Univariable and multivariable Mendelian randomization study identified the key role of gut microbiota in immunotherapeutic toxicity

BACKGROUND

In cancer patients receiving immune checkpoint inhibitors (ICIs), there is emerging evidence suggesting a correlation between gut microbiota and immune-related adverse events (irAEs). However, the exact roles of gut microbiota and the causal associations are yet to be clarified.

METHODS

To investigate this, we first conducted a univariable bi-directional two-sample Mendelian randomization (MR) analysis. Instrumental variables (IVs) for gut microbiota were retrieved from the MiBioGen consortium (18,340 participants). GWAS summary data for irAEs were gathered from an ICIs-treated cohort with 1,751 cancer patients. Various MR analysis methods, including inverse variance weighted (IVW), MR PRESSO, maximum likelihood (ML), weighted median, weighted mode, and cML-MA-BIC, were used. Furthermore, multivariable MR (MVMR) analysis was performed to account for possible influencing instrumental variables.

RESULTS

Our analysis identified fourteen gut bacterial taxa that were causally associated with irAEs. Notably, Lachnospiraceae was strongly associated with an increased risk of both high-grade and all-grade irAEs, even after accounting for the effect of BMI in the MVMR analysis. Akkermansia, Verrucomicrobiaceae, and Anaerostipes were found to exert protective roles in high-grade irAEs. However, Ruminiclostridium6, Coprococcus3, Collinsella, and Eubacterium (fissicatena group) were associated with a higher risk of developing high-grade irAEs. RuminococcaceaeUCG004, and DefluviitaleaceaeUCG011 were protective against all-grade irAEs, whereas Porphyromonadaceae, Roseburia, Eubacterium (brachy group), and Peptococcus were associated with an increased risk of all-grade irAEs.

CONCLUSIONS

Our analysis highlights a strong causal association between Lachnospiraceae and irAEs, along with some other gut microbial taxa. These findings provide potential modifiable targets for managing irAEs and warrant further investigation.

Posterior-scleritis: Case report of an uncommon immune-related adverse event in the treatment of advanced endometrial cancer

As Immune checkpoint inhibitors are being expanded for use in gynecologic malignancies, rare immune-related adverse events are more frequently being reported. Here we describe a 63-year-old with Stage IIIB mismatch repair deficient uterine adenocarcinoma who underwent six cycles of carboplatin and paclitaxel with partial response but persistent disease. She was then started on single agent pembrolizumab. After six cycles of pembrolizumab, she developed bilateral vision changes and was diagnosed with posterior scleritis. Pembrolizumab was held and she was treated with oral prednisone, with rapid resolution of symptoms. One month after completion of prednisone, vision changes were again reported and she was restarted on a longer oral prednisone course. She then underwent definitive surgical management consisting of a total laparoscopic hysterectomy and bilateral salpingo-oophorectomy, with final pathology of benign endometrial hyperplasia. She has completed her steroid course without any symptoms. Given her complete pathologic response, she was subsequently placed into surveillance and is currently without evidence of disease. Prompt recognition and treatment of this rare immune-related adverse event led to the prevention of potential permanent, debilitating outcomes.

Cardiovascular Imaging in Cardio-Oncology: The Role of Echocardiography and Cardiac MRI in Modern Cardio-Oncology

Cardiovascular (CV) events are an increasingly common limitation of effective anticancer therapy. Over the last decade imaging has become essential to patients receiving contemporary cancer therapy. Herein we discuss the current state of CV imaging in cardio-oncology. We also provide a practical apparatus for the use of imaging in everyday cardiovascular care of oncology patients to improve outcomes for those at risk for cardiotoxicity, or with established cardiovascular disease. Finally, we consider future directions in the field given the wave of new anticancer therapies.

Immune-Related Adverse Events in the Setting of PD-1/L1 Inhibitor Combination Therapy

In 2018, a multi‐disciplinary workshop was held at the Massachusetts General Hospital to discuss challenges in defining, diagnosing, and treating immune‐related adverse events (irAE), including those that occur in patients administered PD‐1/L1 inhibitor combination therapy. In this commentary, the workshop participants present a clinical case that illustrates the complexity of irAE diagnosis and management in a patient receiving PD‐1/L1 combination therapy, summarize the current state of PD‐1/L1 combination therapy, and discuss challenges and opportunities for the evaluation of irAEs as these combinations become more widely used to treat patients with cancer.