• Mucormycosis infection in the upper limb: A salvageable condition.

      Salibi, Andrej; McArdle, C; Morritt, A; The Christie NHS Foundation Trust, Wilmslow Road, Manchester, M20 3DL. (2017-07-24)
    • Mucosal melanoma of the head and neck: radiotherapy or surgery?

      Douglas, Catriona Mairi; Malik, Tass; Swindell, Ric; Lorigan, Paul C; Slevin, Nicholas J; Homer, Jarrod J; Department of Head and Neck Surgery, Christie Hospital, Manchester, United Kingdom. (2010-08)
      INTRODUCTION: Head and neck mucosal melanoma (MuM) is rare, comprising < 1% of all melanomas in Western Europe. METHODS: A retrospective analysis of case records of patients treated between 1965 and 2001 was carried out. (Survival outcomes were obtained from the case notes and cancer registry.) The median age of the 68 patients was 63 years (range 29-86 years). Thirty-nine percent were male, and 61% were female. (The minimum follow-up time was 15 months.) The two most common primary sites were the sinonasal complex (65%) and oral cavity (19%). Twenty-one percent of patients presented with metastases (nodal or distant). Fifty-five patients were treated with curative intent: 30 patients with primary radiotherapy and 25 patients with surgery +/- postoperative radiotherapy. RESULTS: The overall survival was 22% at 5 years, and the cancer-specific survival was 32% at 5 years. CONCLUSION: MuM has a poor overall prognosis. Poor prognostic indicators are site at presentation and presentation with metastasis. This series is unique in that a significant proportion of patients were given primary radiotherapy as definitive treatment. Surgery may have advantages, particularly for oral cavity MuM. In contrast to previous reports, definitive radiotherapy is worthy of consideration as curative treatment.
    • Multi-Center Randomized Phase II Study Comparing Cediranib plus Gefitinib with Cediranib plus Placebo in Subjects with Recurrent/Progressive Glioblastoma.

      Brown, N; McBain, Catherine A; Nash, S; Hopkins, K; Sanghera, P; Saran, F; Phillips, M; Dungey, F; Clifton-Hadley, L; Wanek, K; et al. (2016)
      Cediranib, an oral pan-vascular endothelial growth factor (VEGF) receptor tyrosine kinase inhibitor, failed to show benefit over lomustine in relapsed glioblastoma. One resistance mechanism for cediranib is up-regulation of epidermal growth factor receptor (EGFR). This study aimed to determine if dual therapy with cediranib and the oral EGFR inhibitor gefitinib improved outcome in recurrent glioblastoma.
    • Multi-centre analysis of cardiac events following radical radiotherapy for lung cancer

      Sun, F; Banfill, Kathryn; Lilley, J; Wheller, B; Murray, L; McWilliam, Alan; van Herk, Marcel; Abravan, Azadeh; Faivre-Finn, Corinne; Franks, K; et al. (2019)
    • Multi-centre analysis of cardiac events following radical radiotherapy for lung cancer

      Sun, F; Banfill, Kathryn; Lilley, J; Wheller, B; Murray, L; McWilliam, Alan; van Herk, Marcel; Abravan, Azadeh; Faivre-Finn, Corinne; Franks, K; et al. (2019)
      Background: Radical radiotherapy (RRT) plays an essential role in the management of early and locally advanced lung cancer. Recent studies suggest cardiac events post radiotherapy worsen survival outcome for patients. This study aims to identify risk factors which predispose patients to cardiac events post radiotherapy. Methods: All patients who received RRT (including Stereotactic Body Radiotherapy (SBRT), radical fractionated radiotherapy and chemoradiotherapy) for lung cancer between 01/01/2010 to 30/12/2016 at 2 UK institutions have been included. Patients were excluded if they had multiple courses of radiotherapy to the chest. Individual patient clinical information has been retrieved from hospital electronic database. Patient and cancer demographics have been collected. Pre-existing cardiac conditions, Charlsons’ Co-morbidity index and Qrisk 3 scores were calculated. Post radiotherapy cardiac events were identified rom electronic patient records and time to cardiac events were calculated. Results: 600 patients have been identified so far and processed. Median follow up is 31 months. Of all patients, 29% had pre-existing cardiac conditions. 52 patients experienced cardiac events following radiotherapy, of which 37% were ischaemic events. Of patients who experienced an ischaemic event, 58% did not have a known pre-existing cardiac condition. 71% of cardiac events post RRT occurred in the first 2 years following RT. Proportionally, patients who underwent radical fractionated radiotherapy and concurrent chemoradiotherapy had the highest incidence of cardiac events. Patient characteristics of those who experienced cardiac toxicity are summarized in the table below.
    • A multi-centre phase I trial of the PARP inhibitor olaparib in patients with relapsed chronic lymphocytic leukaemia, T-prolymphocytic leukaemia or mantle cell lymphoma.

      Pratt, G; Yap, C; Oldreive, C; Slade, D; Bishop, R; Griffiths, M; Dyer, M; Fegan, C; Oscier, D; Pettitt, A; et al. (2017-06-23)
    • Multi-centre technical evaluation of the radiation-induced lymphocyte apoptosis assay as a predictive test for radiotherapy toxicity

      Talbot, C; Veldwijk, M; Azria, D; Batini, C; Bierbaum, M; Brengues, M; Chang-Claude, J; Johnson, K; Keller, A; Smith, S; et al. (2019)
      Predicting which patients will develop adverse reactions to radiotherapy is important for personalised treatment. Prediction will require an algorithm or nomogram combining clinical and biological data. The radiation-induced lymphocyte apoptosis (RILA) assay is the leading candidate as a biological predictor of radiotherapy toxicitY In this study we tested the potential of the assay for standardisation and use in multiple testing laboratories. The assay was standardised and reproducibility determined using samples from healthy volunteers assayed concurrently in three laboratories in Leicester (UK), Mannheim (Germany) and Montpellier (France). RILA assays were performed on samples taken prior to radiotherapy from 1319 cancer patients enrolled in the REQUITE project at multiple centreS The patients were being treated for breast (n=753), prostate (n=506) or lung (n=60) cancer. Inter-laboratory comparisons identified several factors affecting RESULTS: storage time, incubation periods and type of foetal calf serum. Following standardisation, there was no significant difference in results between the centreS Significant differences were seen in RILA scores between cancer types (prostate>breast>lung), by smoking status (non-smokers>smokers) and co-morbidity with rheumatoid arthritis (arthritics>non-arthritics). An analysis of acute radiotherapy toxicity showed as expected that RILA assay does not predict most end-points, but unexpectedly did predict acute breast pain. This result may elucidate the mechanism by which the RILA assay predicts late radiotherapy toxicity. The work shows clinical trials involving multiple laboratory measurement of the RILA assay are feasible and the need to account for tumour type and other variables when applying to predictive models.
    • Multi-institutional dosimetric delivery assessment of intracranial stereotactic radiosurgery on different treatment platforms

      Dimitriadis, A.; Tsang, Y.; Thomas, R. A. S.; Palmer, A. L.; Eaton, D.; Lee, J.; Patel, R.; Silvestre Patallo, I.; Gouldstone, C.; Snaith, J. A. D.; et al. (2020)
      BACKGROUND AND PURPOSE: Assessment of dosimetric accuracy of radiosurgery on different treatment platforms. MATERIAL AND METHODS: Thirty-three single fraction treatment plans were assessed at thirty centres using an anthropomorphic head phantom with target and brainstem structures. The target being a single irregular shaped target, ~8 cc, 10 mm from the brainstem. The phantom was 'immobilised', scanned, planned and treated following the local protocols. EBT-XD films and alanine pellets were used to measure absolute dose, inside both the target and the brainstem, and compared with TPS predicted dose distributions. RESULTS: PTV alanine measurements from gantry-based linacs showed a median percentage difference to the TPS of 0.65%. Cyberknife (CK) had the highest median difference of 2.3% in comparison to the other platforms. GammaKnife (GK) showed the smallest median of 0.3%. Similar trends were observed in the OAR with alanine measurements showing median percentage differences of1.1%, 2.0% and 0.4%, for gantry-based linacs, CK and GK respectively. All platforms showed comparable gamma passing rates between axial and sagittal films. CONCLUSIONS: This comparison has highlighted the dosimetric variation between measured and TPS calculated dose for each delivery platform. The results suggest that clinically acceptable agreement with the predicted dose distributions is achievable by all treatment delivery systems.
    • A multi-institutional dosimetry audit of rotational intensity-modulated radiotherapy.

      Clark, C; Hussein, M; Tsang, Y; Thomas, R; Wilkinson, D; Bass, G; Snaith, J; Gouldstone, C; Bolton, Steve; Nutbrown, R; et al. (2014-11)
      Rotational IMRT (VMAT and Tomotherapy) has now been implemented in many radiotherapy centres. An audit to verify treatment planning system modelling and treatment delivery has been undertaken to ensure accurate clinical implementation.
    • Multi-level evidence that circulating CK18 is a biomarker of tumour burden in colorectal cancer.

      Greystoke, Alastair; Dean, Emma J; Saunders, Mark P; Cummings, Jeffrey; Hughes, A; Ranson, Malcolm R; Dive, Caroline; Renehan, Andrew G; Clinical and Experimental Pharmacology (CEP) Group, Paterson Institute for Cancer Research, University of Manchester, Manchester, UK. (2012-10-23)
      Background:Circulating total cytokeratin 18 (tCK18) and/or caspase cleaved cytokeratin 18 (cCK18) (measured by M65 and M30 enzyme-linked immunosorbent assays (ELISAs), respectively) are used as pharmacodynamic (PD) biomarkers of epithelial cell death in clinical trials. Having validated these ELISAs, we assessed their utility in colorectal cancer (CRC).Methods:We applied the assays in several settings: 53 controls; 97 patients undergoing surgery and 74 patients with metastatic CRC undergoing chemotherapy (55 first line; 56 patients with repeated sampling through chemotherapy). Prognostic significance was evaluated using Kaplan-Meier life tables and Cox models; PD utility was assessed by analysis of repeated measures.Results:Median cCK18 and tCK18 levels were elevated in patients with cancer (both P=0.0001), and among cancer patients, there were increasing trends from early to advanced stages (both P(trends)=0.0001). Increasing tCK18 predicted for reduced survival after surgery with curative intent (adjusted hazard ratio (HR) for doubling in concentration 1.77, 95% CI: 1.04, 3.01) and after first-line chemotherapy in metastatic disease (adjusted HR per doubling in concentration=1.78, 95% CI: 1.37, 2.30). In patients with progressive disease during chemotherapy, repeated sampling revealed profiles with high baselines and progressive upwardly increases after cycle 1.Conclusion:This study provides evidence for cytokeratin 18 (CK18) as a prognostic and PD biomarker in patients with CRC and supports continued deployment of circulating CK18 in biomarker-enhanced trials.
    • Multi-maintenance olaparib in relapsed, platinum-sensitive BRCA-mutant high-grade serous ovarian carcinoma (MOLTO): A phase II feasibility study

      Morgan, Robert David; Clamp, Andrew R; Ryder, W. D. J.; Wheeler, C.; Buckley, E.; Truelove, J.; Murphy, A. D.; Hasan, Jurjees; Mitchell, Claire L; Burghel, G. J.; et al. (2021)
      Background Relapsed, platinum-sensitive high-grade serous ovarian carcinoma (RPS-HGSOC) is treated with platinum re-challenge. One course of olaparib maintenance monotherapy (OLAP1) improves PFS in RPS-HGSOC. It is unclear whether a second olaparib maintenance monotherapy course (OLAP2) in RPS-HGSOC following platinum re-challenge (PLAT2) is feasible. Methods Single centre, non-randomised, phase II study to determine feasibility of OLAP2 after response to PLAT2 in BRCAm RPS-HGSOC. Co-primary endpoints: 1) percentage of patients that started PLAT2 who received one dose of OLAP2 (N3/N2) and; 2) percentage of patients who received OLAP2+/-Cediranib ?6 months (N4/N3). Two trial entry points (EPs) pre-PLAT: 1) olaparib-na�ve (EP1, Pre-PLAT1) and; 2) OLAP1 pre-treated (EP2, Pre-PLAT2). If PFI ?6months on OLAP1, patient offered OLAP2. If PFI <6months on OLAP1, patient offered OLAP2+Cediranib. Results Between May 2017 and September 2019, 27 patients were enrolled (N1;EP1=17; EP2=10). BRCA1:BRCA2 22:5. Age range: 44-78 years. Three (median) lines of platinum chemotherapy prior to OLAP1. N=23 responded to PLAT1 and received OLAP1. N=18 received PLAT2 (N2) and N=11 achieved RECIST CR/PR/SD to PLAT2 and subsequently received OLAP2+/-Cediranib (N3/N2=61%). N=4 completed ?6 months OLAP2 (N4/N3=36%). Commonest grade 2-3 AEs during OLAP2 were anaemia (n=3 G2, n=1 G3), abdominal pain (n=1 G2, n=2 G3), fatigue (n=1 G2, n=2 G3), nausea (n=3 G2). No cases of AML/MDS, pneumonitis/ILD or new secondary malignancy were reported. Key efficacy endpoints in the table. Tumour and ctDNA HRD/CNV-based concurrent biomarker study will also be presented. Conclusions No new safety concerns with OLAP2. OLAP2 demonstrated modest efficacy compared to OLAP1.
    • Multi-modality radical intent treatment in synchronous oligometastatic non-small cell lung cancer: how many patients complete the full treatment regime recommended by the MDT?

      Cheng, A.; Craig, C.; Summers, Yvonne J; Taylor, Paul; Califano, Raffaele; Cove-Smith, Laura; Woolf, David K; Duerden, R.; Sharman, A.; Lyons, J.; et al. (2019)
      Introduction: Management of oligometastatic disease in non-small cell lung cancer (NSCLC) identified at initial diagnosis (synchronous) often provokes treatment dilemmas within multi-disciplinary teams (MDTs). Suitable patients are sometimes considered for multi-modality radical-intent treatment including systemic therapy and local treatment to both the metastasis and the primary tumour. We sought to assess how many patients complete all components of this multi-modality treatment when recommended in our MDT as a surrogate marker of appropriate patient selection and practice. Methods: A retrospective review of our electronic lung cancer MDT database at Wythenshawe Hospital, South Manchester, between April 2016 and April 2018. Synchronous oligometastatic NSCLC cases were defined as a single metastasis in a single organ. We recorded patient demographics, performance status, TNM staging, pathology, and site of oligometastasis. MDT recommended treatment was compared to treatment completed. Results: 1754 individual MDT cases were identified. Synchronous oligometastatic NSCLC was found in 26 (1.5%) patients (Table 1). Thirteen patients (50%) with a single metastasis were recommended to have multi-modality treatment. The remaining patients were recommended for palliative systemic therapy (31%, 8/26) and best supportive care (19%, 5/26). Of the 13 patients recommended for multi-modality treatment, 12 were offered chemotherapy prior to local therapies to the primary tumour and metastatic site. The exception was the treatment of a brain metastasis first prior to systemic therapy. 13 (69%) managed to complete their entire treatment pathway. Failure to complete the treatment regime was commonly due to rapid disease progression. Conclusion: Synchronous oligometastatic NSCLC represents a small fraction of our MDT discussions (1.5%). Our MDT recommends multimodality radical-intent treatment in half of these cases and twothirds of patients complete the full treatment course suggesting appropriate patient selection. Our standard practice appears to be systemic therapy first followed by local treatment to the metastatic site and primary tumour.
    • Multicellular 3D models of human breast tissue to replace rodent xenograft models in breast cancer research.

      Ashworth, J; Meade, K; Howell, Anthony; Zaia, J; Farnie, G; Merry, C; Stem Cell Glycobiology Group, Centre for Biomolecular Sciences, University of Nottingham, Nottingham (2017)
    • A multicenter comparison between Child Pugh and ALBI scores in patients treated with sorafenib for Hepatocellular Carcinoma.

      Edeline, J; Blanc, J; Johnson, P; Campillo-Gimenez, B; Ross, P; Ma, Y; King, J; Hubner, Richard A; Sumpter, K; Darby, S; et al. (2016-05-23)
      The ALBI grade was proposed as an objective means to evaluate liver function in patients with Hepatocellular Carcinoma (HCC). ALBI grade 1 vs 2 were proposed as stratification factors within the Child Pugh (CP) A class. However, the original publication did not provide comparison with the sub-classification by points (5 to 15) within the CP classification.
    • Multicenter experience of nonpegylated liposomal doxorubicin use in the management of metastatic breast cancer.

      Palmieri, C; Misra, Vivek; Januszewski, A; Yosef, H; Ashford, R; Keary, I; Davidson, N; Department of Medical Oncology, Charing Cross Hospital, Imperial College Healthcare NHS Trust, London, United Kingdom (2014-04)
      This study aimed to investigate the use of nonpegylated liposomal doxorubicin (NPLD) in the management of metastatic breast cancer (MBC) within routine UK clinical practice and to assess its efficacy and tolerability.
    • Multicenter phase II study of fludarabine phosphate for patients with newly diagnosed lymphoplasmacytoid lymphoma, Waldenström's macroglobulinemia, and mantle-cell lymphoma.

      Foran, James M; Rohatiner, Ama; Coiffier, Bertrand; Barbui, Tiziano; Johnson, Stephen A; Hiddemann, Wolfgang; Radford, John A; Norton, Andrew J; Tollerfield, Susan M; Wilson, Martin P; et al. (1999-02)
      PURPOSE: Fludarabine phosphate (F-AMP) has significant activity in follicular lymphoma and in B-cell chronic lymphatic leukemia, where it has demonstrated high complete response (CR) rates. Lymphoplasmacytoid (LPC) lymphoma, Waldenstrom's macroglobulinemia (WM), and mantle-cell lymphoma (MCL) also present with advanced-stage disease and are incurable with standard alkylator-based chemotherapy. A phase II trial was undertaken to determine the activity of F-AMP in patients newly diagnosed with these diseases. PATIENTS AND METHODS: Between 1992 and 1996, 78 patients (aged 18 to 75 years) received intravenous F-AMP (25 mg/m2/d for 5 days, every 4 weeks) until maximum response, plus two further cycles as consolidation. The primary end point was response rate; secondary end points included time to progression (TTP), duration of response, and overall survival (OS). RESULTS: Forty-four (62%) of 71 assessable patients had a response to F-AMP (LPC lymphoma, 63%; WM, 79%; MCL, 41%); the CR rate was 15%. At a median follow-up of 1.5 years, 19 of 44 responding patients have had progression of lymphoma; the median duration of response was 2.5 years. The median survival has not yet been reached. There was no significant difference in the duration of response or OS between patients with different histologies; TTP was shorter in patients with MCL (P = .015). Myelosuppression was relatively common, and the treatment-related mortality (TRM) was 5%, mostly associated with pancytopenia and infection. CONCLUSION: Single-agent fludarabine phosphate is active in previously untreated LPC lymphoma and WM, with only moderate activity in MCL. However, the CR rate is low, and the TRM is relatively high. Its role in combination chemotherapy remains to be demonstrated.
    • Multicenter phase II study of iodine-131 tositumomab for chemotherapy-relapsed/refractory low-grade and transformed low-grade B-cell non-Hodgkin's lymphomas.

      Vose, J M; Wahl, R L; Saleh, M; Rohatiner, Ama; Knox, S J; Radford, John A; Zelenetz, Andrew D; Tidmarsh, G F; Stagg, R J; Kaminski, M S; et al. (2000-03)
      PURPOSE: This multicenter phase II study evaluated the efficacy, dosimetry methodology, and safety of iodine-131 tositumomab in patients with chemotherapy-relapsed/refractory low-grade or transformed low-grade non-Hodgkin's lymphoma (NHL). PATIENTS AND METHODS: Patients received a dosimetric dose that consisted of 450 mg of anti-B1 antibody followed by 35 mg (5 mCi) of iodine-131 tositumomab. Serial total-body gamma counts were then obtained to calculate the patient-specific millicurie activity required to deliver the therapeutic dose. A therapeutic dose of 75 cGy total-body dose (attenuated to 65 cGy in patients with platelet counts of 101,000 to 149,000 cells/mm(3)) was given 7 to 14 days after the dosimetric dose. RESULTS: Forty-five of 47 patients were treated with a single dosimetric and therapeutic dose. Twenty-seven patients (57%) had a response. The response rate was similar in patients with low-grade (57%) or transformed low-grade (60%) NHL. The median duration of response was 9.9 months. Fifteen patients (32%) achieved a complete response (CR; 10 CRs and five clinical CRs), including five patients (50%) with transformed low-grade NHL. The median duration of CR was 19.9 months, and six patients have an ongoing CR. Treatment was well tolerated, with the principal toxicity being hematologic. The most common nonhematologic toxicities that were considered to be possibly related to the treatment included mild to moderate fatigue (32%), nausea (30%), fever (26%), vomiting (15%), infection (13%), pruritus (13%), and rash (13%). Additionally, one patient developed human-antimouse antibodies. CONCLUSION: Iodine-131 tositumomab produced a high overall response rate, and approximately one third of patients had a CR despite having chemotherapy-relapsed or refractory low-grade or transformed low-grade NHL.
    • Multicenter phase II study of lapatinib in patients with brain metastases from HER2-positive breast cancer.

      Lin, Nancy U; Diéras, Véronique; Paul, Devchand; Lossignol, Dominique; Christodoulou, Christos; Stemmler, Hans-Joachim; Roché, Henri; Liu, Minetta C; Greil, Richard; Ciruelos, Eva; et al. (2009-02-15)
      PURPOSE: Brain metastases develop in one third of patients with advanced HER2+ breast cancer. Effective therapy for patients with central nervous system (CNS) progression after cranial radiation is extremely limited and represents a major clinical challenge. Lapatinib, an epidermal growth factor receptor/HER2 inhibitor, was associated with regressions of CNS lesions in a small phase 2 trial. The current study was done to further evaluate the CNS activity of lapatinib. The study was later amended to allow patients who progressed on lapatinib the option of receiving lapatinib plus capecitabine. EXPERIMENTAL DESIGN: Eligible patients had HER2+ breast cancer, progressive brain metastases, prior trastuzumab, and cranial radiotherapy. The primary end point was CNS objective response, defined as >or=50% volumetric reduction of CNS lesion(s) in the absence of increasing steroid use, progressive neurologic signs and symptoms, or progressive extra-CNS disease. RESULTS: Two-hundred and forty-two patients entered the study. CNS objective responses to lapatinib were observed in 6% of patients. In an exploratory analysis, 21% of patients experienced a >or=20% volumetric reduction in their CNS lesions. An association was observed between volumetric reduction and improvement in progression-free survival and neurologic signs and symptoms. Of the 50 evaluable patients who entered the lapatinib plus capecitabine extension, 20% experienced a CNS objective response and 40% experienced a >or=20% volumetric reduction in their CNS lesions. CONCLUSIONS: This study confirms the modest CNS antitumor activity of lapatinib. Additional responses were observed with the combination of lapatinib and capecitabine. Further studies of lapatinib-based regimens for CNS metastases from HER2+ breast cancer are warranted.
    • A multicentre and multi-national evaluation of the accuracy of quantitative Lu-177 SPECT/CT imaging performed within the MRTDosimetry project

      Tran-Gia, J.; Denis-Bacelar, A. M.; Ferreira, K. M.; Robinson, Andrew P; Calvert, Nicholas; Fenwick, A. J.; Finocchiaro, D.; Fioroni, F.; Grassi, E.; Heetun, W.; et al. (2021)
      Purpose: Patient-specific dosimetry is required to ensure the safety of molecular radiotherapy and to predict response. Dosimetry involves several steps, the first of which is the determination of the activity of the radiopharmaceutical taken up by an organ/lesion over time. As uncertainties propagate along each of the subsequent steps (integration of the time-activity curve, absorbed dose calculation), establishing a reliable activity quantification is essential. The MRTDosimetry project was a European initiative to bring together expertise in metrology and nuclear medicine research, with one main goal of standardizing quantitative 177Lu SPECT/CT imaging based on a calibration protocol developed and tested in a multicentre inter-comparison. This study presents the setup and results of this comparison exercise. Methods: The inter-comparison included nine SPECT/CT systems. Each site performed a set of three measurements with the same setup (system, acquisition and reconstruction): (1) Determination of an image calibration for conversion from counts to activity concentration (large cylinder phantom), (2) determination of recovery coefficients for partial volume correction (IEC NEMA PET body phantom with sphere inserts), (3) validation of the established quantitative imaging setup using a 3D printed two-organ phantom (ICRP110-based kidney and spleen). In contrast to previous efforts, traceability of the activity measurement was required for each participant, and all participants were asked to calculate uncertainties for their SPECT-based activities. Results: Similar combinations of imaging system and reconstruction lead to similar image calibration factors. The activity ratio results of the anthropomorphic phantom validation demonstrate significant harmonization of quantitative imaging performance between the sites with all sites falling within one standard deviation of the mean values for all inserts. Activity recovery was underestimated for total kidney, spleen, and kidney cortex, while it was overestimated for the medulla. Conclusion: This international comparison exercise demonstrates that harmonization of quantitative SPECT/CT is feasible when following very specific instructions of a dedicated calibration protocol, as developed within the MRTDosimetry project. While quantitative imaging performance demonstrates significant harmonization, an over- and underestimation of the activity recovery highlights the limitations of any partial volume correction in the presence of spill-in and spill-out between two adjacent volumes of interests.