Volume increase of spleen in melanoma patients undergoing immune checkpoint blockade

Changes in Posttreatment Spleen Volume Associated with Immunotherapy Outcomes for Advanced Hepatocellular Carcinoma

Purpose

We investigated whether spleen volume (SV) changes were associated with treatment outcomes in advanced hepatocellular carcinoma (HCC) patients who received immunotherapy or first-line sorafenib.

Patients and Methods

Patients with advanced HCC who underwent immunotherapy or first-line sorafenib at our institute were retrospectively analyzed. CT was used to measure SV before and within 3 months of treatment initiation. Tumor assessment followed Response Evaluation Criteria in Solid Tumors version 1.1. The association between SV change and tumor response or progression-free survival (PFS) was analyzed. The inverse probability of treatment weighting (IPTW) was used to adjust for differences in baseline characteristics.

Results

The immunotherapy group comprised 143 patients (124 men, mean age, 59.8 years ± 11.2 [standard deviation]), while the sorafenib group had 57 (47 men, mean age, 59.6 years ± 9.9). SV increased in 108 (75.5%) immunotherapy and 21 (36.8%) sorafenib patients. In the immunotherapy group, patients with increased SV were more likely than those with decreased SV to have a higher disease control rate (76.9% vs 57.1%, p = 0.024) and durable clinical benefit (52.8% vs 25.7%, p = 0.005). It was also associated with extended PFS in the immunotherapy group in both the univariate (p = 0.028) and multivariate (p = 0.014) analysis. By contrast, in the sorafenib group, an increased in SV was not associated with treatment response but was presumably associated with reduced PFS (p = 0.072) in the multivariate analysis. After IPTW adjustment, the increase in SV remained a significant predictor for DCB and PFS in the immunotherapy group.

Conclusion

Most patients exhibited an increase in SV after the initiation of immunotherapy, which may be used to predict response and prognosis. However, this association was not observed in patients who received sorafenib.

The role of spleen volume change in predicting immunotherapy response in metastatic renal cell carcinoma

INTRODUCTION

Resistance to immune checkpoint inhibitors (ICI) is a significant issue in metastatic renal cell carcinoma (mRCC), as it is in the majority of cancer types. An important deficiency in immunooncology today is the lack of a predictive factor to identify this patient group. Myeloid-derived suppressor cells (MDSC) are a type of cell that contributes to immunotherapy resistance by inhibiting T cell activity. While it accumulates in the tumor microenvironment and blood, it can also accumulate in lymphoid organs such as the spleen and cause splenomegaly. Therefore we aimed to evaluate the effect of increase in splenic volume, which can be considered as an indirect indicator of increased MDSC cells, on survival outcomes in mRCC patients.

METHODS

We analyzed 45 patients with mRCC who received nivolumab as a second-line or subsequent therapy. Splenic volume was analyzed from baseline imaging before starting nivolumab and from control imaging performed within the first 6 months of treatment initiation. Additionally, we analyzed how patients' body mass index (BMI), IMDC risk score, ECOG performance status, nephrectomy status, neutrophil-lymphocyte ratio (NLR), Platelet-to-lymphocyte ratio (PLR) and sites of metastasis.

RESULTS

Median splenic volume change was 10% (ranging from - 22% to + 117%) during follow-up. Change in splenic volume was found to be associated with overall survival (OS) and progression-free survival (PFS) (p = 0.025, 0.04). The median PFS in patients with increased splenic volume was 5 months, while it was 17 months in patients without increased splenic volume. (HR 2.1, 95% CI (1-4), p = 0.04). The median OS in patients with increased splenic volume was 9 months, while it was 35 months in patients without increased splenic volume (HR 2.7, 95% CI (1.1-6.2), p = 0.025). In four patients with decreased splenic volume, neither PFS nor OS could reach the median value. Log-rank p value in respectively (0.015, 0.035), The group in which an increase in volume was accompanied by a high NLR had the shortest survival rate. Basal splenic volume was analyzed separately. However, neither PFS nor OS differed significantly.

CONCLUSION

Our findings suggest that the change in splenic volume throughout immunotherapy regimens may be utilized to predict PFS and OS in mRCC patients undergoing treatment.

Change in Splenic Volume as a Surrogate Marker for Immunotherapy Response in Patients with Advanced Urothelial and Renal Cell Carcinoma-Evaluation of a Novel Approach of Fully Automated Artificial Intelligence Based Splenic Segmentation

BACKGROUND

In the treatment of advanced urothelial (aUC) and renal cell carcinoma (aRCC), biomarkers such as PD-1 and PD-L1 are not robust prognostic markers for immunotherapy (IO) response. Previously, a significant association between IO and a change in splenic volume (SV) was described for several tumour entities. To the best of our knowledge, this study presents the first correlation of SV to IO in aUC and aRCC.

METHODS

All patients with aUC (05/2017-10/2021) and aRCC (01/2012-05/2022) treated with IO at our academic centre were included. SV was measured at baseline, 3 and 9 months after initiation of IO using an in-house developed convolutional neural network-based spleen segmentation method. Uni- and multivariate Cox regression models for overall survival (OS) and progression-free survival (PFS) were used.

RESULTS

In total, 35 patients with aUC and 30 patients with aRCC were included in the analysis. Lower SV at the three-month follow-up was significantly associated with improved OS in the aRCC group.

CONCLUSIONS

We describe a new, innovative artificial intelligence-based approach of a radiological surrogate marker for IO response in aUC and aRCC which presents a promising new predictive imaging marker. The data presented implicate improved OS with lower follow-up SV in patients with aRCC.

Imaging-calculated splenic volume is associated with response in melanoma patients treated with immunotherapy

Background: Predicting the roughly 50% of melanoma patients that will respond to immunotherapy is challenging. We tested if splenic volume could be a predictive biomarker. Methods: Splenic volume was measured by a semiautomated commercial software tool in pre- and post-treatment PET/CT, CT or MRI in 50 melanoma patients treated with immune checkpoint inhibitors. Results: Subjects with smaller spleens had better progression-free survival (median not achieved after 30.6 months of follow-up vs median 11.2 months; p = 0.0213) than their counterparts. A cut-off of <244 cm³ yielded a sensitivity of 83% and specificity of 54% to identify responders. Conclusion: Measuring splenic volume on imaging scans is feasible. Smaller pretreatment spleen volume is associated with better responses to immune checkpoint inhibitors.

Baseline Splenic Volume Outweighs Immuno-Modulated Size Changes with Regard to Survival Outcome in Patients with Hepatocellular Carcinoma under Immunotherapy

Simple Summary

Splenic volume (SV) has been identified as a highly predictive parameter for prognosis in patients with hepatocellular carcinoma (HCC). Moreover, an association between immunotherapy and an increase in SV has been described for various types of cancer. In our cohort of patients with HCC under immunotherapy, SV was a highly predictive factor for overall survival at baseline and initial follow-up. Although a large proportion of patients (76%) showed an SV increase after the initiation of immunotherapy, this additional immuno-modulated SV change was negligible compared to long-standing changes in the splanchnic circulation in our patient cohort.

Abstract

Background: An association between immunotherapy and an increase in splenic volume (SV) has been described for various types of cancer. SV is also highly predictive of overall survival (OS) in patients with hepatocellular carcinoma (HCC). We evaluated SV and its changes with regard to their prognostic influence in patients with HCC undergoing immunotherapy. Methods: All patients with HCC who received immunotherapy in first or subsequent lines at our tertiary care center between 2016 and 2021 were screened for eligibility. SV was assessed at baseline and follow-up using an AI-based tool for spleen segmentation. Patients were dichotomized into high and low SV based on the median value. Results: Fifty patients were included in the analysis. The median SV prior to treatment was 532 mL. The median OS of patients with high and low SV was 5.1 months and 18.1 months, respectively (p = 0.01). An increase in SV between treatment initiation and the first follow-up was observed in 28/37 (75.7%) patients with follow-up imaging available. This increase in itself was not prognostic for median OS (7.0 vs. 8.5 months, p = 0.73). However, patients with high absolute SV at the first follow-up continued to have impaired survival (4.0 months vs. 30.7 months, p = 0.004). Conclusion: High SV prior to and during treatment was a significant prognostic factor for impaired outcome. Although a large proportion of patients showed an SV increase after the initiation of immunotherapy, this additional immuno-modulated SV change was negligible compared to long-standing changes in the splanchnic circulation in patients with HCC.

Splenic volume as a predictor of treatment response in patients with non-small cell lung cancer receiving immunotherapy

Introduction

The spleen is a lymphoid organ and we hypothesize that clinical benefit to immunotherapy may present with an increase in splenic volume during treatment. The purpose of this study was to investigate whether changes in splenic volume could be observed in those showing clinical benefit versus those not showing clinical benefit to pembrolizumab treatment in non-small cell lung cancer (NSCLC) patients.

Materials and methods

In this study, 70 patients with locally advanced or metastatic NSCLC treated with pembrolizumab; and who underwent baseline CT scan within 2 weeks before treatment and follow-up CT within 3 months after commencing immunotherapy were retrospectively evaluated. The splenic volume on each CT was segmented manually by outlining the splenic contour on every image and the total volume summated. We compared the splenic volume in those achieving a clinical benefit and those not achieving clinical benefit, using non-parametric Wilcoxon signed-rank test. Clinical benefit was defined as stable disease or partial response lasting for greater than 24 weeks. A p-value of <0.05 was considered statistically significant.

Results

There were 23 responders and 47 non-responders based on iRECIST criteria and 35 patients with clinical benefit and 35 without clinical benefit. There was no significant difference in the median pre-treatment volume (175 vs 187 cm3, p = 0.34), post-treatment volume (168 vs 167 cm3, p = 0.39) or change in splenic volume (-0.002 vs 0.0002 cm3, p = 0.97) between the two groups. No significant differences were also found between the splenic volume of patients with partial response, stable disease or progressive disease (p>0.017). Moreover, there was no statistically significant difference between progression-free survival and time to disease progression when the splenic volume was categorized as smaller or larger than the median pre-treatment or post-treatment volume (p>0.05).

Conclusion

No significant differences were observed in the splenic volume of those showing clinical benefit versus those without clinical benefit to pembrolizumab treatment in NSCLC patients. CT splenic volume cannot be used as a potentially simple biomarker of response to immunotherapy.