Tumor Pseudoprogression

RATIONALE AND OBJECTIVES: Gliomas are aggressive brain tumors with a poor prognosis. Assessing treatment response is challenging because magnetic resonance imaging (MRI) may not distinguish true progression (TP) from pseudoprogression (PsP). This review aims to discuss imaging techniques and liquid biopsies used to distinguish TP from PsP. MATERIALS AND METHODS: This review synthesizes existing literature to examine advances in imaging techniques, such as magnetic resonance diffusion imaging (MRDI), perfusion-weighted imaging (PWI) MRI, and liquid biopsies, for identifying TP or PsP through tumor markers and tissue characteristics...

We report two patients who displayed evidence of localized ocular inflammation after CAR T-cell infusion. To manage the resulting severe visual impairment, systemic corticosteroids were administered to both patients. This treatment led to a reduction in local inflammation and restored vision in one of the patients.

Tumor-treating fields (TTFields) is an established treatment modality for glioblastoma. False progression to chemoradiation is a known problem in patients with glioblastoma multiforme (GBM), with most cases occurring within three months of radiation therapy. In this report, we present two cases of delayed pseudoprogression caused by TTFields. Two patients with GBM who received TTFields showed signs of radiographic progression six months after the completion of radiation therapy. Patient 1 was a 37-year-old female with a glioblastoma in the right temporal lobe...

BACKGROUND: Programmed cell death protein-1/programmed cell death protein-ligand 1 (PD-1/PD-L1) inhibitor and chemotherapy are the standard treatment for advanced non-small cell lung cancer (NSCLC) without sensitizing mutations. However, patients with untreated, symptomatic or recently-irradiated brain metastases (BMs) are mostly excluded from immunochemotherapy trials. This study aims to evaluate the intracranial response pattern, tolerability and biomarkers of tislelizumab plus chemotherapy in NSCLC with untreated, symptomatic or recently-irradiated BM...

The activity of immune checkpoint inhibitors (ICIs) in patients with metastatic melanoma is often monitored using fluorine-18-fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) scans. However, distinguishing disease progression (PD) from pseudoprogression (PsPD), where increased FDG uptake might reflect immune cell activity rather than tumor growth, remains a challenge. This prospective study compared the efficacy of dual-time point (DTP) FDG-PET/CT with modified response criteria (PERCIMT) in differentiating PsPD from PD...

Following the previous part of the narrative review on artificial intelligence (AI) applications in positron emission tomography (PET) using tracers rather than 18 F-fluorodeoxyglucose ([18 F]F-FDG), in this part we review the impact of PET-derived radiomics data on the diagnostic performance of other PET radiotracers, 18 F-O-(2-fluoroethyl)-L-tyrosine ([18 F]F-FET), 18 F-Fluorothymidine ([18 F]F-FLT) and 11 C-Methionine ([11 C]C-MET). [18 F]F-FET-PET, using an artificial amino acid taken up into upregulated tumoral cells, showed potential in lesion detection and tumor characterization, especially with its ability to reflect glioma heterogeneity...

The lack of early detection and a high rate of recurrence/progression after surgery are defined as the most common causes of a very poor prognosis of Gliomas. The developments of quantification systems with special regards to artificial intelligence (AI) on medical images (CT, MRI, PET) are under evaluation in the clinical and research context in view of several applications providing different information related to the reconstruction of imaging, the segmentation of tissues acquired, the selection of features, and the proper data analyses...

BACKGROUND: One of the most frequent phenomena in the follow-up of glioblastoma is pseudoprogression, present in up to half of the cases. The clinical usefulness to discriminate this phenomenon through magnetic resonance imaging and nuclear medicine is not yet standardized, in this study we used machine learning on multiparametric magnetic resonance imaging to explore discriminators of this phenomenon. METHODS: For the study, 30 patients diagnosed with IDH wild-type glioblastoma operated on at both study centers in the period 2011-2020 were selected, 15 patients correspond to early tumor progression and 15 patients to pseudo-progression, using unsupervised learning, the number of clusters and tumor segmentation has been carried out using gap-stat and k-means method, adjusting to voxel adjacency...

BACKGROUND: Adverse clinical events cause significant morbidity in patients with glioblastoma (GBM). We examined whether genomic alterations were associated with adverse events (AEs) in GBM patients. METHODS: We identified adults with histologically confirmed IDH-wildtype GBM with targeted next-generation sequencing (OncoPanel) at Dana Farber Cancer Institute from 2013-2019. Seizure at presentation, lymphopenia, thromboembolic events, pseudoprogression, and early progression (within 6 months of diagnosis) were identified as AEs...

BACKGROUND: Differentiating post-radiation MRI changes from progressive disease (PD) in glioblastoma (GBM) patients represents a major challenge. The clinical problem is two-sided; avoid termination of effective therapy in case of pseudoprogression (PsP) and continuation of ineffective therapy in case of PD. We retrospectively assessed the incidence, management, and prognostic impact of PsP and analyzed factors associated with PsP in a GBM patient cohort. METHODS: Consecutive GBM patients diagnosed in the South-Eastern Norway Health Region from 2015 to 2018 who had received RT and follow-up MRI were included...

PURPOSE: In this study we gathered and analyzed the available evidence regarding 17 different imaging modalities and performed network meta-analysis to find the most effective modality for the differentiation between brain tumor recurrence and post-treatment radiation effects. METHODS: We conducted a comprehensive systematic search on PubMed and Embase. The quality of eligible studies was assessed using the Assessment of Multiple Systematic Reviews-2 (AMSTAR-2) instrument...

The microsatellite instability (MSI) phenotype is related to a deficiency of the DNA mismatch repair (dMMR) system and is observed in 5% of metastatic colorectal cancers (mCRCs). MSI/dMMR phenotype testing should be routine for all CRCs regardless of stage. Two complementary techniques with a high concordance (90-97%) allow us to determine the MSI/dMMR status of a tumor: immunohistochemistry and polymerase chain reaction. Since 2020 and the results of the phase III KEYNOTE 177 trial, pembrolizumab [anti-programmed cell death protein 1 (PD1)] is the new standard of care in first-line MSI/dMMR mCRC...

The follow-up of glioma patients after therapeutic intervention remains a challenging topic, as therapy-related changes can emulate true progression in contrast-enhanced magnetic resonance imaging. 18 F-fluoroethyl-tyrosine (18 F-FET) is a radiopharmaceutical that accumulates in glioma cells due to an increased expression of L-amino acid transporters and, contrary to gadolinium, does not depend on blood-brain barrier disruption to reach tumoral cells. It has demonstrated a high diagnostic value in the differentiation of tumoral viability and pseudoprogression or any other therapy-related changes, especially when combining traditional visual analysis with modern radiomics...

A consensus guideline, iRECIST, was developed by the Response Evaluation Criteria in Solid Tumours (RECIST) working group for the use of the modified RECIST version 1.1 in cancer immunotherapy trials. iRECIST was designed to separate pseudoprogression from real progression. However, this is not the only ambiguous situation. In clinical immunotherapy trials, stable disease may reflect three tumor responses, including real stable disease, progressive disease and responsive disease. The prediction of a " true complete/partial response" is also important...

Immunotherapeutic agents and in particular immune checkpoint inhibitors (ICI) have opened up extensive new therapeutic possibilities in oncology over the last decade. For numerous entities these substances have improved the clinical outcome, sometimes as monotherapy but also in combination with cytostatic or targeted treatment. In routine clinical practice the type of radiological response often differs from what is seen under cytostatic treatment: a mixed response of individual lesions is more frequently observed and occasionally also a response after an initial progress (so-called pseudoprogression)...

Esophageal squamous cell carcinoma (ESCC) is an aggressive malignant tumor with a poor prognosis due to insidious symptoms that make early diagnosis difficult. Despite the combination of multiple treatment modalities, the recurrence and mortality rates of ESCC remain high. Neoadjuvant chemotherapy combined with immunotherapy is an emerging treatment modality that improves the prognosis of patients with ESCC. However, owing to the presence of hyperprogression and pseudoprogression, the currently used methods cannot accurately evaluate the efficacy of this therapy in patients, thus creating an evaluation bias and depriving these patients of the opportunity to benefit...

PURPOSE: Perfusion-weighted (PWI) magnetic resonance imaging (MRI) and O‑(2-[18F]fluoroethyl-)-l-tyrosine ([18F]FET) positron emission tomography (PET) are both useful for discrimination of progressive disease (PD) from radiation necrosis (RN) in patients with gliomas. Previous literature showed that the combined use of FET-PET and MRI-PWI is advantageous; hhowever the increased diagnostic performances were only modest compared to the use of a single modality. Hence, the goal of this study was to further explore the benefit of combining MRI-PWI and [18F]FET-PET for differentiation of PD from RN...

Immune-checkpoint inhibitors (ICIs) play an important role in the treatment of cancers. However, immunotherapy can also induce atypical response patterns, including pseudoprogression, which is challenging to clinicians. We reported a case of non-small-cell lung cancer showing so-called pseudoprogression during the treatment of pembrolizumab and the patient benefited clinically from continued treatment with ICIs. Therefore, beside imaging evaluation, the assessment of Eastern Cooperative Oncology Group performance status score, numerical rating scale score of cancer pain, tumor markers levels, and neutrophil-to-lymphocyte ratio should be used for response evaluation of tumors in the era of immunotherapy...

Chimeric antigen receptor T-cell therapy (CAR-T) has been widely applied in the clinical practice of relapse/refractory (R/R) diffuse large B-cell lymphoma (DLBCL) due to its promising effects. Hyperprogressive disease (HPD) has gained attention for rapid tumor progression and has become a therapeutic and prognostic challenge. Here, we present a patient who had suffered from several recurrences previously and controlled well with a very small tumor lesion left was infused with CD19/CD22 bispecific CAR-T, with no immune effector cell-associated neurotoxicity syndrome, or cytokine release syndrome observed...

BACKGROUND: Radiation-induced damage (RID) after radiotherapy (RT) of primary brain tumors and metastases can be challenging to clinico-radiographically distinguish from tumor progression. RID includes pseudoprogression and radiation necrosis; the latter being irreversible and often associated with severe symptoms. While histopathology constitutes the diagnostic gold standard, biopsy-controlled clinical studies investigating RID remain limited. Whether certain brain areas are potentially more vulnerable to RID remains an area of active investigation...