Search Results (28)

Background: The accurate prediction of pathological complete response (pCR) following total neoadjuvant therapy (TNT) is crucial for optimising treatment protocols in locally advanced rectal cancer (LARC). Although conventional imaging techniques such as MRI show limitations in assessing treatment response, metabolic imaging utilising 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET-CT) provides distinctive information by quantifying tumour glycolytic activity. This study investigates the predictive value of sequential 18F-FDG PET-CT parameters, focusing on Total Lesion Glycolysis (TLG), in predicting pCR after TNT. Methods: We conducted a retrospective analysis of 33 LARC patients (T3–4/N0–1) treated with TNT (neoadjuvant-chemoradiation followed by consolidation FOLFOX chemotherapy). Sequential PET-CT scans were performed at baseline, interim (after 4 cycles of FOLFOX), and post-TNT. Metabolic parameters, including maximum standardised uptake value (SUVmax) and TLG, were measured. Receiver operating characteristic (ROC) analysis assessed the predictive performance of these parameters for pCR. Results: The pCR rate was 21.2% (7/33). Post-TNT TLG ≤ 10 demonstrated excellent predictive accuracy for pCR (AUC 0.887, 92.3% sensitivity, 85.7% specificity, and 96.0% PPV), outperforming SUVmax (AUC 0.843). Interim TLG ≤ 10 also showed a strong predictive value (AUC 0.824, 100% sensitivity, and 71.4% specificity). Conclusions: TLG may serve as a reliable metabolic biomarker for predicting pathologic complete response (pCR) after total neoadjuvant therapy (TNT) in locally advanced rectal cancer (LARC). Its inclusion in clinical decision-making could improve patient selection for organ preservation strategies, thereby reducing the need for unnecessary surgeries in the future. However, given that the study is based on a small retrospective design, the findings should be interpreted with caution and used alongside other decision-making tools until more comprehensive data are collected from larger studies. Full article

Background/Objectives: Circulating tumor DNA (ctDNA) has emerged as a promising biomarker for non-invasive tumor monitoring in diffuse large B-cell lymphoma (DLBCL). Methods: In this study, 52 patients with newly diagnosed advanced-stage DLBCL treated with R-CHOP underwent serial ctDNA analysis at baseline, interim (after three cycles), and end of treatment. The prognostic significance of ctDNA dynamics was evaluated, and its predictive value was compared with the PET/CT response. Results: Targeted next-generation sequencing revealed baseline ctDNA in 98.1% of patients, with 74.7% concordance to tumor tissue genotyping. Higher baseline ctDNA levels correlated with elevated LDH, older age, and high IPI scores. A ≥2-log reduction in ctDNA at interim was significantly associated with improved overall survival (p = 0.004), though not with progression-free survival. Notably, combining interim ctDNA dynamics with PET/CT results enhanced the predictive accuracy for treatment outcomes, particularly among patients with partial metabolic responses. Conclusions: These findings support the clinical utility of ctDNA for dynamic risk assessment in DLBCL, and suggest that integrating ctDNA with imaging biomarkers may guide more personalized therapeutic strategies. Further validation using highly sensitive ctDNA assays is warranted to optimize its role in routine clinical practice. Full article

Primary mediastinal large B-cell lymphoma (PMLBCL) is a rare and aggressive non-Hodgkin lymphoma (NHL), considered a specific entity with proper characteristics, therapies, and prognosis. First-line treatment is not unique, and subsequent strategies in case of disease persistence or relapse are the subject of debate and studies. In this scenario, [18F]FDG PET/CT plays a pivotal role both in characterizing the mediastinal mass, the main feature of PMLBCL, in staging, in restaging during therapy (interim PET), and at the end of treatment (EoT PET), to guide clinical management and give prognostic insights. The main issue with PMLBCL is distinguishing viable disease from residual fibrotic/inflammatory mass after therapy and, consequently, settling the next clinical strategy. Novel therapeutic approaches are ongoing and associated with the deepening of [18F]FDG PET/CT potentials as a principal tool in this context. In this review, we will explore PMLBCL from a Nuclear Medicine point of view to help clinicians in the management of these patients. Full article

Background/Objectives: This study aimed to determine whether interim PET/CT (iPET) scans could identify follicular lymphoma (FL) patients at high risk of relapse following first-line therapy. Methods: A total of 117 FL patients who underwent iPET scans were included, with responses interpreted using the Deauville score (DS). Progression-free survival (PFS) was evaluated over a median follow-up of 34 months. Results: Overall, 34% of patients were classified as iPET (+), with significantly worse estimated 5-year PFS compared to iPET (−) patients (34% vs. 76%, hazard ratio 4.3, p < 0.001). Multivariate analysis confirmed iPET (+) as an independent predictor of PFS. Conclusions: Interim PET results are significant predictors of PFS in FL first-line therapy and could inform response-adapted treatment strategies. Full article

Background/Objectives This study aimed to evaluate whether very early interim ¹⁸F-fluoro-2-deoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) after a single cycle of first-line chemotherapy predicts long-term survival outcome in patients with diffuse large B-cell lymphoma (DLBCL). Methods A total of 51 patients (31 males and 20 females; mean age 55 years) had four FDG PET/CT studies, at baseline and after one, three, and six cycles of chemotherapy (PET0, PET1, PET3, and PET6). Visually and quantitatively assessed PET parameters were analyzed for associations with long-term survival. Results The estimated 10-year progression-free survival (PFS) and overall survival (OS) was 48% and 61%, respectively. During a median follow-up of 63 months (range 9–134), 17 patients (33%) exhibited disease progression and 15 (29%) died. On PET1, all but one showed decreased FDG uptake, and all showed decreased metabolic tumor volume. None of the PET1 or PET3 parameters were associated with survival. The PET6 parameters retained independent predictive value for OS after adjustment for the International Prognostic Index. Negative PET6 was associated with longer PFS (mean 99 vs. 50 mo, p = 0.04) and OS (mean 107 vs. 57 mo, p = 0.02). Con-clusions The FDG PET/CT parameters obtained after a single cycle of chemotherapy were not associated with long-term survival in DLBCL, while negative end-of-therapy FDG PET/CT was associated with longer PFS and OS. Tumor regression very early into first-line chemotherapy was not as clinically relevant as the presence of viable tumor on FDG PET/CT at the end of therapy for predicting long-term outcomes. Full article

Introduction: Follicular lymphoma (FL) is a heterogeneous disease, and identifying high-risk patients early is crucial for optimal management. This study aimed to evaluate the prognostic significance of interim positron emission tomography/computed tomography (PET/CT) in newly diagnosed FL patients undergoing first-line treatment. Methods: This single-center, retrospective study included 103 patients with newly diagnosed FL who underwent interim PET/CT. The primary endpoint was progression-free survival (PFS). The prognostic value of positive interim PET/CT, Deauville scores, and maximum standardized uptake values (SUVmax) were analyzed among other clinical features. Results: A total of 30 patients (29.1%) were deemed interim PET/CT-positive. The interim PET/CT-positive group demonstrated a significantly shorter median PFS compared to the interim PET/CT-negative group (17 months vs. not reached, respectively; p < 0.0001). Similarly, patients with Deauville scores of 1–3 had better PFS, with median survival not yet reached, while those with higher Deauville scores exhibited poorer progression-free survival and a median survival of 18 months. Notably, patients with an interim PET/CT SUVmax exceeding 3.365 experienced significantly shorter median survival compared to those with lower values. Discussion: Our findings support the use of interim PET/CT as a prognostic tool in FL. These results are consistent with other studies, although some debate exists regarding the optimal PET/CT metric. Further research is needed to validate these findings and explore personalized treatment strategies based on interim PET/CT results. Full article

Background: Bleomycin is an oncolytic and antibiotic agent used to treat various human cancers because of its antitumor activity. Unfortunately, up to 46% of the patients treated with bleomycin develop drug-induced interstitial lung disease (DIILD) and potentially life-threatening interstitial pulmonary fibrosis. Tools and biomarkers for predicting and detecting DIILD are limited. Therefore, we aimed to evaluate the feasibility of ¹⁸F-FDG PET/CT, PET radiomics, and machine learning in distinguishing DIILD in an explorative pilot study. Methods: Eighteen Hodgkin’s lymphoma (HL) patients, of whom 10 developed DIILD after treatment with bleomycin, were retrospectively included. Five diffuse large B-cell lymphoma (DLBCL) patients were included as a control group since they were not treated with bleomycin. All patients underwent ¹⁸F-FDG PET/CT scans before (baseline) and during treatment (interim). Structural changes were assessed by changes in Hounsfield Units (HUs). The ¹⁸F-FDG PET scans were used to assess metabolic changes by examining the feasibility of 504 radiomics features, including the mean activity of the lungs (SUVmean). A Random Forest (RF) classifier evaluated the identification and prediction of DIILD based on PET radiomics features. Results: HL patients who developed DIILD showed a significant increase in standard SUV metrics (SUVmean; p = 0.012, median increase 37.4%), and in some regional PET radiomics features (texture strength; p = 0.009, median increase 101.6% and zone distance entropy; p = 0.019, median increase 18.5%), while this was not found in HL patients who did not develop DIILD and DLBCL patients. The RF classifier correctly identified DIILD in 72.2% of the patients and predicted the development of DIILD correctly in 50% of the patients. There were no significant differences in HUs over time within all three patient groups. Conclusions: Our explorative longitudinal pilot study suggests that certain regional ¹⁸F-FDG PET radiomics features can effectively identify DIILD in HL patients treated with bleomycin, as significant longitudinal increases were observed in SUVmean, texture strength, and zone distance entropy after the development of DIILD. The metabolic activity of these features did not significantly increase over time in DLBCL patients and HL patients who did not develop DIILD. This indicates that ¹⁸F-FDG PET radiomics, with and without machine learning, might serve as potential biomarkers for detecting DIILD. Full article

Purpose: We aimed to develop a nomogram able to predict treatment failure, skeletal events, and overall survival (OS) in patients with castration-resistant prostate cancer with bone metastases (CRPC-BM) treated with Radium-223 dichloride (²²³Ra). Patients and Methods: Patients from the Castilla-La Mancha Spanish region were prospectively included in the ChoPET-Rad multicenter study from January 2015 to December 2022. Patients underwent baseline, interim, and end-of-treatment bone scintigraphy (BS) and ¹⁸F-Fluorocholine PET/CT (FCH PET/CT) scans, obtaining multiple imaging radiomics as well as clinical and biochemical variables during follow-up and studying their association with the previously defined end-points. Survival analysis was performed using the Kaplan–Meier method and Cox regression. Multivariate logistic and Cox regression models were calculated, and these models were depicted by means of nomograms. Results: Median progression-free survival (PFS) and OS were 4 and 14 months (mo), respectively. The variables that showed independent and significant association with therapeutic failure were baseline alkaline phosphatase (AP) levels (p = 0.022) and the characteristics of BM on the CT portion of PET/CT (p = 0.017). In the case of OS, the significant variables were therapeutic failure (p = 0.038), the number of lines received after ²²³Ra (p < 0.001), average SUVmax (p = 0.002), bone marrow infiltration in FCH PET/CT (p = 0.006), and interim FCH PET/CT response (p = 0.048). Final nomograms included these variables, showing good discrimination among the 100 patients included in our study. In the study of skeletal events, only OS showed a significant association in the multivariate analysis, resulting in an inconsistent nomogram design. Conclusions: FCH PET/CT appears to be a good tool for evaluating patients eligible for treatment with ²²³Ra, as well as for their follow-up. Thus, findings derived from it, such as the morphological characteristics of BM in the CT, bone marrow infiltration, or the response to ²²³Ra in the interim study, have proven to be solid and useful variables in the creation of nomograms for predicting therapeutic failure and OS. Full article

The last 3 decades have witnessed a major evolution in the treatment of advanced-stage Hodgkin lymphoma (HL). The most prominent of these developments include the introduction of the international prognostic scoring (IPS) system; therapeutic decision-making based on both IPS and interim PET/CT data; the finding that a negative interim PET/CT result could be safely used for treatment de-escalation; the introduction of intensive combination chemotherapy like escalated BEACOPP (bleomycin, etoposide, adriamycin, cyclophosphamide, oncovin (vincristine), procarbazine, and prednisone); and further modification of this protocol with the incorporation of a conjugated anti-CD30 antibody brentuximab vedotin (BV) into first-line regimens, like BV-AVD (BV+ adriamycin, vinblastine and dacarbazine) and BrECADD (brentuximab vedotin, etoposide, cyclophosphamide, doxorubicin, dacarbazine, and dexamethasone). The accruing data about the toxicity of the escalated BEACOPP protocol have led to decreasing the number of therapeutic cycles, substitution of toxic agents like procarbazine with dacarbazine (e.g., BEACOPDac), and reduction/omission of radiation therapy. Lately, a significant advancement has been made by the integration of checkpoint inhibitors in the first-line treatment, with preliminary results demonstrating the superiority of anti-PD1 combined with chemotherapy (nivolumab-AVD) compared to the BV-AVD regimen. This review aims to analyze recently published studies whose findings could change the treatment practice in advanced-stage HL. Full article

Fluorine-18 fluorodeoxyglucose ([¹⁸F]FDG) is nowadays the leading positron emission tomography (PET) tracer for routine clinical work-ups in hematological malignancies; however, it is limited by false positive findings. Notably, false positives can occur in inflammatory and infective cases or in necrotic tumors that are infiltrated by macrophages and other inflammatory cells. In this context, 3′-deoxy-3′-[¹⁸F]fluorothymidine ([¹⁸F]FLT) has been shown to be a promising imaging biomarker of hematological malignant cell proliferation. In this review, a total of 15 papers were reviewed to collect literature data regarding the clinical application of [¹⁸F]FLT PET/CT in hematological malignancies. This imaging modality seems to be a suitable tool for noninvasive assessment of tumor grading, also showing a correlation with Ki-67 immunostaining. Moreover, [¹⁸F]FLT PET/CT demonstrated high sensitivity in detecting aggressive lymphoma lesions, especially when applying a standardized uptake value (SUV) cutoff of 3. At baseline, the potential of [¹⁸F]FLT imaging as a predictive tool is demonstrated by the low tracer uptake in patients with a complete response. However, its use is limited in evaluating bone diseases due to its high physiological uptake in bone marrow. Interim [¹⁸F]FLT PET/CT (iFLT) has the potential to identify high-risk patients with greater precision than [¹⁸F]FDG PET/CT, optimizing risk-adapted therapy strategies. Moreover, [¹⁸F]FLT uptake showed a greater ability to differentiate tumor from inflammation compared to [¹⁸F]FDG, allowing the reduction of false-positive findings and making the first one a more selective tracer. Finally, FLT emerges as a superior independent predictor of PFS and OS compared to FDG and ensures a reliable early response assessment with greater accuracy and predictive value. Full article

This study evaluated the prognostic significance of FDG PET/CT in patients with nodal peripheral T-cell lymphoma (PTCL). We retrospectively reviewed patients with histologically confirmed nodal PTCL who underwent FDG PET/CT at baseline, after three cycles of first-line chemotherapy (interim), and at the end of therapy. Response was assessed visually using the Deauville 5-point scale (D5PS); scores of 1, 2, and 3 were considered PET-negative, and scores of 4 and 5 were considered PET-positive. The associations between FDG PET/CT findings and survival were assessed using Cox regression analysis. A total of 79 patients (44 males and 35 females; median age 56 years) were included in this study. In response assessment, 17 (22%) had an interim PET-positive result and 10 (13%) had an end-of-therapy PET-positive result. During a median follow-up of 50 months, 37 patients (47%) presented with disease progression and 30 patients (38%) died. The estimated 5-year progression-free survival (PFS) and overall survival (OS) were 57% and 64%, respectively. An interim PET-positive result was the only significant indicator of PFS. Higher International Prognostic Index and end-of-therapy PET-positive result were significant independent prognostic factors of OS. Interim and end-of-therapy FDG PET/CT responses based on D5PS are meaningful in predicting the outcomes of patients with nodal PTCL. Full article

This study aims to assess the change in uptake to reference organs, including the liver, parotid and salivary glands after radioligand therapy (RLT) with [¹⁷⁷Lu]Lu-PSMA-617 in relation to pretreatment imaging metrics. Eighty-five patients with mCRPC underwent [⁶⁸Ga]Ga-PSMA-11 PET/CT imaging prior to (pre RLT PET) and after (post RLT PET) a median of 3 (IQR 2-6) RLT cycles with [¹⁷⁷Lu]Lu-PSMA-617. PSMA-positive tumor burden was stratified into 4 groups based on modified PROMISE criteria (oligofocal, multifocal, disseminated, diffuse). Uptake (SUV_mean, SUV_max) in liver tissue, parotid and submandibular glands was measured. A control group was established with 54 patients who had received two separate PET acquisitions following the same protocol (PET1, PET2) within 12 months for localized or oligofocal prostate cancer without RLT in the interim. Baseline uptake values (SUV_mean, SUV_max) in parotid (10.8 ± 3.2, 16.8 ± 5.4) and submandibular glands (11.3 ± 2.8, 18.1 ± 4.7) are 2-fold compared to liver uptake (4.9 ± 1.4, 7.7 ± 2.0), with no significant change between PET 1 and PET 2 in the control group. In the RLT group, increasing tumor burden class is significantly associated with decreasing uptake in the liver (p = 0.013), parotid (p < 0.001) and submandibular glands (p < 0.001); this tumor sink effect by respective tumor burden is widely maintained after RLT (p = 0.011, p < 0.001, p < 0.001). RLT has a significant impact on salivary gland uptake with decreasing values per patient in all groups of disease burden change (up to −30.4% in submandibular glands, p < 0.001), while liver tissue shows rising values in patients with declining tumor burden throughout RLT (+18.6%, p = 0.020). Uptake in liver tissue and salivary glands on [⁶⁸Ga]Ga-PSMA-11 PET/CT imaging is inversely related to tumor burden prior to and following RLT with [¹⁷⁷Lu]Lu-PSMA-617. Per patient, salivary gland uptake is further reduced throughout RLT independently from tumor burden, while changes in liver uptake remain burden-dependent. Liver and salivary gland uptake-derived metrics and segmentation thresholds may thus be of limited value when used as reference for response assessment to RLT. Full article

Bleomycin-induced pulmonary toxicity (BPT) is a serious and potentially fatal complication of bleomycin, a key component of Hodgkin lymphoma (HL) treatment. Before ours, only one published study evaluated the predictability of 18F-FDG-PET/CT for the early diagnosis of BPT. In this retrospective cohort study, 18F-FDG-PET/CT scans of adult HL patients treated with bleomycin at an urban academic center over five years were assessed by radiologists blinded to the clinical information, and scans were correlated with clinical BPT. We found 11 HL patients with 54 interim or end-of-treatment 18F-FDG-PET/CT scans who had received bleomycin. Five of the eleven (5/11, 45%) patients had radiographic changes in PET/CT and developed clinical BPT. Patients with clinical BPT had higher FDG uptake in lungs compared to those who did not (SUV_max mean 2.66 (CI 1.8–3.7) vs. 0.86 (CI 0.4–1.9), Mann–Whitney U test, p < 0.05). In a separate cohort analysis, we compared HL patients with clinical BPT (9/25, 36%) and without clinical BPT (16/25, 64%) to assess potential risk factors. Low hemoglobin (p = 0.037) and high ESR values (p = 0.0289) were associated with clinical BPT. Furthermore, gender, stage, histology, prior lung radiation, G-CSF, or steroids did not significantly confer a higher risk of BPT. 18F-FDG-PET/CT imaging, which is routinely used to assess treatment response in HL, is useful for early detection of BPT, which can have high mortality and morbidity. Full article

Recently, several studies introduced the potential prognostic usefulness of maximum tumor dissemination (Dmax) measured by 2-deoxy-2-fluorine-18-fluoro-D-glucose positron-emission tomography/computed tomography (¹⁸F-FDG PET/CT). Dmax is a simple three-dimensional feature that represents the maximal distance between the two farthest hypermetabolic PET lesions. A comprehensive computer literature search of PubMed/MEDLINE, Embase, and Cochrane libraries was conducted, including articles indexed up to 28 February 2023. Ultimately, 19 studies analyzing the value of ¹⁸F-FDG PET/CT Dmax in patients with lymphomas were included. Despite their heterogeneity, most studies showed a significant prognostic role of Dmax in predicting progression-free survival (PFS) and overall survival (OS). Some articles showed that the combination of Dmax with other metabolic features, such as MTV and interim PET response, proved to better stratify the risk of relapse or death. However, some methodological open questions need to be clarified before introducing Dmax into clinical practice. Full article

This study investigated the predictive role of baseline ¹⁸F-FDG PET/CT (bPET/CT) radiomics from two distinct target lesions in patients with classical Hodgkin’s lymphoma (cHL). cHL patients examined with bPET/CT and interim PET/CT between 2010 and 2019 were retrospectively included. Two bPET/CT target lesions were selected for radiomic feature extraction: Lesion_A, with the largest axial diameter, and Lesion_B, with the highest SUV_max. Deauville score at interim PET/CT (DS) and 24-month progression-free-survival (PFS) were recorded. Mann–Whitney test identified the most promising image features (p < 0.05) from both lesions with regards to DS and PFS; all possible radiomic bivariate models were then built through a logistic regression analysis and trained/tested with a cross-fold validation test. The best bivariate models were selected based on their mean area under curve (mAUC). A total of 227 cHL patients were included. The best models for DS prediction had 0.78 ± 0.05 maximum mAUC, with a predominant contribution of Lesion_A features to the combinations. The best models for 24-month PFS prediction reached 0.74 ± 0.12 mAUC and mainly depended on Lesion_B features. bFDG-PET/CT radiomic features from the largest and hottest lesions in patients with cHL may provide relevant information in terms of early response-to-treatment and prognosis, thus representing an earlier and stronger decision-making support for therapeutic strategies. External validations of the proposed model are planned. Full article