[Clinical features of immune checkpoint inhibitor-related myositis in patients with urological cancer]

OBJECTIVE

Immune checkpoint inhibitors (ICI) have significantly improved the treatment efficacy of a variety of malignant tumors. However, patients may experience a series of special side effects during treatments with ICI. Immune-related myositis after ICI treatment is characterized by autoimmune rheumatic and musculoskeletal damage, which is relatively rare. To analyze the clinical characteristics and outcomes of ICI-associated myositis in urological tumors, we summarized the clinical manifestations, electrophysiological and pathological characteristics, treatments and outcomes in 8 patients.

METHODS

The clinical data of the 8 patients with immune-related myositis after ICI treatment for urological tumors treated in the Department of Urology, Peking University First Hospital from March 2018 to March 2022 were retrospectively analyzed for demographic characteristics, drug regimen, clinical symptoms, laboratory indices, electromyography examination, pathological manifestations and outcomes.

RESULTS

The eight patients included 2 females and 6 males with a median age of 68 years, all treated with ICI for urological neoplasms, including 2 upper tract urothelial carcinoma (UTUC), 3 renal cell carcinoma (RCC), and 3 bladder cancer (BCa). The median time between the first ICI treatment and the detection of immune-related myositis was 39.5 days, and the median duration of treatment was 2 sessions. The main symptoms were muscle pain and weakness, 5 cases with ptosis, 3 cases with secondary rhabdomyolysis, 5 cases with myocarditis, 1 case with myasthenia gravis, and 1 case with enterocolitis. Among them, patients with immune-related myocarditis had a shorter interval from the first anti-programmed cell death protein-1 (PD-1) therapy to the onset of immune-related myositis (P=0.042) compared with patients without myocarditis. The 8 patients had significant elevation of transaminases and muscle enzyme profile indexes, and 5 patients showed positive auto-antibodies. 3 patients had perfected muscle biopsies and showed typical skeletal muscle inflammatory myopathy-like pathological changes with CD3⁺, CD4⁺, CD8⁺, CD20⁺ lymphocytes and CD68⁺ macrophage infiltration. After the diagnosis of immune-related myositis, all the 8 patients immediately discontinued ICI therapy and improved after intravenous administration of methylprednisolone alone or in combination with gamma-globulin.

CONCLUSION

Immune-related myositis after ICI treatment is an immune-related adverse reactions (irAEs) with unique clinical and pathological features, commonly combined with cardiovascular adverse reactions. Immediate discontinuation of ICI and initiation of glucocorticoid therapy may improve the patient's condition in a timely manner.

[Three dimensional nephrometry system for partial nephrectomy: Our initial exploration]

OBJECTIVE

To construct a preoperative evaluation system for partial nephrectomy using CT three-dimensional visualization technology and to explore its practical value.

METHODS

The clinical data of the patients who underwent partial nephrectomy for renal tumors in Department of Urology, Peking University First Hospital were collected retrospectively. At the same time, the homogenized standard data of patients who underwent partial nephrectomy for renal tumors were collected in 16 clinical centers in China. The CT three-dimensional visualization system was applied (IPS system, Yorktal) to evaluate tumor anatomy, blood supply, perirenal fat and other information. The parameters were summarized to build a three-dimensional nephrometry system, on the basis of which virtual surgery design and intraoperative navigation were completed.

RESULTS

A three-dimensional visualization image was established based on the enhanced CT urography. The nephrometry system included the longest diameter and volume of the tumor, proportion volume of tumor invading the parenchyma, maximum depth of the tumor invading the parenchyma, contact surface area, flatness of the tumor surface, renal segment where the tumor was located, vascular variation, and perirenal fat. The average two-dimensional diameter of the tumor was (2.78±1.43) cm, the average three-dimensional maximum diameter was (3.09±1.35) cm, and the average postoperative pathological size was (3.01±1.38) cm. The maximum tumor diameter in the three-dimensional image was significantly related to the prolonged renal artery clamping time and intra-operative blood loss (r=0.502, P=0.020; r=0.403, P=0.046). The three-dimensional and pathological tumor volume were (25.7±48.4) cm³ and (33.0±36.4) cm³, respectively (P=0.229). The tumor volume was significantly related to the intraoperative blood loss (r=0.660, P < 0.001). The proportion volume of the tumor invading into renal parenchyma was significantly related to the prolongation of renal artery clamping and the occurrence of postoperative complications (r=0.410, P=0.041; r=0.587, P=0.005). The tumor contact surface area and the presence of vascular variation did not show correlation with the perioperative data and postoperative complications. While the preoperative evaluation was completed, the reconstructed three-dimensional image could be zoomed, rotated, combined display, color adjustment, transparency, and simulated cutting on the Touch Viewer system. The process generally consisted of showing or hiding the tissue, adjusting the transparency of the interested area, rotating and zooming the image to match the position of the surgical patient. Together, these functions met the requirements of preoperative virtual surgery plan and intraoperative auxiliary navigation.

CONCLUSION

Three-dimensional images can provide a more intuitive anatomical structure. The CT three-dimensional visua-lization system clearly displays tumor anatomical parameters, blood supply and perirenal fat. The three-dimensional nephrometry system for renal tumors can help predict the difficulty of partial nephrectomy and perioperative complications. Importing the reconstructed three-dimensional visualization image into the specified program or robot operating system can complete virtual surgery and intraoperative navigation, helping the surgeon to better grasp the surgical process. The indexes included in the nephrometry system and the score weights of each index need to be confirmed and perfected by multi-center study with large samples.