Management of infliximab refractory immune checkpoint inhibitor gastrointestinal toxicity: a multicenter case series.

BACKGROUND: Immune checkpoint inhibitor (ICI) gastrointestinal toxicity (gastritis, enteritis, colitis) is a major cause of morbidity and treatment-related death. Guidelines agree steroid-refractory cases warrant infliximab, however best management of infliximab-refractory ICI gastrointestinal toxicity (IRIGItox) is unknown. METHODS: We conducted an international multicenter retrospective case series. IRIGItox was defined as failure of symptom resolution ≤grade 1 (Common Terminology Criteria for Adverse Events V.5.0) following ≥2 infliximab doses or failure of symptom resolution ≤grade 2 after one dose. Data were extracted regarding demographics, steroid use, response to treatment, and survival outcomes. Toxicity was graded at symptom onset and time of infliximab failure. Efficacy of infliximab refractory therapy was assessed by symptom resolution, time to resolution and steroid wean duration. Survival outcomes were examined based on immunosuppressive therapy received. RESULTS: 78 patients were identified: median age 60 years; 56% men; majority melanoma (N=70, 90%); 60 (77%) received anti-cytotoxic T-lymphocyte-associated protein 4 alone or in combination with anti-programmed cell death protein-1 and most had colitis (N=74, 95%). 106 post-infliximab treatments were given: 31 calcineurin inhibitors (CNIs); 27 antimetabolites (mycophenolate, azathioprine); 16 non-systemic immunomodulatory agents (eg, mesalazine or budesonide); 15 vedolizumab; 5 other biologics (anti-interleukin-12/23, 16, Janus kinase inhibitors) and 7 interventional procedures (including colectomy); 5 did not receive post-infliximab therapy. Symptom resolution was achieved in most (N=23/31, 74%) patients treated with CNIs; 12/27 (44%) with antimetabolites; 7/16 (44%) with non-systemic immunomodulation, 8/15 (53%) with vedolizumab and 5/7 (71%) with interventional procedures. No non-vedolizumab biologics resulted in toxicity resolution. CNIs had the shortest time to symptom resolution (12 days) and steroid wean (43 days); however, were associated with poorer event-free survival (6.3 months) and overall survival (26.8 months) than other agents. Conversely, vedolizumab had the longest time to toxicity resolution and steroid wean, 66 and 124 days, but most favorable survival data: EFS 24.5 months; median OS not reached. Six death occurred (three due to IRIGItox or management of toxicity; three with persisting IRIGItox and progressive disease). CONCLUSIONS: IRIGItox causes major morbidity and mortality. Management is heterogeneous. CNIs appear most likely to result in toxicity resolution in the shortest time period, however, are associated with poorer oncological outcomes in contrast to vedolizumab.

A Retrospective Multi-Institutional Cohort Analysis of Clinical Characteristics and Outcomes in Dedifferentiated Chondrosarcoma.

BACKGROUND: Dedifferentiated chondrosarcoma (DDCS) is a rare subset of chondrosarcoma. It is an aggressive neoplasm characterized by a high rate of recurrent and metastatic disease with overall poor outcomes. Systemic therapy is often used to treat DDCS; however, the optimal regimen and timing are not well defined, with current guidelines recommending following osteosarcoma protocols. METHODS: We conducted a multi-institutional retrospective analysis of clinical characteristics and outcomes of patients with DDCS. Between 1 January 2004 and 1 January 2022, the databases from five academic sarcoma centers were reviewed. Patient and tumor factors, including age, sex, tumor size, site, location, the treatments rendered, and survival outcomes, were collected. RESULTS: Seventy-four patients were identified and included in the analysis. Most patients presented with localized disease. Surgical resection was the mainstay of therapy. Chemotherapy was used predominantly in the metastatic setting. Partial responses were low (n = 4; 9%) and occurred upon treatment with doxorubicin with cisplatin or ifosfamide and single-agent pembrolizumab. For all other regimens, stable disease was the best response. Prolonged stable disease occurred with the use of pazopanib and immune checkpoint inhibitors. CONCLUSIONS: DDCS has poor outcomes and conventional chemotherapy has limited benefit. Future studies should focus on defining the possible role of molecularly targeted therapies and immunotherapy in the treatment of DDCS.

Sotrovimab restores neutralization against current Omicron subvariants in patients with blood cancer.

Wu et al. report that patients with hematologic malignancies have reduced immunity against SARS-CoV-2 Omicron subvariants and Sotrovimab retains neutralizing capacity against all tested Omicron subvariants.

Hyperglycaemia following immune checkpoint inhibitor therapy-Incidence, aetiology and assessment.

AIMS: We systematically studied the presence of hyperglycaemia during treatment with Immune Checkpoint Inhibitors (ICPI) for cancer, in those with and without diabetes at baseline, and determined the cause of new-onset hyperglycaemia, METHODS: Retrospective review of electronic records of those receiving an ICPI for melanoma, lung or renal cancer. RESULTS: Overall, 959 participants were included. In this study, 103 had diabetes at baseline (10.7%). Those with lung cancer had the highest frequency of diabetes; 131 people had hyperglycaemia (defined as at least one glucose ≥11.1 mmol/L) in the year after starting an ICPI. The incidence was 55% in those with diabetes at baseline, and 8.6% in those without baseline diabetes. Among 74 with new-onset hyperglycaemia (without pre-existing diabetes) 76% was attributable to steroid induced diabetes, with 9.5% due to ICPI Induced diabetes resembling type 1 diabetes. CONCLUSIONS: Hyperglycaemia is common in persons receiving an ICPI for cancer, including 8.6% of those without known diabetes. While much of this is due to glucocorticoid use, care is needed to avoid missing those with ICPI-induced diabetes who are at risk of diabetic ketoacidosis, which is a medical emergency.

Functional immune responses against SARS-CoV-2 variants of concern after fourth COVID-19 vaccine dose or infection in patients with blood cancer.

Patients with blood cancer continue to have a greater risk of inadequate immune responses following three COVID-19 vaccine doses and risk of severe COVID-19 disease. In the context of the CAPTURE study (NCT03226886), we report immune responses in 80 patients with blood cancer who received a fourth dose of BNT162b2. We measured neutralizing antibody titers (NAbTs) using a live virus microneutralization assay against wild-type (WT), Delta, and Omicron BA.1 and BA.2 and T cell responses against WT and Omicron BA.1 using an activation-induced marker (AIM) assay. The proportion of patients with detectable NAb titers and T cell responses after the fourth vaccine dose increased compared with that after the third vaccine dose. Patients who received B cell-depleting therapies within the 12 months before vaccination have the greatest risk of not having detectable NAbT. In addition, we report immune responses in 57 patients with breakthrough infections after vaccination.

Early response evaluation using 18F-FDG-PET/CT does not influence management of patients with metastatic gastrointestinal stromal tumors (GIST) treated with palliative intent.

AIM: The aim of this study was to investigate the impact of 18F-FDG-PET/CT on treatment decision making in metastatic gastrointestinal stromal tumor (GIST) patients. METHODS: This study retrospectively evaluated 18F-FDG-PET/CT scans to monitor response of metastatic GIST patients treated with palliative intent. Data from the Dutch GIST Registry was used. Early scans (<10 weeks after start of treatment) and late scans (>10 weeks after start of treatment) were scored on the impact in change of treatment. RESULTS: Sixty-one PET/CT scans were performed for treatment evaluation in 39 patients with metastatic GIST of which 36 were early scans and 25 were late scans. Early PET/CT scans led to a change in management in 5.6% of patients and late PET/CT scans led to a change in management in 56% of patients. Change in management was more often seen after scans with lack of metabolic response (48% vs. 11% in scans with metabolic response, p=0.002). Neither metabolic response nor change in treatment were more often seen in patients with KIT mutations compared to patients with non-KIT mutations (metabolic response 65% KIT vs. 46% non-KIT, p=0.33, and change in management 28% KIT vs. 21% non-KIT, p=0.74). CONCLUSION: 18F-FDG-PET/CT is not recommended for early response evaluation in an unselected patient population with metastatic GIST, since it does not influence treatment decisions. 18F-FDG-PET/CT, however, can be useful for late response assessment, especially in case of indeterminate CT results.

Clinicopathological features and treatment outcome of oesophageal gastrointestinal stromal tumour (GIST): A large, retrospective multicenter European study.

BACKGROUND: Oesophageal gastrointestinal stromal tumours (GISTs) account for ≤1% of all GISTs. Consequently, evidence to guide clinical decision-making is limited. METHODS: Clinicopathological features and outcomes in patients with primary oesophageal GIST from seven European countries were collected retrospectively. RESULTS: Eighty-three patients were identified, and median follow up was 55.0 months. At diagnosis, 59.0% had localized disease, 25.3% locally advanced and 13.3% synchronous metastasis. A biopsy (Fine Needle aspiration n = 29, histological biopsy n = 31) was performed in 60 (72.3%) patients. The mitotic count was low (<5 mitoses/50 High Power Fields (HPF)) in 24 patients and high (≥5 mitoses/50 HPF) in 27 patients. Fifty-one (61.4%) patients underwent surgical or endoscopic resection. The most common reasons to not perform an immediate resection (n = 31) were; unresectable or metastasized GIST, performance status/comorbidity, patient refusal or ongoing neo-adjuvant therapy. The type of resections were enucleation (n = 11), segmental resection (n = 6) and oesophagectomy with gastric conduit reconstruction (n = 33), with median tumour size of 3.3 cm, 4.5 cm and 7.7 cm, respectively. In patients treated with enucleation 18.2% developed recurrent disease. The recurrence rate in patients treated with segmental resection was 16.7% and in patients undergoing oesophagectomy with gastric conduit reconstruction 36.4%. Larger tumours (≥4.0 cm) and high (>5/5hpf) mitotic count were associated with worse disease free survival. CONCLUSION: Based on the current study, enucleation can be recommended for oesophageal GIST smaller than 4 cm, while oesophagectomy should be preserved for larger tumours. Patients with larger tumours (>4 cm) and/or high mitotic count should be treated with adjuvant therapy.

Health-Related Quality of Life and Experiences of Sarcoma Patients during the COVID-19 Pandemic.

Sarcomas are rare cancers with a spectrum of clinical needs and outcomes. We investigated care experiences and health-related quality of life (HRQoL) in sarcoma patients during the COVID-19 pandemic. Patients with appointments during the first two months of the UK lockdown were invited to complete a survey. Questions included views on care modifications, COVID-19 worry and psychosocial impact, and EORTC-QLQ-C30 items. 350 patients completed the survey; median age 58 (16-92) years. Care modifications included telemedicine (74%) and postponement of appointments (34%), scans (34%) or treatment (10%). Most felt the quality of care was not affected (72%), however, social life (87%) and emotional wellbeing (41%) were affected. Worry about COVID-19 infection was moderately high (mean 5.8/10) and significantly related to higher cancer-related worry; associated with lower emotional functioning irrespective of treatment intent. Curative patients (44%) with low resilient coping scores had significantly higher COVID-19 worry. Patients who did not know their treatment intent (22%) had significantly higher COVID-19 worry and insomnia. In summary, care experiences were generally positive; however, cancer-related worry, low resilient coping and uncertainty about treatment intent were associated with COVID-19 worry. These patients may benefit from additional psychological support during the pandemic and beyond.

Telemedicine During the COVID-19 Pandemic: Impact on Care for Rare Cancers.

PURPOSE: Many patients with cancer, often those with rare cancers such as sarcomas, travel long distances to access expert care. The COVID-19 pandemic necessitated widespread changes in delivery of cancer care, including rapid adoption of telemedicine-based care. We aimed to evaluate the impact of telemedicine on patients, clinicians, and care delivery at the Royal Marsden Hospital (RMH) Sarcoma Unit during the pandemic. METHODS: Data were extracted from patient records for all planned outpatient appointments at the RMH Sarcoma Unit from March 23 to April 24, 2020. Patients and clinicians completed separate questionnaires to understand their experiences. RESULTS: Of 379 planned face-to-face appointments, 283 (75%) were converted to telemedicine. Face-to-face appointments remained for patients who needed urgent start of therapy or performance status assessment. Patients lived on average > 1.5 hours from RMH. Patient satisfaction (n = 108) with telemedicine was high (mean, 9/10), and only 48% (n = 52/108) would not want to hear bad news using telemedicine. Clinicians found telemedicine efficient, with no associated increased workload, compared with face-to-face appointments. Clinicians indicated lack of physical examination did not often affect care provision when using telemedicine. Most clinicians (n = 17; 94%) believed telemedicine use was practice changing; congruently, 80% (n = 86/108) of patients desired some telemedicine as part of their future care, citing reduced cost and travel time. CONCLUSION: Telemedicine can revolutionize delivery of cancer care, particularly for patients with rare cancers who often live far away from expert centers. Our study demonstrates important patient and clinician benefits; assessment of longer-term impact on patient outcomes and health care systems is needed.

Revolutions in treatment options in gastrointestinal stromal tumours (GISTs): the latest updates

OPINION STATEMENT: The treatment of advanced GIST is rapidly evolving with the development of novel molecular compounds such as avapritinib and ripretinib, but also promising results have been achieved with cabozantinib in a phase II trial. The availability of over five lines of treatment for patients with advanced GIST is likely to completely shift the current second-line and third-line treatment options, and will also potentially enable a personalised approach to treatment. Imatinib will most likely remain as the first-line treatment of choice for the vast majority of GIST patients. However, for GIST patients with tumours harbouring a D842V mutation in PDGFRA exon 18, avapritinib has shown efficacy and will become first-line therapy for this molecular subgroup. For second- and third-line treatment, results are awaited of a number of clinical trials. However, second-line and further treatment could potentially be tailored depending on secondary mutations found in imatinib-resistant GISTs. As secondary resistance to TKIs remains the biggest challenge in the treatment of GIST and despite negative results with alternating regimens in phase II, combination treatments should be further evaluated to tackle this issue. Moreover, the favourable safety profiles observed with avapritinib and ripretinib suggest that combination treatments are feasible, for instance, combining two TKIs or a TKI with drugs targeting downstream signalling pathways, such as PI3K inhibitors or MEK inhibitors. Finally, in line with further personalisation of treatment in GIST, a multidisciplinary approach is essential, and local treatment options, such as RFA, resection in case of unifocal progression, and radiotherapy, should be considered.

Toxicity management of regorafenib in patients with gastro-intestinal stromal tumour (GIST) in a tertiary cancer centre.

BACKGROUND: Regorafenib is a multi-kinase inhibitor approved as third line treatment for metastatic GIST. Dose limiting toxicities are frequently seen and many patients require dose reductions. This study aimed to evaluate regorafenib toxicities and their management in a real-world GIST population. METHODS: Retrospective review of a prospectively maintained database identified 50 patients with GIST treated with regorafenib at our centre between March 2013 and September 2018. RESULTS: Median progression free survival (PFS) was 7.7 months [interquartile range (IQR) 2.8-14.4 months]. Median overall survival (OS) from start of regorafenib to death or last follow up was 15.7 months (IQR 9.2-28.4 months). Baseline median Eastern Cooperative Oncology Group (ECOG) performance status on starting regorafenib was 1. The main reason for discontinuing regorafenib was progressive disease (PD) (31/50 [62%]) rather than toxicity (10/50 [20%]). Grade 3-4 adverse events (AEs) were seen in 23/50 (46%) patients; palmar-plantar erythrodysesthesia (PPE) was most frequently seen (9/50 (18%)). Two patients died whilst on treatment with regorafenib from multi-organ failure secondary to sepsis (4%). Dose reductions were required in 19/50 patients (38%) and 8/50 (16%) patients started regorafenib at a lower dose band than the recommended dose (160 mg) due to comorbidities or concern over a higher individual risk of toxicity. CONCLUSION: Although PD was the main reason for discontinuing treatment, toxicity management and dosing of regorafenib remains critical. Median duration of treatment was longer compared to previous studies suggesting a durable clinical benefit with regorafenib with rigorous toxicity management.

A single digital droplet PCR assay to detect multiple KIT exon 11 mutations in tumor and plasma from patients with gastrointestinal stromal tumors.

BACKGROUND: Gastrointestinal stromal tumors (GISTs) are characterized by oncogenic KIT mutations that cluster in two exon 11 hotspots. The aim of this study was to develop a single, sensitive, quantitative digital droplet PCR (ddPCR) assay for the detection of common exon 11 mutations in both GIST tumor tissue and in circulating tumor DNA (ctDNA) isolated from GIST patients' plasma. METHODS: A ddPCR assay was designed using two probes that cover both hotspots. Available archival FFPE tumor tissue from 27 consecutive patients with known KIT exon 11 mutations and 9 randomly selected patients without exon 11 mutations were tested. Plasma samples were prospectively collected in a multicenter bio-databank from December 2014. ctDNA was analyzed of 22 patients with an exon 11 mutation and a baseline plasma sample. RESULTS: The ddPCR assay detected the exon 11 mutation in 21 of 22 tumors with exon 11 mutations covered by the assay. Mutations in ctDNA were detected at baseline in 13 of 14 metastasized patients, but in only 1 of 8 patients with localized disease. In serial plasma samples from 11 patients with metastasized GIST, a decrease in mutant droplets was detected during treatment. According to RECIST 1.1, 10 patients had radiological treatment response and one patient stable disease. CONCLUSION: A single ddPCR assay for the detection of multiple exon 11 mutations in ctDNA is a feasible, promising tool for monitoring treatment response in patients with metastasized GIST and should be further evaluated in a larger cohort.

Early Evaluation of Response Using 18F-FDG PET Influences Management in Gastrointestinal Stromal Tumor Patients Treated with Neoadjuvant Imatinib.

18F-FDG PET has previously been proven effective as an early way to evaluate the response of gastrointestinal stromal tumors (GISTs) to imatinib treatment. However, it is unclear whether early evaluation of response affects treatment decisions in GIST patients treated with neoadjuvant intent. Methods: We retrospectively scored changes in management based on early evaluation of response by 18F-FDG PET in patients in the Dutch GIST registry treated with neoadjuvant imatinib. Results: Seventy 18F-FDG PET scans were obtained for 63 GIST patients to evaluate for an early response to neoadjuvant imatinib. The scans led to a change in management in 27.1% of the patients. Change in management correlated strongly with lack of metabolic response (P < 0.001) and non-KIT exon 11-mutated GISTs (P < 0.001). Conclusion: Performing 18F-FDG PET for early evaluation of response often results in a change of management in GIST patients harboring the non-KIT exon 11 mutation and should be considered the standard of care in GIST patients treated with neoadjuvant intent.

Elderly patients with gastrointestinal stromal tumour (GIST) receive less treatment irrespective of performance score or comorbidity - A retrospective multicentre study in a large cohort of GIST patients.

OBJECTIVE: Although gastrointestinal stromal tumours (GIST) predominantly occur in older patients, data on treatment patterns in elderly GIST patients are scarce. METHODS: Patients registered in the Dutch GIST Registry (DGR) from January 2009 until December 2016 were included. Differences in treatment patterns between elderly (≥75 years) and younger patients were compared. Multivariate analyses were conducted using logistic regression. RESULTS: Data of 145 elderly and 665 non-elderly patients were registered (median age 78 and 60 years respectively). In elderly patients, performance score (WHO-PS) and age-adjusted Charlson comorbidity index (ACCI) were significantly higher (p < 0.05; p < 0.001), and albumin level significantly lower (p = 0.04). Hundred-and-nine (75.2%) elderly and 503 (75.6%) non-elderly patients had only localised disease. Surgery was performed in 57% of elderly versus 84% of non-elderly patients (p = 0.003, OR: 0.26, 95% CI: 0.11-0.63). No differences in surgery outcome or complications were found. Thirty-eight percent of elderly with an indication for adjuvant treatment did receive imatinib versus 68% of non-elderly (p = 0.04, OR: 0.47, 95% CI: 0.23-0.95). Thirty-six elderly and 162 non-elderly patients had metastatic disease. Palliative imatinib was equally given (mean dose 400 mg) and adverse events were mostly minor (p = 0.71). In elderly, drug-related toxicity was in 32.7% reason to discontinue imatinib versus 5.1% in non-elderly (p = 0.001, OR 13.5, 95% CI: 2.8-65.0). Median progression-free survival (PFS) was 24 months in elderly and 33 months in non-elderly (p = 0.10). Median overall survival (OS) was 34 months and 59 months respectively (p = 0.01). CONCLUSIONS: Elderly GIST patients with localised disease receive less surgery and adjuvant treatment, irrespective of comorbidity and performance score. Drug-related toxicity results more often in treatment discontinuation. This possibly results in poor outcome.

Clinical characteristics and treatment outcome in a large multicentre observational cohort of PDGFRA exon 18 mutated gastrointestinal stromal tumour patients.

PURPOSE: Patients, platelet-derived growth factor receptor alpha (PDGFRA) D842V-mutated gastrointestinal stromal tumours (GISTs) are known for their insensitivity to imatinib. However, in clinical practice responses have been observed in some patients. We describe the natural history and treatment outcomes in a cohort of PDGFRA exon 18 mutated GIST patients. PATIENTS AND METHODS: A retrospective cohort study was conducted in PDGFRA exon 18 mutation GIST patients treated in six expert centres in the Netherlands and the United States. Two independent radiologists assessed radiological response to imatinib according to Choi's criteria in all patients with measurable disease treated with imatinib in neo-adjuvant or palliative intent. RESULTS: Seventy-one patients with PDGFRA exon 18 mutation were identified of whom 48 patients (69%) had a D842V mutation. Twenty-two (45.8%) D842V-mutated GIST patients received imatinib treatment, 16 had measurable disease. Fourteen out of the 23 (60.9%) patients with non-D842V mutations received imatinib treatment, eight had measurable disease. Two out of 16 (12.5%) D842V-mutated GIST patients had partial response, 3 patients (18.8%) had stable disease and 9 patients (56.3%) had progressive disease as best response. Two patients did not have follow-up computed tomography scans to assess response. Six out of 8 (75%) patients with non-D842V exon 18 mutations had partial response and two (25%) had stable disease as best response. CONCLUSION: Patients with D842V-mutated GISTs can occasionally respond to imatinib. In the absence of better therapeutic options, imatinib should therefore not be universally withheld in patients with this mutation.

Imatinib Pharmacokinetics in a Large Observational Cohort of Gastrointestinal Stromal Tumour Patients.

BACKGROUND: Low trough imatinib concentration (C min) values have been associated with poor clinical outcomes in gastrointestinal stromal tumour (GIST) patients. This study describes the pharmacokinetics of imatinib in a large cohort of GIST patients in routine clinical care. METHODS: An observational study was performed in imatinib-treated GIST patients. Patient and tumour characteristics were derived from the Dutch GIST Registry and medical records. Imatinib concentrations were measured by liquid chromatography with tandem mass spectrometry. The analyses included the occurrence of a low imatinib C min (<1000 µg/L), the change in the C min over time and the correlation between exposure and response. RESULTS: In total, 421 plasma samples were available from 108 GIST patients. Most patients (79.6 %) received an imatinib dose of 400 mg. The inter- and intrapatient variabilities in C min were 54 and 23 %, respectively. In the first steady-state sample, 44.4 % of patients presented with C min values <1000 µg/L; 32.4 % of patients had values <1000 µg/L in >75 % of their samples. Only 33.3 % of patients had C min values ≥1000 µg/L in all measured samples. No decrease in C min over time was found (P > 0.05). Fifty-seven (91.9 %) of 62 palliative-treated patients had a tumour response (median C min 1271 µg/L). Five palliative patients (8.1 %) did not respond (median C min 920 µg/L). Given the limited number of non-responders in this cohort, no statistically significant association with clinical benefit could be demonstrated. CONCLUSION: In routine clinical care, one third of GIST patients are systematically underexposed with a fixed dose of imatinib. Prospective clinical studies are needed to investigate the value of C min-guided imatinib dosing in GIST patients.

Imatinib-induced agranulocytosis in patients with gastrointestinal stromal tumors.

Agranulocytosis is a rare but serious side effect of imatinib in gastrointestinal stromal tumor (GIST) patients. Imatinib is an inhibitor of the proto-oncogene tyrosine kinase (c-kit) and the first-line agent in patients with locally advanced and metastatic GIST. Little evidence is available on the management of this adverse event, and consensus-based guidelines are lacking. In this article, we describe 4 patients with agranulocytosis after starting imatinib. In addition, an overview of the available literature concerning the underlying mechanisms is given, and therapeutic strategies for overcoming this adverse event are discussed. In our experience it appears safe to restart imatinib after normalization of neutrophil count. In case of relapse of agranulocytosis, reintroduction combined with prednisolone, with treatment with granulocyte colony-stimulating factor or dose reduction can be considered.