in the central nervous system. In addition, randomized studies of imaging surveillance versus no imaging surveillance strategies are needed to determine whether earlier detection of recurrence results in improved survival.

Surveillance imaging for lymphoma: pros and cons

There is no international consensus on the optimal frequency or duration of computed tomography or positron emission tomography scanning for surveillance in patients who achieve complete remission after initial therapy for lymphoma. Although some clinical practice guidelines suggest periodic imaging is reasonable, others suggest little or no benefit to this practice. From a theoretical perspective, the frequency and duration of surveillance imaging is largely dependent upon the lymphoma subtype. Aggressive lymphomas with a fast growth rate will require surveillance more frequently and for a shorter duration compared to the indolent lymphomas. Historically, relapse has been detected in a majority of patients based upon clinically evident signs and symptoms. Currently, no study has demonstrated an overall survival difference for patients with relapse detected by imaging as opposed to clinical evaluation, although one study did demonstrate a lower second-line International Prognostic Index in patients with relapse detected by surveillance imaging. Enthusiasm for this finding has been tempered by recent studies highlighting the potential long-term risk of secondary malignancies because of ionizing radiation exposure from diagnostic imaging. These factors along with the significant costs associated with diagnostic imaging have contributed to an ongoing debate regarding the relative costs, risks, and benefits of radiographic surveillance. Herein we present perspectives for and against routine surveillance imaging in an effort to facilitate a better understanding of the issues relevant to what is ultimately a clinical decision made by an oncologist and his or her patient.

Relapse after treatment of pediatric Hodgkin lymphoma: outcome and role of surveillance after end of therapy

BACKGROUND

The outcome of treatment for pediatric Hodgkin lymphoma (HL) is excellent using chemotherapy and radiation. However, a minority of patients will relapse after treatment, but additional therapy achieves durable second remission in many cases. The optimal surveillance strategy after modern therapy for HL has not been well defined.

PROCEDURES

We reviewed the outcomes of pediatric patients with HL treated between 1990 and 2006 to determine the primary event that led to the detection of relapse. We determined the probability of relapse detection by routine follow-up procedures, including history, physical examination, laboratory tests, and imaging, and determined the impact of each of these screening methods on the likelihood of survival after relapse.

RESULTS

Relapse occurred in 64 of 402 evaluable patients (15.9%) at a median of 1.7 years from the time of diagnosis. The majority of relapses (60%) were diagnosed at a routine visit, and patient complaint was the most common initial finding that led to a diagnosis of relapse (47% of relapses). An abnormal finding on physical examination was the primary event in another 17% of relapses, and imaging abnormalities led to the diagnosis in the remaining 36%. Laboratory abnormalities were never the primary finding. The method of detection of relapse and timing (whether detected at a routine visit or an extra visit) did not impact survival.

CONCLUSIONS

In pediatric HL, most relapses are identified through history and physical examination. Frequent imaging of asymptomatic patients does not appear to impact survival and is probably not warranted.

Postresection surveillance for pancreatic cancer performance status, imaging, and serum markers

Approximately 15% of patients with a diagnosis of pancreatic adenocarcinoma are candidates for potentially curative surgery. However, most patients who undergo such surgery will die from recurrent disease, most within the first few years, whereas nearly all succumb by 5 to 7 years from diagnosis. Currently, there is a lack of high-level evidence to guide consensus recommendations as to the optimal surveillance strategy after resection. There is considerable variability in clinical practice, ranging from frequent clinical follow-up, with serial Ca 19-9 measurement and routine computed tomographic imaging on a 3- to 6-monthly basis, to a practice of no routine serum or imaging follow-up after surgery. In most part, this divergence in practice reflects a lack of data to define optimal practice. The argument in favor of limited surveillance presumably stems from the relatively uniform poor outcomes after recurrence and the absence of evidence indicating that early detection of local, regional, or metastatic recurrence improves outcomes. However, recent advancements in the treatment of metastatic disease offer hope that earlier detection and initiation of treatment for recurrent disease may positively impact clinical outcomes and at least urges review of the topic. One advantage to the development of defined guidelines would be greater consistency in the setting of both routine clinical follow-up and follow-up after adjuvant therapy on trial.

Imaging in childhood cancer: a Society for Pediatric Radiology and Children's Oncology Group Joint Task Force report

Contemporary medical imaging is a cornerstone of care for children with cancer. As 5-year survival rates for children with cancer exceed 80%, imaging technologies have evolved in parallel to include a wide array of modalities. Here, we overview the risks and benefits associated with commonly used imaging modalities and survey the current landscape of medical imaging for children with cancer. We find evidence-based imaging guidelines to assist in protocol development and to guide decision-making for optimal patient care are often lacking. The substantial variation in protocol-based recommendations for imaging both during and following therapy may hinder optimal clinical research and clinical care for children with cancer.

Determining response and recurrence in pediatric B-cell lymphomas of the bone

BACKGROUND

Primary lymphomas of the bone are rare in children, but have an excellent response to therapy. Evaluating patients for remission and recurrence can be challenging given the difficulties of distinguishing healing bone from residual tumor on imaging. A review of imaging in patients treated for primary bone lymphoma (PBL) in one center was performed in an effort to determine best practice.

METHODS

Twelve cases of PBL diagnosed and treated from 2000 to 2011 at the Children's Hospital of Philadelphia were identified. Information about presentation, histology, imaging, treatment, and outcomes was collected.

RESULTS

There were no recurrences of the primary bone tumor after therapy. One patient developed therapy-related AML. Although PET-avid lesions usually fell below a SUVmax of 3 within 3 months, low-level SUVmax lesions often remained up to 12 months post-therapy. At no point during therapy did radiographs, MRI, bone scans or CT of bones normalize, most remaining abnormal for several months to years. Patients were exposed to significant ionizing radiation, with estimated levels ranging from 9.5 to 183.1 mSv per patient. Over 10% of scans had incidental findings, which led to 17 extra imaging studies and 4 biopsies, but no clinically significant outcomes.

CONCLUSIONS

In our cohort, frequent imaging did not affect or improve outcome. Due to the low risk of relapse and high rate of repeated imaging for incidental findings, minimization of post-therapy imaging should be considered. This modification in practice will significantly reduce radiation exposure, as well as potentially decrease parent and patient anxiety.