Unifying the predictive value of pretransplant FDG PET in patients with lymphoma: a review and meta-analysis of published trials

An updated meta-analysis of prostatic arterial embolization versus transurethral resection of the prostate in the treatment of benign prostatic hyperplasia

OBJECTIVE

To investigate whether prostatic arterial embolization (PAE) could be recommended as a routine therapy for benign prostatic hyperplasia (BPH), we conducted an updated meta-analysis to assess the efficacy and safety of PAE compared with transurethral resection of the prostate (TURP).

METHODS

Systematic literature retrieval by searching data from Web of science, Pubmed, Embase, Cochrane Library, ClinicalTrial.gov, CNKI, Wanfang and VIP databases was carried out to identify all related trials from the inception dates to June 2019. We also conducted subgroup analyses depending on the kind of study design, kind of PAE and kind of TURP.

RESULTS

Nine studies comparing PAE with TURP involving a total of 860 BPH patients were selected. Postoperative reduced IPSS score (MD 2.50; 95% CI 0.78-4.21; P = 0.004), postoperative reduced QOL score (MD 0.40; 95% CI 0.09-0.71; P = 0.01), postoperative reduced PV (MD 8.59; 95% CI 4.74-12.44; P < 0.00001) and postoperative increased Q_max (MD 2.54; 95% CI 1.02-4.05; P = 0.001) were better in TURP than in PAE; however, PAE was associated with lower sexual dysfunction rate (OR 0.24; 95% CI 0.15-0.39; P < 0.00001) compared with TURP. Meanwhile, no significant difference in postoperative reduced PVR (MD 0.46; 95% CI - 2.08 to 3.00; P = 0.72) and complication (OR 0.57; 95% CI 0.21-1.55; P = 0.27) between PAE and TURP group was demonstrated.

CONCLUSION

PAE was inferior to TURP in the improvement of postoperative IPSS, QOL, PV, Q_max and TURP still remained the gold standard. However, PAE may be a valuable alternative to TURP in the treatment of BPH patients who refuse surgery or with surgery contraindication.

[Prognostic significance of (18)F-fluorodeoxyglucose positron emission tomography in patients with diffuse large B cell lymphoma undergoing autologous stem cell transplantation]

Objective: To evaluate the prognostic value of (18)F-fluorodeoxyglucose positron emission tomography (PET)/computed tomography (CT) in patients with diffuse large B cell lymphoma (DLBCL) undergoing autologous hematopoietic stem cell transplantation (auto-HSCT). Methods: Forty-eight patients with DLBCL treated at Peking University Cancer Hospital between November 2010 and December 2014 were assessed. All patients underwent PET/CT scanning prior to or after auto-HSCT. Correlation analysis was done based upon patients characteristics, PET/CT scan results and survival. Results: ①Among 48 patients, 27 was male, 21 female, median age was 43 (17-59) years old. ② Patients with negative pre-auto-HSCT PET/CT assessment demonstrated significantly better 3-year progression free survival (PFS) (87.1% vs 53.3%, χ(2)=7.02, P=0.019) and overall survival (OS) (90.3% vs 60.0%, χ(2)=6.51,P=0.022) than patients with positive pre-auto-HSCT PET/CT assessment. Three-year PFS (94.1% vs 30.0%, χ(2)=22.75, P=0.001) and OS (97.1% vs 40.0%, χ(2)=21.09, P=0.002) were also significantly different between patients with negative and positive post-auto-HSCT PET/CT assessment. ③ Multivariate analysis indicated a significant association of PFS (HR=13.176, P=0.005) and OS (HR=20.221, P=0.007) with post-auto-HSCT PET/CT assessment. Number of prior treatment regimens was associated with PFS (HR=10.039, P=0.040). ④ Harrell's C index revealed that the value of combined use of number of prior treatment regimens and post-auto-HSCT PET/CT assessment was superior to either one used alone in PFS (Harrell's C values were 0.976, 0.869 and 0.927 in combined use, number of prior treatment regimens and post-auto-HSCT PET/CT assessment, respectively), and the combined use of ECOG performance status and post-auto-HSCT PET/CT assessment significantly increased the Harrell's C index in OS (Harrell's C values were 0.973, 0.711 and 0.919 in combined use, ECOG performance status and post-auto-HSCT PET/CT assessment, respectively). Conclusions: Post-auto-HSCT PET/CT assessment is the main predictor of outcomes in DLBCL patients receiving auto-HSCT. Combined use of post-auto-HSCT PET/CT assessment and number of prior treatment regimens and ECOG performance status is a better prognostic tool in patients with DLBCL undergoing transplantation.

Haploidentical Transplants with Post-Transplant Cyclophosphamide for Relapsed or Refractory Hodgkin Lymphoma: The Role of Comorbidity Index and Pretransplant Positron Emission Tomography

Disease relapse remains an unmet medical need for patients with Hodgkin lymphoma (HL) receiving an allogeneic hematopoietic cell transplantation (HCT). With the aim of identifying patients at high risk for post-transplant relapse, we retrospectively reviewed 41 HL patients who had received haploidentical (haplo) nonmyeloablative (NMA) HCT with high dose post-transplant cyclophosphamide (PT-Cy) for graft-versus-host (GVHD) prophylaxis. Primary refractory disease, relapse within 6 months from autologous stem cell transplantation, age, pretransplant chemotherapy, HCT comorbidity index (HCT-CI), sex mismatch, tumor burden and pretransplant fluorodeoxyglucose positron emission tomography (FDG-PET) status, assessed by Deauville score, were analyzed as variables influencing outcomes. All but 1 patient engrafted: median time to neutrophil and platelet recovery was 15 (interquartile range, 13 to 23) days and 19 (interquartile range, 12 to 28) days, respectively. Cumulative incidence of severe (grade III to IV) acute graft-versus-host disease (GVHD) and 3-year moderate-severe chronic GVHD was 2.4% and 11.8%, respectively. The 3-year overall (OS), progression free (PFS), and graft relapse-free survival (GRFS) were 75.6%, 43.9%, and 39%, respectively. On multivariate analysis, 3-year OS was significantly worse in patients with HCT-CI ≥3 (hazard ratio [HR], 5.0; 95% confidence interval [CI], 1.1 to 21.8; P = .03). Three-year relapse rate, 3-year PFS, and 3-year GRFS were significantly worse in patients with HCT-CI ≥3 (HR, 3.5; 95% CI, 1.3 to 9.3; P = .01; HR, 3.3; 95% CI, 1.2 to 9.0; P = .02; and HR, 4.2; 95% CI, 1.7 to 9.9; P = .001, respectively) and in patients with a Deauville score ≥4 on pretransplant FDG-PET (HR, 4.4; 95% CI, 1.6-12.4; P = .005, HR, 3.8; 95% CI, 1.5 to 9.7; P = .005; and 3.2; 95% CI, 1.3 to 7.9; P = .01, respectively). On univariate analysis, 3-year NRM was significantly worse only in patients with a HCT-CI ≥3 (HR, 17.6; 95% CI, 1.4 to 221.0). Among relapsed or refractory HL patients undergoing haplo NMA HCT with PT-Cy, pretransplant FDG-PET with a Deauville score ≥4 and HCT-CI ≥3 identified patients at high risk of relapse. Moreover, an HCT-CI ≥3 was associated with higher NRM and lower OS.

Yttrium-90 ibritumomab tiuxetan (Zevalin) followed by BEAM (Z-BEAM) conditioning regimen and autologous stem cell transplantation (ASCT) in relapsed or refractory high-risk B-cell non-Hodgkin lymphoma (NHL): a single institution Italian experience

Chemo-refractory NHL has a very poor outcome; the addiction of RIT to salvage regiment pre ASCT had recently demonstrated promising results.We performed a retrospective sequential study to determine the feasibility of standard Zevalin with BEAM in high-risk relapse/refractory NHL. A matched cohort analysis with a group treated with standard BEAM without Zevalin was performed as secondary endpoint. Between October 2006 and January 2013, 37 NHL patients at high risk for progression or early (< 1 year) or multiple relapses were treated with Z-BEAM and ASCT after R-DHAP or R-ICE as salvage therapy. Clinical characteristics were 19 refractory and 18 early or multiple relapse; 16 patients received 1, and 21 had 2 or more previous rituximab-containing chemotherapy. At the end of treatment, response was CR 22 (59%), PR 10 (27%), PD 4 (11%), and toxic death (TD) 1 (3%). With a median follow up of 61 months, 3-year PFS was 61% and OS 61%. Fifteen patients died, 12 of lymphoma. Comparison with 21 treated with BEAM alone showed a numerical higher 3-yr PFS rate in favor of Z-BEAM but not statistically significant (57 vs 48%). With the limitation of the small sample subgroup analysis, a significant benefit was observed in relapsed patients for PFS (78% Z-BEAM vs 22% BEAM p = 0.016) and OS (83% Z-BEAM vs 22% BEAM p = 0.001). In relapsed/refractory high-risk NHL, Z-BEAM+ASCT is able to achieve a good ORR. Three-year PFS is promising for early relapsed patients but is not satisfactory for those with refractory disease.

Prognostic value of pre- and post-transplantation 18F-fluorodeoxyglucose positron emission tomography results in non-Hodgkin lymphoma patients receiving autologous stem cell transplantation

Objective

High-dose chemotherapy (HDC) followed by autologous stem cell transplantation (ASCT) is the standard of care in the upfront or relapsed/refractory setting in some patients with non-Hodgkin lymphoma (NHL). However, a proportion of patients do not respond to ASCT. ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) has been widely used for staging, response evaluation, and prognosis prediction. Here, we investigated the prognostic role of PET/CT in NHL patients before and after ASCT.

Methods

A retrospective study was conducted at Peking University Cancer Hospital. All NHL patients who underwent ASCT between March 2010 and July 2016 were identified. Patients who had PET/CT scan before and after ASCT were included. Deauville criteria (5-point scale) were used to interpret PET scans. Univariate and multivariate survival analyses were performed using Cox regression. The predictive value of PET scanning was estimated by comparing the area under the receiver operating characteristic (ROC) curve.

Results

In total, 79 patients were enrolled in this study. In univariate analysis, pre- and post-ASCT PET result was identified as prognostic factors for 3-year progression-free survival (PFS) and overall survival (OS). Patients with negative pre-ASCT PET result demonstrated significantly better PFS (84.2% vs. 54.2%) and OS (89.2% vs. 63.6%) than patients with positive pre-ASCT PET result. PFS (91.6% vs. 25.3%) and OS (96.5% vs. 36.8%) were also significantly different between patients with negative and positive post-ASCT PET result. Multivariate analysis also showed a significant association between survival and post-ASCT PET result. ROC analysis revealed that the predictive value of post-ASCT PET result was superior to that of pre-ASCT PET result alone. Combined pre- and post-ASCT PET result is better for predicting outcomes in patients with NHL receiving transplantation. Deauville criteria score >3 was identified as the best cutoff value for post-ASCT PET.

Conclusions

Post-ASCT PET result was more important than pre-ASCT PET result in predicting outcomes for NHL patients who underwent ASCT. The prognostic significance can be improved when combining pre-ASCT PET result with post-ASCT PET result. Deauville criteria can be used for interpreting PET scans in this scenario.

A Systematic Review and Meta-analysis of Intraluminal Brachytherapy Versus Stent Alone in the Treatment of Malignant Obstructive Jaundice

OBJECTIVES

To evaluate therapeutic outcomes of intraluminal brachytherapy (ILBT) for malignant obstructive jaundice (MOJ) against stent alone.

METHODS

The PubMed, EMBASE, Cochrane Library, CNKI, Wan Fang, VIP and ClinicalTrials.gov databases were searched for all relevant comparative studies from the earliest available date up to 1 May 2017. Subgroup analyses were performed according to the type of study design and type of stent.

RESULTS

Twelve studies that compared ILBT versus stent alone were eligible. A total of 641 participants with MOJ were included in our meta-analysis. A total of 340 participants were treated with intraluminal brachytherapy (ILBT); the other 301 participants were treated with biliary stent alone (stent group). ILBT was associated with lower risk of stent occlusion (OR 0.19; 95% CI 0.13-0.28; P < 0.00001) and better mean survival (MD = 3.15; 95% CI 2.64-3.66; P < 0.00001) compared with stent alone. However, the two groups were similar in number of complications (OR 0.84; 95% CI 0.45-1.56; P = 0.578), post-treatment reduced level of total bilirubin (TBIL) (MD = 22.71; 95% CI - 7.24-52.65; P = 0.14), post-treatment reduced level of direct bilirubin (DBIL) (MD = - 3.67; 95% CI - 14.09-6.75; P = 0.49), post-treatment reduced level of alanine aminotransferase (ALT) (MD = 21.09; 95% CI - 5.09-47.28; P = 0.11) and post-treatment reduced level of aspartate aminotransferase (AST) (MD = 20.86; 95% CI - 45.86-87.58; P = 0.54).

CONCLUSIONS

ILBT was significantly superior to stent alone in terms of stent occlusion and mean survival. Meanwhile, ILBT had comparable outcomes to stent alone in terms of complications and post-treatment reduced levels of TBIL, DBIL, ALT and AST. Therefore, ILBT may be considered a preferable technique for MOJ.

Positron Emission Tomography-Based Assessment of Metabolic Tumor Volume Predicts Survival after Autologous Hematopoietic Cell Transplantation for Hodgkin Lymphoma

Autologous hematopoietic cell transplantation (AHCT) is curative for 60% of patients with relapsed or refractory Hodgkin lymphoma (R/R HL). A more precise assessment of the depth of remission before AHCT may help to identify patients likely to benefit from AHCT. We aimed to determine whether positron emission tomography (PET)-based quantitative parameters of total metabolic tumor volume (TMTV), total lesion glycolysis (TLG), and maximal standardized uptake volume (SUV_max) measured before AHCT predict progression-free survival (PFS) after transplant. Pretransplant PET/computed tomography images of 96 consecutive patients with R/R HL were analyzed. Median TMTV, TLG, and SUV_max were 7.97 cm³ (range, 1.3 to 102.1), 23.7 (range, 4.0 to 813.1), and 5.23 (range, 2.7 to 23.2). Two-year PFS in patients with high TMTV (TMTVhigh; more than median; n = 17) was only 12% (95% CI, 1% to 38%) compared with 53% (95% CI, 28% to 73%; P = .05) in patients with TMTVlow (lower or equal to median; n = 17) and 63% (95% CI, 50% to 74%) in 61 patients with no metabolically active tumor (TMTV0; P > .01). In concordance, high TLG (>19) and SUV_max (>4.9) predicted inferior 2-year PFS. In multivariate analysis patients with TMTVhigh had a 3.5-fold higher risk of treatment failure compared with TMTV0/TMTVlow (HR, 3.49; 95% CI, 1.75 to 6.93; P < .01). Deauville (D)-scores of 4 to 5 before AHCT predicted worse PFS compared with D-scores of 1 to 3 (HR, 3.7; 95% CI, 1.92 to 7.28; P < .01). Yet, TMTV and D-scores were disconcordant in 12 subjects; 9 patients in the D4 group with TMTVlow had 2-year PFS of 44% (95% CI, 14% to 72%), which was 2-fold higher than predicted by D4 score. In conclusion, in patients with R/R HL and PET-positive residual disease, TMTVhigh can identify very poor AHCT responders. Patients with TMTVlow, TLG, and SUV_max before AHCT have similar outcomes to those without metabolically active disease.

FDG PET/CT in cancer: comparison of actual use with literature-based recommendations

Purpose

The Region of Southern Denmark (RSD), covering 1.2 of Denmark’s 5.6 million inhabitants, established a task force to (1) retrieve literature evidence for the clinical use of positron emission tomography (PET)/CT and provide consequent recommendations and further to (2) compare the actual use of PET/CT in the RSD with these recommendations. This article summarizes the results.

Methods

A Work Group appointed a professional Subgroup which made Clinician Groups conduct literature reviews on six selected cancers responsible for 5,768 (62.6 %) of 9,213 PET/CT scans in the RSD in 2012. Rapid Evidence Assessment was applied, using the methodology of systematic reviews with predefined limitations to search PubMed, Embase and the Cochrane Library for articles published in English/Danish/Swedish/Norwegian since 2002. PICO questions were defined, data recorded and quality appraised and rated with regard to strength and evidence level. Consequent recommendations for applications of PET/CT were established. The actual use of PET/CT was compared with these, where grades A and B indicated “established” and “useful” and grades C and D “potentially useful” and “non-recommendable” indications, respectively.

Results

Of 11,729 citations, 1,729 were considered for review, and 204 were included. The evidence suggested usefulness of PET/CT in lung, lymphoma, melanoma, head and neck, and colorectal cancers, whereas evidence was sparse in gynaecological cancers. The agreement between actual use of PET/CT and literature-based recommendations was high in the first five mentioned cancers in that 96.2 % of scans were made for grade A or B indications versus only 22.2 % in gynaecological cancers.

Conclusion

Evidence-based usefulness was reported in five of six selected cancers; evidence was sparse in the sixth, gynaecological cancers. Actual use of PET/CT agreed well with recommendations.

Electronic supplementary material

The online version of this article (doi:10.1007/s00259-015-3217-0) contains supplementary material, which is available to authorized users.

Impact of Pretransplantation (18)F-fluorodeoxy Glucose-Positron Emission Tomography Status on Outcomes after Allogeneic Hematopoietic Cell Transplantation for Non-Hodgkin Lymphoma

Assessment with (18)F-fluorodeoxy glucose (FDG)-positron emission tomography (PET) before hematopoietic cell transplantation (HCT) for lymphoma may be prognostic for outcomes. Patients with chemotherapy-sensitive non-Hodgkin lymphoma (NHL) undergoing allogeneic HCT reported to the Center of International Blood and Marrow Transplantation Registry between 2007 and 2012 were included. Pre-HCT PET status (positive versus negative) was determined by the reporting transplantation centers. We analyzed 336 patients; median age was 55 years and 60% were males. Follicular lymphoma (n = 104) was more common than large cell (n = 85), mantle cell (n = 69), and mature natural killer or T cell lymphoma (n = 78); two thirds of the cohort received reduced-intensity conditioning; one half had unrelated donor grafts. Patients underwent PET scanning a median of 1 month (range, .07 to 2.83 months) before HCT; 159 were PET positive and 177 were PET negative. At 3 years, relapse/progression, progression-free survival (PFS), and overall survival (OS) in PET-positive versus PET-negative groups were 40% versus 26%; P = .007; 43% versus 47%; P = .47; and 58% versus 60%; P = .73, respectively. On multivariate analysis, a positive pretransplantation PET was associated with an increased risk of relapse/progression (risk ratio [RR], 1.86; P = .001) but was not associated with increased mortality (RR, 1.29, 95% confidence interval [CI], .96 to 1.7; P = .08), therapy failure (RR, 1.32; 95% CI, .95 to 1.84; P = .10), or nonrelapse mortality (RR, .75; 95% CI, .48 to 1.18; P = .22). PET status conferred no influence on graft-versus-host disease. A positive PET scan before HCT is associated with increased relapse risk but should not be interpreted as a barrier to a successful allograft. PET status does not appear to predict survival after allogeneic HCT for NHL.

Pretransplantation fluorine-18-deoxyglucose--positron emission tomography scan lacks prognostic value in chemosensitive B cell non-hodgkin lymphoma patients undergoing nonmyeloablative allogeneic stem cell transplantation

Whether chemosensitivity, as determined by positron emission tomography using fluorine-18-deoxyglucose (FDG-PET), is a requirement for successful allogeneic hematopoietic stem cell transplantation (allo-SCT) has yet to be established. We analyzed 88 patients with B cell non-Hodgkin lymphoma (B-NHL) for event-free (EFS) and overall survival (OS) according to computed tomography (CT) and FDG-PET criteria before uniform nonmyeloablative (NMA) allo-SCT. Patients who were chemosensitive, according to CT criteria, experienced significantly greater EFS (P < .001) and OS (P < .03) compared with those who were chemorefractory at the time of allo-SCT. Of 58 patients within this cohort who were chemosensitive by CT criteria, there was no difference in EFS (P = .85) or OS (P = .96) between FDG-PET-positive (Deauville 4 to 5, n = 24) and FDG-PET-negative (Deauville 1 to 3, n = 34) patients. There was no difference in survival according to age < or ≥ 60 years, prior autologous-stem cell transplantation, allograft characteristics, or histology. FDG-PET adds no prognostic value in chemosensitive B-NHL before NMA-allo-SCT.

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.

Metabolic regulation of cancer cell side population by glucose through activation of the Akt pathway

Side population (SP) cells within tumors are a small fraction of cancer cells with stem-like properties that can be identified by flow cytometry analysis based on their high ability to export certain compounds such as Hoechst 33342 and chemotherapeutic agents. The existence of stem-like SP cells in tumors is considered as a key factor contributing to drug resistance, and presents a major challenge in cancer treatment. Although it has been recognized for some time that tumor tissue niches may significantly affect cancer stem cells (CSCs), the role of key nutrients such as glucose in the microenvironment in affecting stem-like cancer cells and their metabolism largely remains elusive. Here we report that SP cells isolated from human cancer cells exhibit higher glycolytic activity compared to non-SP cells. Glucose in the culture environment exerts a profound effect on SP cells as evidenced by its ability to induce a significant increase in the percentage of SP cells in the overall cancer cell population, and glucose starvation causes a rapid depletion of SP cells. Mechanistically, glucose upregulates the SP fraction through ATP-mediated suppression of AMPK and activation of the Akt pathway, leading to elevated expression of the ATP-dependent efflux pump ABCG2. Importantly, inhibition of glycolysis by 3-BrOP significantly reduces SP cells in vitro and impairs their ability to form tumors in vivo. Our data suggest that glucose is an essential regulator of SP cells mediated by the Akt pathway, and targeting glycolysis may eliminate the drug-resistant SP cells with potentially significant benefits in cancer treatment.

State-of-the-Art Research on "Lymphomas: Role of Molecular Imaging for Staging, Prognostic Evaluation, and Treatment Response"

Lymphomas are heterogeneous but potentially curable group of neoplasms. Treatment of lymphomas has rapidly evolved overtime with significant improvement in the cure rate and reductions in treatment-related toxicities. Despite excellent results, treatment programs are continued to be developed to achieve better curative and safety profiles. In these patients individualized therapy schemes can be devised based on a well-defined risk categorization. The therapy efficacy can be increased early during therapy in non-responding patients with escalated therapy protocols or with the addition of radiation therapy, particularly, in advanced-stage or unfavorable risk patients. The increasing availability of positron emission tomography using 18F-fluorodeoxyglucose, particularly fused with computed tomography (FDG-PET/CT) has lead to the integration of this modality into the routine staging and restaging for lymphoma with convincing evidence that it is a more accurate imaging modality compared with conventional imaging techniques. FDG-PET/CT is also is a promising surrogate for tumor chemosensitivity early during therapy. This review will summarize published data on the utility of FDG-PET/CT imaging in the staging, restaging, and predicting therapy response in patients with lymphoma.

Allogeneic transplantation in the UK: an aggregation of marginal gains?

A number of advances in clinical practice that are considered routine in modern allogeneic transplant programmes lack definitive supporting evidence, partly because they may offer modest incremental benefits that are difficult to demonstrate in a statistically robust manner given the relatively small cohorts of patients who undergo such procedures. Nevertheless, these marginal gains probably contribute therapeutically meaningful overall benefit, particularly when aggregated. We review the evidence for a number of these practices in terms of impact on transplant outcomes, with particular reference to the setting of T cell depletion as widely practiced in the United Kingdom, including high resolution tissue typing, surveillance for and therapy of infectious complications, chimerism-directed immune modulation and more sensitive monitoring for residual or progressive disease.

PET scan integration in lymphoma management

SUMMARY Despite a marked improvement in lymphoma treatment outcome, current prognostic models, relying on a pretreatment set of static clinical variables, appear unable to support a risk-adapted therapeutic strategy. On the other hand, functional imaging with 18F-fluoro-2-deoxy-D-glucose (FDG)-PET proved to be a reliable tool to dynamically assess tumor FDG uptake changes during and after treatment. In this article we aim to review the prognostic value of FDG-PET in all the stages of Hodgkin’s and non-Hodgkin’s lymphoma management, without the intent to address the diagnostic value of PET or to replace available consensus guidelines. In particular we focused on two critical issues: the cost–effectiveness of PET in the overall strategy of lymphoma diagnosis and treatment; and ongoing clinical trials adopting an interim PET-based strategy to modulate treatment intensity based on PET results. Finally, new trends in multimodality imaging, as well as in new radiopharmaceutical tracers, are briefly reviewed.

Interim FDG-PET in Hodgkin lymphoma: a compass for a safe navigation in clinical trials?

Despite the rewarding results achieved in the treatment of Hodgkin lymphoma (HL), concerns have been raised regarding the long-term complications induced by therapy. Hence, the current challenge is to develop a new therapeutic strategy maintaining excellent patient outcome while reducing potentially life-threatening late adverse effects. Therefore, it would be beneficial to identify chemoresistant or refractory patients early during therapy for appropriate and timely escalation of treatment. Recently, compelling data have emerged on the prognostic role of interim [18F]-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) performed early during the course of treatment to predict ultimate outcome, even proving superior to conventional prognostic factors. Several ongoing prospective trials are exploring the feasibility of treatment de-escalation strategies in patients with a negative interim PET, as well as therapy escalation in advanced-stage HL patients who have a positive interim PET result. In this article, the published reports on the contribution of interim PET to the design of ongoing response-adapted clinical trials are reviewed. Moreover, some of the unresolved issues revolving around the suboptimal positive predictive value of interim PET are addressed with an emphasis on the interpretation criteria. A final remark on the appropriate use of interim PET is also provided.

18F-FDG-PET/CT in lymphoma: two decades of experience

The use of (18)F-FDG-PET/CT has changed the management of patients with lymphoma for the last two decades. This technique improves initial staging of the disease, making a prognostic approach and appropriate treatment planning, as well as monitoring therapy response of lymphoma. However, there are still controversial issues in medical literature that impact on daily clinical practice. This comprehensive literature review summarizes the current information regarding the potential use of (18)F-FDG-PET/CT in patients with lymphoma, highlighting the main applications and the current dilemmas for the nuclear medicine physicians at the time of the evaluation of these studies, trying to standardize criteria for its assessment, particularly in restaging and therapy monitoring.

A randomized study comparing yttrium-90 ibritumomab tiuxetan (Zevalin) and high-dose BEAM chemotherapy versus BEAM alone as the conditioning regimen before autologous stem cell transplantation in patients with aggressive lymphoma

BACKGROUND

High-dose chemotherapy combined with autologous stem-cell transplantation (ASCT) is the standard therapy for refractory/relapsed aggressive lymphoma. In the era of rituximab-containing frontline regimens, it is becoming more challenging to salvage patients in this setting, and novel approaches are required. This is a randomized study evaluating the safety and efficacy of standard-dose ibritumomab tiuxetan (Zevalin) combined with high-dose BEAM chemotherapy (Z-BEAM) and ASCT in refractory/relapsed aggressive lymphoma.

METHODS

Forty-three patients with CD20(+) -aggressive lymphoma were randomized to a treatment arm (Z-BEAM, n = 22) or control arm (BEAM alone, n = 21). Ibritumomab tiuxetan was given at 0.4 mCi/kg on day -14 before ASCT.

RESULTS

Patient characteristics, engraftment kinetics, and toxicity profile were similar between the 2 groups. Two-year progression-free survival (PFS) for all patients was 48% (95% confidence interval, 32%-64%): 59% and 37% after Z-BEAM and BEAM alone, respectively (P = .2). Multivariate analysis identified advanced age (hazard ratio [HR], 8.3; P = .001), high-risk disease (relapse within 12 months of diagnosis and/or secondary International Prognostic Index >2; HR, 2.8; P = .04), positive positron emission tomography-computed tomography pretransplant (HR, 2.4; P = .07), and BEAM alone (HR, 2.8; P = .03) as poor prognostic factors. Intermediate-risk patients with 1 or 2 risk factors had better PFS with Z-BEAM compared with BEAM: 69% and 29%, respectively (P = .07). Two-year overall survival was 91% and 62% after Z-BEAM and BEAM, respectively (P = .05). Similar prognostic factors determined survival. The HR for BEAM alone in the multivariate analysis was 8.1 (P = .01).

CONCLUSIONS

Standard-dose ibritumomab tiuxetan combined with BEAM high-dose chemotherapy is safe and possibly more effective than BEAM alone as a conditioning regimen for ASCT in the era of rituximab-containing chemotherapy regimens.

Second-line salvage chemotherapy for transplant-eligible patients with Hodgkin's lymphoma resistant to platinum-containing first-line salvage chemotherapy

BACKGROUND

The management of patients with relapsed or refractory Hodgkin's lymphoma who achieve less than a partial response to first-line salvage chemotherapy is unclear. The objective of this study was to evaluate response and outcomes to second-line salvage and autologous stem cell transplantation in patients not achieving a complete or partial response to platinum-containing first-line salvage chemotherapy.

DESIGN AND METHODS

Consecutively referred transplant-eligible patients with relapsed/refractory Hodgkin's lymphoma after primary chemotherapy received gemcitabine, dexamethasone, and cisplatin as first salvage chemotherapy. Those achieving a complete or partial response, and those with a negative gallium scan and stable disease with bulk <5 cm proceeded to high-dose chemotherapy and autologous stem cell transplantation. Patients with progressive disease or stable disease with a positive gallium scan or bulk ≥ 5 cm were given second salvage chemotherapy with mini-BEAM (carmustine, etoposide, cytarabine, melphalan). Patients who responded (according to the same definition) proceeded to autologous stem cell transplantation.

RESULTS

One hundred and thirty-one patients with relapsed/refractory Hodgkin's lymphoma received first-line salvage gemcitabine, dexamethasone, and cisplatin; of these patients 99 had at least a partial response (overall response rate 76%). One hundred and twelve (85.5%) patients proceeded to autologous stem cell transplantation, while the remaining 19 (14.5%) patients received mini-BEAM. Among these 19 patients, six had at least a partial response (overall response rate 32%), and nine proceeded to autologous stem cell transplantation. The remaining ten patients received palliative care. Seven of the nine patients transplanted after mini-BEAM had a subsequent relapse. Patients receiving second salvage mini-BEAM had poor outcomes, with a 5-year progression-free survival rate of 11% and a 5-year overall survival rate of 20%.

CONCLUSIONS

Patients who require a second salvage regimen to achieve disease control prior to autologous stem cell transplantation have a relatively poor outcome and should be considered for alternative treatment strategies.

The challenges of integrating molecular imaging into the optimization of cancer therapy

We review novel, in vivo and tissue-based imaging technologies that monitor and optimize cancer therapeutics. Recent advances in cancer treatment centre around the development of targeted therapies and personalisation of treatment regimes to individual tumour characteristics. However, clinical outcomes have not improved as expected. Further development of the use of molecular imaging to predict or assess treatment response must address spatial heterogeneity of cancer within the body. A combination of different imaging modalities should be used to relate the effect of the drug to dosing regimen or effective drug concentration at the local site of action. Molecular imaging provides a functional and dynamic read-out of cancer therapeutics, from nanometre to whole body scale. At the whole body scale, an increase in the sensitivity and specificity of the imaging probe is required to localise (micro)metastatic foci and/or residual disease that are currently below the limit of detection. The use of image-guided endoscopic biopsy can produce tumour cells or tissues for nanoscopic analysis in a relatively patient-compliant manner, thereby linking clinical imaging to a more precise assessment of molecular mechanisms. This multimodality imaging approach (in combination with genetics/genomic information) could be used to bridge the gap between our knowledge of mechanisms underlying the processes of metastasis, tumour dormancy and routine clinical practice. Treatment regimes could therefore be individually tailored both at diagnosis and throughout treatment, through monitoring of drug pharmacodynamics providing an early read-out of response or resistance.

Hodgkin's lymphoma therapy: past, present, and future

IMPORTANCE OF THE FIELD

The treatment of Hodgkin's lymphoma (HL) with the use of radiotherapy and systemic chemotherapy has been one of the success stories of modern oncology. HL therapy has been the paradigm for the systematic evaluation of different curative modalities, resulting in cure for the majority of patients. The current focus is on designing initial therapeutic strategies that retain efficacy and minimize long-term toxicity. Appropriate use of pathologic, clinical, biologic and radiologic prognostic factors in identification of aggressive HL is paramount in designing a successful therapeutic strategy.

AREAS COVERED IN THIS REVIEW

This review addresses the current and future use of prognostic tools, including PET scanning and other biomarkers, in identifying patients with aggressive HL, with reference to publications from the last two decades. The current standard approaches with the use of combined modality therapy and systemic chemotherapy as well as the promising role of future response-adapted strategies is reviewed.

WHAT THE READER WILL GAIN

The reader will obtain a comprehensive review of risk assessment strategies as well as current and investigational therapeutic approaches in the management of HL.

TAKE HOME MESSAGE

In HL, appropriate utilization of risk assessment strategies is required to maximize therapeutic outcomes while minimizing toxicity, especially long-term toxicity. Response-adapted therapy utilizing PET has the potential to profoundly improve the therapeutic landscape in HL.

Prognostication and Risk-Adapted Therapy of Hodgkin's Lymphoma Using Positron Emission Tomography

The use of ¹⁸F-fluorodeoxyglucose positron emission tomography (FDG-PET) for response assessment in lymphoma is now widespread. Prognostic information obtained from PET performed after two to three cycles of chemotherapy may guide more individualized, risk-adapted therapeutic strategies. Progress in the risk stratification of Hodgkin's lymphoma through midtreatment PET is reviewed, with a focus on management implications in newly diagnosed and relapsed disease. How to tailor treatment on the basis of the interim PET result is not yet defined but is the subject of ongoing trials.

Patency and clinical outcomes of transjugular intrahepatic portosystemic shunt with polytetrafluoroethylene-covered stents versus bare stents: a meta-analysis

BACKGROUND AND AIM

 Transjugular intrahepatic portosystemic shunt (TIPS) with polytetrafluoroethylene-(PTFE)-covered stent has been increasingly used for patients with complications of portal hypertension. It is still debated whether the new endoprostheses will improve some clinical outcomes (except for shunt patency) compared to the bare stents. The aims of our meta-analysis were to explore the patency and clinical outcomes of TIPS with PTFE-covered stent-grafts versus bare stents.

METHODS

Pertinent studies were retrieved through PubMed (1950-2010), MEDLINE (1950-2010), and reference lists of key articles. Outcome measures were primary patency, risk of encephalopathy and survival. Time-to-event data analysis was used to calculate the overall hazard ratios (HR).

RESULTS

Six studies were identified including a total of 1275 patients (346 TIPS with PTFE-covered stent-grafts and 929 TIPS with bare stents). Pooled shunt patency data from four eligible studies suggested a significant improvement of primary patency in patients who were treated with PTFE-covered stent-grafts (HR = 0.28, 95% confidence interval [CI] 0.20-0.35). Pooled encephalopathy data from three eligible studies suggested a significant reduction of risk in the PTFE-covered group (HR = 0.65, 95%CI 0.45-0.86). Pooled survival data from four eligible studies also suggested a significant decrease of mortality in the PTFE-covered group (HR = 0.76, 95%CI 0.58-0.94). No statistical heterogeneity was observed between studies for either outcome.

CONCLUSIONS

This meta-analysis shows that the use of PTFE-covered stent-grafts clearly improves shunt patency without increasing the risk of hepatic encephalopathy and with a trend towards better survival.

Fluorine-18-fluorodeoxyglucose positron emission tomography in response assessment before high-dose chemotherapy for lymphoma: a systematic review and meta-analysis

BACKGROUND

We conducted a systematic review and meta-analysis to better define the prognostic ability of fluorine-18-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) following salvage chemotherapy for relapsed or refractory Hodgkin's lymphoma (HL) and aggressive non-Hodgkin's lymphoma.

METHODS

We searched PubMed (from inception to January 31, 2010), bibliographies, and review articles without language restriction. Two assessors independently assessed study characteristics, quality, and results. We performed a meta-analysis to determine prognostic accuracy.

RESULTS

Twelve studies including 630 patients were eligible. The most commonly evaluated histologies were diffuse large B-cell lymphoma (n = 313) and HL (n = 187), which were typically treated with various salvage and high-dose chemotherapy regimens. Studies typically employed nonstandardized protocols and diagnostic criteria. The prognostic accuracy was heterogeneous across the included studies. (18)F-FDG PET had a summary sensitivity of 0.69 (95% confidence interval [CI], 0.56-0.81) and specificity of 0.81 (95% CI, 0.73-0.87). The summary estimates were stable in sensitivity analyses. In four studies that performed direct comparisons between PET and conventional restaging modalities, PET had a superior accuracy for predicting treatment outcomes. Subgroup and metaregression analyses did not identify any particular factor to explain the observed heterogeneity.

CONCLUSION

(18)F-FDG PET performed after salvage therapy appears to be an appropriate test to predict treatment failure in patients with refractory or relapsed lymphoma who receive high-dose chemotherapy. Some evidence suggests PET is superior to conventional restaging for this purpose. Given the methodological limitations in the primary studies, prospective studies with standardized methodologies are needed to confirm and refine these promising results.

[Gynecologic examinations]

Tumours contain a small number of treatment-resistant cancer stem cells (CSCs), and it is through these that tumour regrowth originates at secondary sites, thus rendering CSCs an attractive target for treatment. Cancer cells adapt cellular metabolism for aggressive proliferation. Tumour cells use less efficient glycolysis for the production of ATP and increasing tumour mass, instead of oxidative phosphorylation (OXPHOS). CSCs show distinct metabolic shift and, depending on the cancer type, can be highly glycolytic or OXPHOS dependent. Since Wnt signalling promotes glycolysis and tumour growth, we investigated the effect of the Wnt antagonist secreted frizzled-related protein 4 (sFRP4) on CSC metabolism. We demonstrate that sFRP4 has a prominent role in basal glucose uptake in CSCs derived from breast and prostate tumour cell lines. We show that sFRP4 treatment on CSCs isolated with variable glucose content induces metabolic reprogramming by relocating metabolic flux to glycolysis or OXPHOS. Altogether, sFRP4 treatment compromises cell proliferation and critically affects cell survival mechanisms such as viability, glucose transporters, pyruvate conversion, mammalian target of rapamycin, and induces CSC apoptosis under conditions of variable glucose content. Our findings provide the feasibility of using sFRP4 to inhibit CSC survival in order to induce metabolic reprogramming in vivo.