Real-time ex vivo perfusion of human lymph nodes invaded by cancer (REPLICANT): a feasibility study

Understanding how breast cancer (BC) grows in axillary lymph nodes (ALNs), and refining how therapies might halt that process, is clinically important. However, modelling the complex ALN microenvironment is difficult, and no human models exist at present. We harvested ALNs from ten BC patients, and perfused them at 37 °C ex vivo for up to 24 h. Controlled autologous testing showed that ALNs remain viable after 24 h of ex vivo perfusion: haematoxylin and eosin-stained histological appearance and proliferation (by Ki67 immunohistochemistry) did not change significantly over time for any perfused ALN compared with a control from time-point zero. Furthermore, targeted gene expression analysis (NanoString PanCancer IO360 panel) showed that only 21/750 genes were differentially expressed between control and perfused ALNs (|log₂ FC| > 1 and q < 0.1): none were involved in apoptosis and metabolism, but rather all 21 genes were involved in immune function and angiogenesis. During perfusion, tissue acid-base balance remained stable. Interestingly, the flow rate increased (p < 0.001) in cancer-replaced (i.e. metastasis occupied more than 90% of the surface area on multiple levels) compared to cancer-free nodes (i.e. nodes with no metastasis on multiple sections). CXCL11 transcripts were significantly more abundant in cancer-replaced nodes, while CXCL12 transcripts were significantly more abundant in cancer-free nodes. These cytokines were also detected in the circulating perfusate. Monoclonal antibodies (nivolumab and trastuzumab) were administered into a further three ALNs to confirm perfusion efficacy. These drugs saturated the nodes; nivolumab even induced cancer cell death. Normothermic ALN perfusion is not only feasible but sustains the tumour microenvironment ex vivo for scientific investigation. This model could facilitate the identification of actionable immuno-oncology targets. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

68Ga-Sienna+ for PET-MRI Guided Sentinel Lymph Node Biopsy: Synthesis and Preclinical Evaluation in a Metastatic Breast Cancer Model

Sentinel lymph node biopsy (SLNB) is commonly performed in cancers that metastasise via the lymphatic system. It involves excision and histology of sentinel lymph nodes (SLNs) and presents two main challenges: (i) sensitive whole-body localisation of SLNs, and (ii) lack of pre-operative knowledge of their metastatic status, resulting in a high number (>70%) of healthy SLN excisions. To improve SLNB, whole-body imaging could improve detection and potentially prevent unnecessary surgery by identifying healthy and metastatic SLNs. In this context, radiolabelled SPIOs and PET-MRI could find applications to locate SLNs with high sensitivity at the whole-body level (using PET) and guide high-resolution MRI to evaluate their metastatic status. Here we evaluate this approach by synthesising a GMP-compatible 68Ga-SPIO (68Ga-Sienna+) followed by PET-MR imaging and histology studies in a metastatic breast cancer mouse model. Methods. A clinically approved SPIO for SLN localisation (Sienna+) was radiolabelled with 68Ga without a chelator. Radiochemical stability was tested in human serum. In vitro cell uptake was compared between 3E.Δ.NT breast cancer cells, expressing the hNIS reporter gene, and macrophage cell lines (J774A.1; RAW264.7.GFP). NSG-mice were inoculated with 3E.Δ.NT cells. Left axillary SLN metastasis was monitored by hNIS/SPECT-CT and compared to the healthy right axillary SLN. 68Ga-Sienna+ was injected into front paws and followed by PET-MRI. Imaging results were confirmed by histology. Results.68Ga-Sienna+ was produced in high radiochemical purity (>93%) without the need for purification and was stable in vitro. In vitro uptake of 68Ga-Sienna+ in macrophage cells (J774A.1) was significantly higher (12 ± 1%) than in cancer cells (2.0 ± 0.1%; P < 0.001). SPECT-CT confirmed metastasis in the left axillary SLNs of tumour mice. In PET, significantly higher 68Ga-Sienna+ uptake was measured in healthy axillary SLNs (2.2 ± 0.9 %ID/mL), than in metastatic SLNs (1.1 ± 0.2 %ID/mL; P = 0.006). In MRI, 68Ga-Sienna+ uptake in healthy SLNs was observed by decreased MR signal in T2/T2*-weighted sequences, whereas fully metastatic SLNs appeared unchanged. Conclusion.68Ga-Sienna+ in combination with PET-MRI can locate and distinguish healthy from metastatic SLNs and could be a useful preoperative imaging tool to guide SLN biopsy and prevent unnecessary excisions.

A randomized phase II study of nivolumab monotherapy versus nivolumab combined with ipilimumab in advanced gastrointestinal stromal tumor (GIST)

11017

Background: Most GISTs are driven by mutations in KIT and PDGFRa and secondary mutations are felt to confer resistance to TKIs. In advanced/metastatic GIST, the benefit of second line TKIs and beyond is progressively less after imatinib failure. As such, novel non-TKI approaches are important to explore. Here we report interim analyses of safety and efficacy in advanced GIST patients treated with immunotherapy. Methods: Patients with advanced/metastatic GIST refractory to at least imatinib were enrolled on a randomized, parallel group, unblinded Phase 2 trial of either nivo (240 mg Q2wks) or nivo (240 mg Q2wks) with ipi (1mg/kg Q6wks) for up to 2 years. The primary endpoint was the objective response rate(ORR) of nivo alone or nivo + ipi by RECIST 1.1 criteria. Imaging was assessed by investigator and 3 independent radiologists. Patients were randomized 1:1 and were restaged every 8 weeks. With a sample size of 20 per group, an exact binomial test with a nominal 0.050 one-sided significance level will have 82% power to detect the difference between the null hypothesis response rate 1.5% and the alternative response rate of 15%. Secondary objectives are to ascertain the PFS, CBR, RR by Choi criteria and safety. Blood and biopsies are also being collected. Results: At cutoff, 29 patients (27 evaluable) with a median of 3 (1-7) lines of prior therapies have started on trial. In the nivo only arm, 7/15 pts had a best response of SD for a CBR of 46.7% with the median PFS being 8.57 wks. In the nivo + ipi arm, 1/12 patients had a PR and 2/12 have SD for a CBR of 25.0% (95% exact C.I. 5.5%-57.2%) with a median PFS of 9.1 wks. 8 patients have been on therapy for more than 6 months and two patients with a KIT Exon 17 mutation had radiographic disease shrinkage. Most AEs were grades 1-2 with fatigue (37%) being the most common. 4 Grade 3/4 AEs occurred in the nivo and ipi arm (hyperglycemia, weakness, diarrhea x 2) and 4 grade 3/4AEs occurred in the nivo arm (DKA, hyperglycemia, rash, fatigue). Pretreatment biopsies have been obtained in all patients and blood has been collected on all patients for correlative analysis. Conclusions: In a heavily pretreated GIST population, responses and disease control with both nivo and nivo + ipi were observed. To date, the drugs have been well tolerated and no new safety signals have been observed in this disease state. Clinical trial information: NCT02880020.

Radiomic correlates of molecular and clinicopathological characteristics in clear cell renal cell carcinoma

625

Background: Clear cell renal cell carcinoma (ccRCC) is a highly vascularized tumor and has a heterogeneous molecular profile, but the correlation between its tumor biology and radiomic features have only recently been investigated. As 70% of ccRCCs are detected incidentally at imaging, and tumor phenotypes are only available after surgery, a non-invasive biomarker to predict ccRCC phenotypes and aggressiveness on imaging may be clinically valuable, as low grade lesions may undergo active surveillance. Methods: With IRB approval and HIPAA compliance, our study cohort comprised 92 consecutive patients with 102 ccRCCs (mean age, 62 years (SD ± 14.2) with histopathology and molecular endpoints imaged preoperatively on CT with a four-phase renal protocol [unenhanced (U), corticomedullary (C), nephrographic (N), excretory (E)]. Radiomic data was obtained by contouring the entire ccRCC in each phase to obtain a 3D tumor volume of interest (VOI). The mean enhancement in each phase the and wash-in and wash-out of enhancement was calculated for each ccRCC. Molecular data was obtained through immunohistochemistry of resected ccRCCs to assess carbonic anhydrase-IX (CAIX), microvessel density (MVD), phosphatase and tension homolog (PTEN), and tumor grade (TG). Categorical variables were analyzed with logistic regression and odds ratio (OR) was reported. Continuous variables were analyzed with linear regression and Pearson correlation coefficient (r2) was reported. P-values < .05 were considered significant. Results: Significant radiomic associations included TG and 3D tumor enhancement in the C (OR = 4.72, p = .030), N (OR = 17.71, p < .0001), and E phases (OR = 17.10, p < .0001), and wash-in from U to C (OR = 8.27, p = .004). MVD had a significant positive association with 3D tumor enhancement in the C phase (r2= 0.410, p < .0001), wash-in from U to C (r2= 0.435, p < .0001) and wash-out from the C to N (r2= 0.435, p = .001). There were no significant radiomic correlates with CAIX or PTEN expression. Conclusions: A 3D ccRCC VOI on multiphasic CT had significant correlations with TG and MVD, independent of clinical features, potentially becoming a predictive imaging biomarker of ccRCC aggressiveness and clinical outcome.

Is axillary ultrasound imaging necessary for all patients with breast cancer?

Better use selectively

Combined use of fluorescence with a magnetic tracer and dilution effect upon sentinel node localization in a murine model

Background

Sentinel node biopsy using radioisotope and blue dye remains a gold standard for axillary staging in breast cancer patients with low axillary burden. However, limitations in the use of radioisotopes have resulted in emergence of novel techniques. This is the first in vivo study to assess the feasibility of combining the two most common novel techniques of using a magnetic tracer and indocyanine green (ICG) fluorescence.

Materials and methods

A total of 48 mice were divided into eight groups. Groups 1 and 2, the co-localization groups, received an injection of magnetic tracers (Resovist^® and Sienna+^®, respectively) and ICG fluorescence; distilled water was used as the solvent of ICG. Groups 3 and 4, the diluted injection groups, received an injection of magnetic tracers (Resovist and Sienna+, respectively) and saline for dilution. Groups 5, 6, and 7, the control groups, received magnetic tracer (Resovist, Sienna+) and ICG alone, respectively. Fluorescent intensity assessment and iron quantification of excised popliteal lymph nodes were performed. Group 1', a co-localization group, received an injection of magnetic tracers (Resovist) and ICG' fluorescence: saline was used as the solvent for ICG.

Results

Lymphatic uptake of all tracers was confined to the popliteal nodes only, with co-localization confirmed in all cases and no significant difference in fluorescent intensity or iron content of ex vivo nodes between the groups (except for Group 1'). There was no impact of dilution on the iron content in the diluted Sienna+ group, but it significantly enhanced Resovist uptake (P=0.005). In addition, there was a significant difference in iron content (P=0.003) in Group 1'.

Conclusion

The combination of a magnetic tracer (Resovist or Sienna+) and ICG fluorescence is feasible for sentinel node biopsy and will potentially allow for precise transcutaneous node identification, in addition to accurate intraoperative assessment. This radioisotope-free "combined technique" warrants further assessment within a clinical trial.

Novel techniques for intraoperative assessment of margin involvement

Breast conserving surgery (BCS) is now the standard of care for the majority of women with early stage breast cancer. There is a finite rate of ipsilateral breast tumour recurrence (IBTR) for breast conserving therapy (BCT) with annual rates of less than 1% for specialist breast practices. There has been recent consensus on the definition of an adequate resection margin for both invasive and noninvasive breast cancer treated with BCS, although some variation in margin policy persists with definitions of 'no tumour at ink', 1 and 2 mm margin mandates. Despite the development of methods for intraoperative assessment of margins, up to 20% of patients require further surgery (cavity re-excision or completion mastectomy) to achieve clear surgical margins. In the past decade, several novel technologies for intraoperative margin assessment have been explored with the aim of reducing rates of re-operation and its attendant patient anxiety, inconvenience and additional cost. Ongoing studies are addressing the safety, feasibility and cost-effectiveness of these novel technologies relative to methods in routine clinical usage.

Update on intraoperative radiotherapy: new challenges and issues

Intraoperative radiotherapy (IORT) for breast cancer has challenged the standard external beam radiotherapy (EBRT) and has been shown to be non-inferior for treating early breast cancer in the past decade. Several technologies have been tested for IORT and various randomised controlled trials are still ongoing. Different methods of application of IORT have also been evaluated, from early breast cancer to tumour bed boost radiotherapy amongst high risk women. TARGIT-A and ELIOT trials have reported a low incidence of local recurrence and good survival in both arms. Moreover, mortality has been found to be lower amongst women who underwent partial breast radiotherapy compared to those treated with EBRT in a recent meta-analysis. Despite this, IORT has not been introduced in the current clinical practice as yet, and many clinicians do not mention this treatment option to patients awaiting breast cancer surgery. The scientific community does not unanimously support the effectiveness of IORT and still raises concerns about introducing IORT as a standard treatment option for breast cancer. Current evidence demonstrates that IORT is ready for roll-out; it is time to let well-selected and informed patients be offered this treatment option in the current clinical practice.

International validation of the European Organisation for Research and Treatment of Cancer QLQ-BRECON23 quality-of-life questionnaire for women undergoing breast reconstruction

Background

The aim was to carry out phase 4 international field-testing of the European Organisation for Research and Treatment of Cancer (EORTC) breast reconstruction (BRECON) module. The primary objective was finalization of its scale structure. Secondary objectives were evaluation of its reliability, validity, responsiveness, acceptability and interpretability in patients with breast cancer undergoing mastectomy and reconstruction.

Methods

The EORTC module development guidelines were followed. Patients were recruited from 28 centres in seven countries. A prospective cohort completed the QLQ-BRECON15 before mastectomy and the QLQ-BRECON24 at 4–8 months after reconstruction. The cross-sectional cohort completed the QLQ-BRECON24 at 1–5 years after reconstruction, and repeated this 2–8 weeks later (test–retest reliability). All participants completed debriefing questionnaires.

Results

A total of 438 patients were recruited, 234 in the prospective cohort and 204 in the cross-sectional cohort. A total of 414 reconstructions were immediate, with a comparable number of implants (176) and donor-site flaps (166). Control groups comprised patients who underwent two-stage implant procedures (72, 75 per cent) or delayed reconstruction (24, 25 per cent). Psychometric scale validity was supported by moderate to high item-own scale and item-total correlations (over 0·5). Questionnaire validity was confirmed by good scale-to-sample targeting, and computable scale scores exceeding 50 per cent, except nipple cosmesis (over 40 per cent). In known-group comparisons, QLQ-BRECON24 scales and items differentiated between patient groups defined by clinical criteria, such as type and timing of reconstruction, postmastectomy radiotherapy and surgical complications, with moderate effect sizes. Prospectively, sexuality and surgical side-effects scales showed significant responsiveness over time (P &lt; 0·001). Scale reliability was supported by high Cronbach's α coefficients (over 0·7) and test–retest (intraclass correlation more than 0·8). One item (finding a well fitting bra) was excluded based on high floor/ceiling effects, poor test–retest and weak correlations in factor analysis (below 0·3), thus generating the QLQ-BRECON23 questionnaire.

Conclusion

The QLQ-BRECON23 is an internationally validated tool to be used alongside the EORTC QLQ-C30 (cancer) and QLQ-BR23 (breast cancer) questionnaires for evaluating quality of life and satisfaction after breast reconstruction.

High-intensity focused ultrasound in the treatment of breast fibroadenomata (HIFU-F trial)

BACKGROUND

High-intensity focussed ultrasound (HIFU) is a non-invasive ablative technique utilising the application of high frequency ultrasound (US) pressure waves to cause tissue necrosis. This emerging technology is currently limited by prolonged treatment times. The aim of the HIFU-F trial was to perform circumferential HIFU treatment as a means of shortening treatment times.

METHODS

A prospective trial was set up to treat 50 consecutive patients ≥18 years of age. Eligible patients possessed symptomatic fibroadenomata, visible on US. Patients ≥25 years of age required histological confirmation of the diagnosis. Primary outcome measures were reduction in treatment time, reduction in volume on US after 12 months and complication rates.

RESULTS

HIFU treatment was performed in 51 patients (53 treatments) with a mean age of 29.8 years (SD 7.2 years) and a diameter of 2.6 cm (SD 1.4 cm). Circumferential ablation reduced treatment times by an estimated 19.9 min (SD 25.1 min), which is a 29.4% (SD 15.2%) reduction compared with whole lesion ablation. Volume reduction of 43.2% (SD 35.4%; p < 0.005, paired t-test) was observed on US at 12 months post-treatment. Local complications completely resolved at 1 month apart from skin hyper-pigmentation, which persisted in nine cases at three months, six cases at 6 months and six at 12 months.

CONCLUSION

Circumferential HIFU treatment for breast fibroadenomata is feasible to reduce both lesion size and treatment time. HIFU is a non-invasive alternative technique for the treatment of breast fibroadenomata. ISRCTN registration: 76622747.

Ablative techniques for the treatment of benign and malignant breast tumours

Minimally invasive techniques like high intensity focused ultrasound, radiofrequency ablation, cryo-ablation, laser ablation and microwave ablation have been used to treat both breast fibroadenomata and breast cancer as an alternative to surgical excision, potentially reducing the complications, improving cosmesis and reducing hospital stay. This review describes the most common minimally invasive techniques available, their history and some of the studies performed with these techniques in both benign and malignant lesions. In addition we described some of the difficulties of using these minimally invasive techniques such as optimization of anaesthesia, imaging and immobilisation in order to increase the complete histopathological ablation rates.

Type 1 papillary renal cell carcinoma: differentiation from Type 2 papillary RCC on multiphasic MDCT

PURPOSE

To investigate whether multiphasic MDCT enhancement can help differentiate type 1 papillary renal cell carcinoma (RCC) from type 2 papillary RCC.

METHODS

With IRB approval for this HIPAA-compliant retrospective study, we derived a cohort of 36 type 1 papillary RCCs and 33 type 2 papillary RCCs with preoperative multiphasic MDCT with up to four phases (unenhanced, corticomedullary, nephrographic, and excretory) from 2000 to 2013. Following segmentation, a computer-assisted detection (CAD) algorithm selected a 0.5 cm-diameter region of maximal attenuation within each lesion in each phase; a 0.5 cm-diameter region of interest was manually placed on uninvolved renal cortex in each phase. The relative attenuation of each lesion was calculated as [(Lesion attenuation-cortex attenuation)/cortex attenuation] × 100. Absolute and relative attenuation values were compared using Mann-Whitney tests with Bonferroni correction for multiple comparisons.

RESULTS

Relative excretory phase attenuation of type 2 papillary RCCs was significantly greater than that of type 1 papillary RCCs (2.0 vs. -18.3, p = 0.005). Relative excretory phase attenuation differentiated type 1 papillary RCCs from type 2 papillary RCCs with an accuracy of 73% (36/49), sensitivity of 87% (26/30), positive predictive value of 74% (26/35), and negative predictive value of 71% (10/14).

CONCLUSION

Multiphasic MDCT enhancement may assist in differentiating type 1 papillary RCCs from type 2 papillary RCCs, if prospectively validated.

Is there a role for sentinel node biopsy in the pre-operative ultrasound positive axilla?

Axillary management in breast cancer is becoming increasingly conservative. This approach is based on the identification of low axillary burden on sentinel node biopsy (SNB). The modern practice of routine pre-operative axillary ultrasound has meant that patients are 'fast tracked' to axillary node clearance (ANC) in the presence of a histologically confirmed positive axilla. This practice reduces the number of patients undergoing SNB compared to the original trials, which evaluated the role of SNB, and those assessing safety of omission of ANC in low axillary burden. The risk of depriving patients with low axillary burden the opportunity to avoid ANC as a consequence of pre-operative ultrasound is discussed.

Intraoperative Assessment of Tumor Resection Margins in Breast-Conserving Surgery Using 18F-FDG Cerenkov Luminescence Imaging: A First-in-Human Feasibility Study

In early-stage breast cancer, the primary treatment option for most women is breast-conserving surgery (BCS). There is a clear need for more accurate techniques to assess resection margins intraoperatively, because on average 20% of patients require further surgery to achieve clear margins. Cerenkov luminescence imaging (CLI) combines optical and molecular imaging by detecting light emitted by 18F-FDG. Its high-resolution and small size imaging equipment make CLI a promising technology for intraoperative margin assessment. A first-in-human study was conducted to evaluate the feasibility of 18F-FDG CLI for intraoperative assessment of tumor margins in BCS. Methods: Twenty-two patients with invasive breast cancer received 18F-FDG (5 MBq/kg) 45-60 min before surgery. Sentinel lymph node biopsy was performed using an increased 99mTc-nanocolloid activity of 150 MBq to facilitate nodal detection against the γ-probe background signal (cross-talk) from 18F-FDG. The cross-talk and 99mTc dose required was evaluated in 2 lead-in studies. Immediately after excision, specimens were imaged intraoperatively in an investigational CLI system. The first 10 patients were used to optimize the imaging protocol; the remaining 12 patients were included in the analysis dataset. Cerenkov luminescence images from incised BCS specimens were analyzed postoperatively by 2 surgeons blinded to the histopathology results, and mean radiance and margin distance were measured. The agreement between margin distance on CLI and histopathology was assessed. Radiation doses to staff were measured. Results: Ten of the 12 patients had an elevated tumor radiance on CLI. Mean radiance and tumor-to-background ratio were 560 ± 160 photons/s/cm2/sr and 2.41 ± 0.54, respectively. All 15 assessable margins were clear on CLI and histopathology. The agreement in margin distance and interrater agreement was good (κ = 0.81 and 0.912, respectively). Sentinel lymph nodes were successfully detected in all patients. The radiation dose to staff was low; surgeons received a mean dose of 34 ± 15 μSv per procedure. Conclusion: Intraoperative 18F-FDG CLI is a promising, low-risk technique for intraoperative assessment of tumor margins in BCS. A randomized controlled trial will evaluate the impact of this technique on reexcision rates.

Correlation of tumor enhancement and imaging features on multiphasic multidetector CT with microvessel density as a step toward a minimally invasive method to predict Fuhrman nuclear grade in patients with clear cell renal cell carcinoma

e16049

Background: Clear cell renal cell carcinoma (ccRCC) is the most common tumor of the kidney. Up to 70% are incidentally detected on multiphasic CT. The prognosis for patients with ccRCC is related to Fuhrman grade (FG) and is diagnosed by biopsy or excision. There is a great need for a non-invasive method to assess tumor grade which may help inform clinical decision-making. The purpose of our study is to determine if contrast enhancement on CT predicts FG and microvessel density (MVD) of ccRCC lesions and to assess which combination of quantitative and qualitative radiological features and clinical features predict high FG ccRCC lesions. Methods: With IRB approval for this HIPAA-compliant retrospective study, our pathology and imaging databases were queried to obtain a cohort of ccRCC with a preoperative multiphasic (unenhanced (U), corticomedullary (C), nephrographic (N), and excretory (E)) CT scan. Tumors were stained with CD4 to quantify % MVD. Spearman’s rank correlation was calculated to test the strength of the association between CT enhancement, %MVD and FG. Stepwise logistic regression analysis was performed to determine the quantitative and/or qualitative feature with the highest performance in predicting high FG tumor. The multivariate logistic regression analysis was evaluated using ROC curves and AUCs. Results: Our cohort had 127 patients with 89 low-grade tumors and 43 high-grade tumors. The %wash-in of enhancement from the U to the C phase showed a significant correlation with %MVD of the tumor (R2= 0.181,p < . 001) as did enhancement of the tumor in the early C phase with %MVD (R2= 0.159,p < . 001). There was a significant inverse correlation with %MVD and FG (R2= 0.137,p < . 001). T-stage, tumor size, %MVD and presence of renal vein invasion were determined to be significant independent predictors of high grade lesions with an AUC of .838 (95% CI .748-.927). Conclusions: Lower grade ccRCC tumors have a higher MVD. Therefore, contrast material washes in at a faster rate from the UN to the CM phase, enabling low grade to be discriminated from high-grade tumors on CT.