Survival Impact of Glucocorticoid Administration for Adverse Events During Immune Checkpoint Inhibitor Combination Therapy in Patients with Previously Untreated Advanced Renal Cell Carcinoma.

BACKGROUND: The impact of glucocorticoid administration for adverse events (AEs), including immune-related AEs, on the effectiveness of immune checkpoint inhibitor (ICI) combination therapy for advanced renal cell carcinoma (RCC) remains unknown. OBJECTIVES: To clarify the prognostic impact of glucocorticoid use for AEs during first-line ICI combination therapy for advanced RCC. PATIENTS AND METHODS: We retrospectively evaluated data from 194 patients who received dual ICI combination therapy [i.e., immunotherapy (IO)-IO] or combinations of ICIs with tyrosine kinase inhibitors (TKIs) as first-line therapy. The patients were divided into two groups according to the history of glucocorticoid administration in each treatment group. Survival based on glucocorticoid administration was assessed. RESULTS: A total of 101 (52.0%) and 93 (48.0%) patients received IO-IO and IO-TKI combination therapy, respectively. Glucocorticoids were administered to 46 (46%) and 22 (24%) patients in the IO-IO and IO-TKI groups, respectively. In the IO-IO group, progression-free survival (PFS) and overall survival (OS) were significantly longer in patients with glucocorticoid administration than in those without administration (median PFS: 14.4 versus 3.45 months, p = 0.0005; median OS: 77.6 versus 33.9 months, p = 0.0025). Multivariable analysis showed that glucocorticoid administration was an independent predictor of longer PFS (hazard ratio: 0.43, p = 0.0005) and OS (hazard ratio: 0.35, p = 0.0067) after adjustment for covariates. In the IO-TKI group, neither PFS nor OS significantly differed between patients treated with and without glucocorticoid administration (PFS: p = 0.0872, OS: p = 0.216). CONCLUSIONS: Glucocorticoid administration did not negatively impact the effectiveness of ICI combination therapy for RCC, prompting glucocorticoid treatment use when AEs develop.

First-line dual immune checkpoint inhibitor therapies versus combination therapies comprising immune checkpoint inhibitors and tyrosine kinase inhibitors for advanced renal cell carcinoma: a comparative analysis of the effectiveness using real-world data.

BACKGROUND: There are few comparative studies on dual immune checkpoint inhibitors (ICIs) (i.e., IO-IO) and combination therapies comprising ICIs plus tyrosine kinase inhibitors (TKIs) (i.e., IO-TKI) for advanced renal cell carcinoma (RCC), especially in real-world settings. METHODS: We retrospectively evaluated data of 175 patients with IMDC intermediate-risk or poor-risk RCC; as first-line therapy, 103 received IO-IO, and 72 received IO-TKI. An inverse probability of treatment weighting (IPTW) analysis was conducted to balance patients' backgrounds in the IO-IO and IO-TKI groups. RESULTS: Based on the IPTW analysis, progression-free survival (PFS) was longer in the IO-TKI group than in the IO-IO group (median: 15.6 vs. 8.3 months; p = 0.0386). In contrast, overall survival was not different between groups (median: 46.7 vs. 49.0 months; p = 0.465). Although the IPTW-adjusted objective response rate was not significantly different (51.2% vs. 43.9%; p = 0.359), the progressive disease rate as the best overall response was lower in the IO-TKI group than in the IO-IO group (3.3% vs. 27.4%; p < 0.0001). Regarding the safety profile, the treatment interruption rate was higher in the IO-TKI group than in the IO-IO group (70.3% vs. 49.2%; p = 0.005). In contrast, the IO-IO group had a higher corticosteroid administration rate (43.3% vs. 20.3%; p = 0.001). CONCLUSION: IO-TKI therapy exhibited superior effectiveness over IO-IO therapy in terms of PFS improvement and immediate disease progression prevention and was associated with a higher risk of treatment interruption and a lower risk of needing corticosteroids.

Relationship between clinical parameters and malformations in dogs diagnosed with atlanto-axial instability.

Atlanto-axial instability is a common disease that affects toy-breed dogs. Most cases of atlanto-axial instability are congenital. Furthermore, patients with atlanto-axial instability are predisposed to other concurrent diseases. Therefore, this study aimed to retrospectively determine the presence of concurrent diseases in cases with atlanto-axial instability using imaging data and analyze the relationship between clinical parameters and the incidence of complex malformations. The clinical data and imaging findings of 41 toy-breed dogs diagnosed with atlanto-axial instability were analyzed using their medical records and imaging data. Occipital dysplasia (17/27), atlanto-occipital overlapping (22/34), dens dysplasia (27/41), Chiari-like malformation (8/34), syringomyelia (5/34), lateral ventricular enlargement (20/36), and intracranial arachnoid cyst (5/35) were observed in patients with atlanto-axial instability. The body weight of the patients in the groups with atlanto-occipital overlapping and lateral ventricular enlargement was lower than that of those in the groups without these diseases (1.78 ± 0.71 vs 2.71 ± 1.15 kg, P = 0.0269, 1.60 ± 0.40 vs 2.75 ± 1.08 kg, P = 0.001, respectively). Furthermore, when the correlation between the total number of concurrent diseases and the age at onset and body weight was examined, it became clear that lower body weight was associated with the incidence of a greater number of concurrent diseases. Thus, the findings of this study suggest that toy-breed dogs are more likely to present with complex malformations and should be evaluated carefully with additional examinations and treatment methods.

Proof-of-concept study of the caninized anti-canine programmed death 1 antibody in dogs with advanced non-oral malignant melanoma solid tumors.

BACKGROUND: The anti-programmed death 1 (PD-1) antibody has led to durable clinical responses in a wide variety of human tumors. We have previously developed the caninized anti-canine PD-1 antibody (ca-4F12-E6) and evaluated its therapeutic properties in dogs with advance-staged oral malignant melanoma (OMM), however, their therapeutic effects on other types of canine tumors remain unclear. OBJECTIVE: The present clinical study was carried out to evaluate the safety profile and clinical efficacy of ca-4F12-E6 in dogs with advanced solid tumors except for OMM. METHODS: Thirty-eight dogs with non-OMM solid tumors were enrolled prospectively and treated with ca-4F12-E6 at 3 mg/kg every 2 weeks of each 10-week treatment cycle. Adverse events (AEs) and treatment efficacy were graded based on the criteria established by the Veterinary Cooperative Oncology Group. RESULTS: One dog was withdrawn, and thirty-seven dogs were evaluated for the safety and efficacy of ca-4F12-E6. Treatment-related AEs of any grade occurred in 13 out of 37 cases (35.1%). Two dogs with sterile nodular panniculitis and one with myasthenia gravis and hypothyroidism were suspected of immune-related AEs. In 30 out of 37 dogs that had target tumor lesions, the overall response and clinical benefit rates were 6.9% and 27.6%, respectively. The median progression-free survival and overall survival time were 70 days and 215 days, respectively. CONCLUSIONS: The present study demonstrated that ca-4F12-E6 was well-tolerated in non-OMM dogs, with a small number of cases showing objective responses. This provides evidence supporting large-scale clinical trials of anti-PD-1 antibody therapy in dogs.

Association Between Kidney Function and Outcomes Following Immune Checkpoint Inhibitor-Based Combination Therapy in Patients With Advanced Renal Cell Carcinoma.

BACKGROUND: It remains unclear whether kidney function affects outcomes following immune checkpoint inhibitor (ICI)-based combination therapy for advanced renal cell carcinoma (RCC). METHODS: We retrospectively evaluated data of 167 patients with advanced RCC, including 98 who received ICI dual combination therapy (ie, immunotherapy [IO]-IO) and 69 who received ICI combined with tyrosine kinase inhibitor (TKI) (ie, IO-TKI). In each regimen, treatment profiles were assessed according to the grade of chronic kidney disease (CKD) as defined by the KDIGO 2012 criteria. RESULTS: Of the 98 patients who received IO-IO, 31 (32%), 30 (31%), 15 (15%), and 22 (22%) had CKD G1/2, G3a, G3b, and G4/5, respectively. Of the 69 patients who received IO-TKI, 18 (26%), 25 (36%), and 26 (38%) had G1/2, G3a, and G3b/4/5, respectively. Regarding efficacy, progression-free survival, overall survival, or objective response rate was not different according to the CKD grade in both treatment groups (P > .05). Regarding safety, the rate of adverse events, treatment interruption, or corticosteroid administration was not different according to the CKD grade in the IO-IO group (P > .05), whereas in the IO-TKI group, the incidence of grade ≥ 3 adverse events were significantly higher (P = .0292), and the rates of ICI interruption (P = .0353) and corticosteroid administration (P = .0685) increased, according to the CKD grade. CONCLUSION: There is a differential safety but comparable efficacy profile between the IO-IO and IO-TKI regimens in patients with CKD. Further prospective studies are required to confirm these findings.

Osteosarcoma of the hyoid bone in a cat.

Case summary: A 10-year-old male neutered Abyssinian cat was presented with the chief complaint of a right pharyngeal mass. On palpation, the mass was easily palpable; it appeared well demarcated and mobile, and oval in shape. Radiographic examination showed a radiopaque pharyngeal mass, which was revealed to be a well-demarcated mass lesion with a radiopaque marginal area on CT examination. The inside of the mass was uniformly well enhanced on contrast CT examination. A three-dimensional image reconstructed from the CT images strongly suggested that the mass originated from the right stylohyoid bone. No abnormal lesions were observed in the thoracic and abdominal CT examinations. Surgical excision of the mass was scheduled 3 weeks after the first admission. The mass was bluntly separated from the surrounding musculature and resected together with the ipsilateral epihyoid bone adjacent to the mass. Histopathological examination of the resected mass showed neoplastic cells with osteoid formation, and the mass was histopathologically diagnosed as an osteosarcoma. The postoperative recovery from anaesthesia was uneventful, and the cat began feeding on its own from the third postoperative day. The 3-month postoperative CT evaluation revealed no local recurrence or distant metastasis. The cat showed no abnormal findings at the time of writing (6 months postoperatively). Relevance and novel information: Although osteosarcoma derived from the hyoid bone has rarely been reported in the veterinary field, this report suggests that such tumours may occur in cats. In addition, partial excision of the hyoid apparatus seems to be well tolerated in cats.

Sulfasalazine, a potent cystine-glutamate transporter inhibitor, enhances osteogenic differentiation of canine adipose-derived stem cells.

Cystine-glutamate transporter (xCT) is a plasma membrane transporter that imports cystine and indirectly contributes to the oxidative stress resistance associated with increased intracellular glutathione levels. Canine adipose-derived stem cells (CADSCs) include an xCT-positive subpopulation and show relatively low expression of osteogenic markers during in vitro osteogenic differentiation. Sulfasalazine (SSZ), a drug used to treat rheumatoid arthritis, suppresses xCT expression in cancer cells. In this study, we found that the SSZ treatment at 100 µM significantly suppressed xCT mRNA expression in CADSCs but did not significantly affect cell proliferation under the same conditions. Additionally, this treatment decreased the intracellular glutathione concentration. During in vitro osteogenic differentiation, the SSZ treatment at 50 µM and 100 µM significantly increased alizarin red staining and its quantification, as well as the concentration-dependent osteogenic differentiation markers (BMP1 and SPP) mRNA expression. Our results suggested that SSZ enhances the osteogenic differentiation potential of CADSCs and can potentially exhibit a superior therapeutic profile in canine bone regenerative medicine.

Real-world efficacy and safety of cabozantinib following immune checkpoint inhibitor failure in Japanese patients with advanced renal cell carcinoma.

BACKGROUND: Real-world data of cabozantinib after failure of immune checkpoint inhibitors for advanced renal cell carcinoma in Japanese population are limited. Additionally, prognostic factors of cabozantinib in this setting are still unknown. METHODS: We retrospectively evaluated data of 56 patients treated with cabozantinib subsequent to failed immune checkpoint inhibitors at four institutions. Regarding the efficacy profile, progression-free survival, overall survival and objective response rate were assessed. In terms of the safety profile, rate of adverse events, dose reduction and treatment interruption were assessed. Furthermore, risk factors of progression-free survival were analyzed. RESULTS: Twenty-nine patients (52%) were treated with cabozantinib as second-line therapy. Most frequent prior immune checkpoint inhibitor treatment was nivolumab plus ipilimumab combination therapy as first-line therapy (n = 30, 54%). Median progression-free survival and overall survival were 9.76 and 25.5 months, respectively, and objective response rate was 34%. All patients experienced at least one adverse event, and grade ≥ 3 adverse events were observed in 31 patients (55%). Forty-four (79%) and 31 (55%) patients needed dose reduction and treatment interruption, respectively. Multivariate analysis showed that reduced initial dose (i.e. <60 mg) (hazard ratio: 2.50, P = 0.0355) and presence of lymph node metastasis (hazard ratio: 2.50, P = 0.0172) were independent factors of shorter progression-free survival. CONCLUSION: Cabozantinib in Japanese patients with advanced renal cell carcinoma who failed immune checkpoint inhibitors was efficacious and had a manageable safety profile. These results appear to be similar to those of previous clinical trials.

Association between lung immune prognostic index and survival of patients with metastatic urothelial carcinoma treated with pembrolizumab.

INTRODUCTION AND OBJECTIVE: Lung immune prognostic index score (LIPI), calculated using the derived neutrophil-lymphocyte ratio and lactate dehydrogenase level, is reported for use in numerous malignancies, while its role on metastatic urothelial carcinoma (mUC) treated with pembrolizumab remains limited. We aimed to investigate association between LIPI and outcomes in this setting. METHODS: We retrospectively evaluated 90 patients with mUC treated with pembrolizumab at four institutions. The associations between three LIPI groups and progression-free survival (PFS), overall survival (OS), objective response rates (ORRs) or disease control rates (DCRs) were assessed. RESULTS: Based on the LIPI, good, intermediate, and poor groups were observed in 41 (45.6%), 33 (36.7%), and 16 (17.8%) patients, respectively. The PFS and OS were significantly correlated with the LIPI (median PFS: 21.2 vs. 7.0 vs. 4.0 months, p = 0.001; OS: 44.3 vs. 15.0 vs. 4.2 months, p < 0.001 in the LIPI good vs. intermediate vs. poor groups). Multivariable analysis further revealed that LIPI good (vs. intermediate or poor, hazard ratio: 0.44, p = 0.004) and performance status = 0 (p = 0.015) were independent predictors of a longer PFS. In addition, LIPI good (hazard ratio: 0.29, p < 0.001) were shown to be associated with a longer OS together with performance status = 0 (p < 0.001). The ORRs tended to be different among patients with Good LIPI compared with Poor, and DCRs were significantly different among the three groups. CONCLUSIONS: LIPI, a simple and convenient score, could be a significant prognostic biomarker of OS, PFS, and DCRs for mUC treated with pembrolizumab.

Comparison of surgical invasiveness between micro-endoscopic discectomy/microscopic discectomy and conventional hemilaminectomy in dogs.

Micro-endoscopic discectomy (MED) or microscopic discectomy (MD) have been performed for disc herniation in humans. The purpose of this study was to compare the invasiveness of the hemilaminectomy in dogs between the approach using a cylindrical retractor for the MED/MD and a conventional open surgical approaches in dogs. First, as preliminary studies, we analyzed the suitability of the cylindrical retractor for the vertebral body of small to medium-sized dogs on the X-ray computed tomographic images using the three-dimensional analysis software, and confirmed that it was possible to open a bone window of an approximate length of 1.72 clto the spinal canal with the cylindrical retractor with a diameter 17 mm using two medium-sized canine cadavers. Next, to determine difference in the invasiveness of hemilaminectomy, the magnitude of tissue damage, surgical stress and postoperative pain were compared between the conventional open approach (hemilaminectomy group: HL group, n=6) and the surgical approach using the cylindrical retractor (MD group, n=6) in 12 beagle dogs. The plasma creatine phosphokinase, C-reactive protein and cortisol concentrations, incision length and University of Melbourne Pain Scale scores after the hemilaminectomy were significantly lower in the MD group than in the HL group. There were no significant differences between the durations of surgery and the other evaluated indices. The approach using the MD can provide a less invasive hemilaminectomy than the conventional approach in dogs.

Histiocytic sarcoma with spinal necrosis in a dog with progressing non-ambulatory tetraparesis.

Background: Histiocytic sarcoma (HS) is an aggressive malignant neoplasm, and widespread metastasis occurs with a fatal outcome. HS involving the central nervous system is relatively uncommon. Spinal cord necrosis, a very rare condition, could be induced by ischemia or infarction. Here, we report a dog progressing non-ambulatory tetraparesis with spinal cord necrosis caused by HS. Case Description: A 9-year-old male Labrador Retriever was presented with a progressing non-ambulatory tetraparesis. CT imaging revealed lysis of the spinous process of T7 and a ring-shaped lesion surrounding the soft tissue of lung fields. T2-weighted MRI showed the spinous processes of T6 to T8 as hyperintense, and the lesion infiltrated into the T7 vertebra and the spinal cord. After euthanasia, the final diagnosis upon necropsy was HS, which was observed in the lung, spinous process, thoracic cord, and the pulmonary hilar lymph node. Moreover, necrotic spots were spread widely through the thoracic spinal cord. Conclusion: This report outlines a case of canine HS in the lung, spinous process, thoracic cord, and pulmonary hilar lymph node. Ischemic deficit and necrosis of the thoracic spinal cord resulted from the compression of perivascular tumor cells, which rapidly led to progressive tetraparesis. Although the diagnosis was difficult, MRI and CT images helped determine the prognosis. To our knowledge, this is the first case report of canine HS with direct spinal cord involvement associated with spinal necrosis.

Impact of sex on prognosis in patients with advanced renal cell carcinoma treated with immune checkpoint inhibitors.

BACKGROUND: Prognostic impact of sex in patients with malignancies treated with immune checkpoint inhibitors has been intensively discussed but remains unclear, especially in advanced renal cell carcinoma. METHODS: We retrospectively evaluated a total of 184 patients with advanced renal cell carcinoma treated with either nivolumab plus ipilimumab combined treatment as first-line therapy (n = 73) or nivolumab as later-line therapy (n = 111) at our affiliated institutions. Progression-free survival, overall survival and objective response rate as well as adverse event profile were compared between sexes. RESULTS: Of the total 184 patients, 48 (26%) were female. Female patients had a significantly shorter progression-free survival than male patients (median: 3.8 vs. 8.3 months, P = 0.0005), but overall survival (median: 39.2 vs. 45.1 months, P = 0.283) and objective response rate (29% vs. 42%, P = 0.119) were not different between them. Similar findings were observed when analyzing within each treatment; in both patient groups treated with nivolumab plus ipilimumab combined therapy and nivolumab monotherapy, progression-free survival was significantly shorter in female than in male patients (P = 0.007, P = 0.017), but overall survival (P = 0.914, P = 0.117) and objective response rate (P = 0.109, P = 0.465) were comparable between them. Moreover, in a more restricted cohort consisting of patients with clear-cell renal cell carcinoma, a shorter progression-free survival in female patients was also observed (3.8 vs. 11.0 months, P < 0.0001). CONCLUSIONS: This retrospective study showed that immune checkpoint inhibitors-based treatment for renal cell carcinoma exhibited less marked effects in female than in male patients. Thus, sex may be an important factor for decision-making on systemic therapy as renal cell carcinoma treatment, although further studies are required to validate the present findings.

Comparison of Outcomes Between Therapeutic Combinations Based on Immune Checkpoint Inhibitors or Tyrosine Kinase Inhibitor Monotherapy for First-Line Therapy of Patients with Advanced Renal Cell Carcinoma Outside of Clinical Trials: A Real-World Retrospective Multi-Institutional Study.

BACKGROUND: Clinical trials have demonstrated the superior efficacy of immune checkpoint inhibitor (ICI)-based combination therapy over sunitinib, a multi-target tyrosine kinase inhibitor (TKI), in patients with advanced renal cell carcinoma. However, such benefits have not been elucidated in populations outside of clinical trials. METHODS: We retrospectively evaluated data from 467 patients with advanced renal cell carcinoma who received ICI-based combination therapy or TKIs, as first-line therapy. Clinical outcome was compared between ICI-based combination therapy and TKIs in each population divided according to trial eligibility. RESULTS: Among 152 patients treated with ICI-based combination therapy and 315 patients treated with TKIs, 76 (50.0%) and 156 (49.5%) were trial ineligible, respectively. Overall survival (p = 0.0072) and objective response rate (p < 0.0001) were significantly higher in ICI-based combination therapy than in TKIs, but progression-free survival was comparable (p = 0.681). In the trial-eligible population, overall survival was longer (p = 0.0906) and the objective response rate was significantly higher (p = 0.0124) in ICI-based combination therapy than in TKIs. In the trial-ineligible population, overall survival (p = 0.0208) and objective response rate (p = 0.0006) were significantly higher with ICI-based combination therapy than with TKIs. A multivariate analysis also showed that ICI-based combination therapy was independently associated with prolonged overall survival (hazard ratio, 0.47; p = 0.0016). Regardless of trial eligibility, progression-free survival did not differ between ICI-based combination therapy and TKIs (trial eligible: p = 0.287; trial ineligible: p = 0.0708). CONCLUSIONS: The present study, using real-world data, provides evidence indicating the therapeutic benefit of ICI-based combination therapy over TKIs for advanced renal cell carcinoma was more statistically significant in the trial-ineligible population than in the trial-eligible population.

Comparison of the Impact of Immune-Related Adverse Events Due to Immune Checkpoint Inhibitor Dual Combination Therapy and Immune Checkpoint Inhibitor Plus Tyrosine Kinase Inhibitor Combination Therapy in Patients with Advanced Renal Cell Carcinoma.

BACKGROUND: The prognostic impact of immune-related adverse events during immune checkpoint inhibitor-based combination therapy for advanced renal cell carcinoma remains unclear, especially in terms of differences between regimens. OBJECTIVE: We aimed to clarify the prognostic impact of immune-related adverse events in patients with advanced renal cell carcinoma receiving immune checkpoint inhibitor dual combination therapy (IO-IO) or immune checkpoint inhibitor plus tyrosine kinase inhibitor combination therapy (IO-TKI). METHODS: We retrospectively evaluated the data of 148 patients who received immune checkpoint inhibitor-based combination therapy as first-line therapy. Patients were divided into two groups based on regimens, namely IO-IO and IO-TKI. The associations between immune-related adverse event development and outcomes, such as progression-free survival, overall survival, and objective response rate, were compared between the two groups. RESULTS: In the IO-IO and IO-TKI groups, 67 of 91 (74%) and 31 of 57 (54%) patients, respectively, experienced at least one immune-related adverse event and the rate was significantly higher in the IO-IO group (p = 0.0204), where immune-related adverse events development was significantly associated with longer progression-free survival (p < 0.0001) and overall survival (p = 0.0102), and a higher objective response rate (p = 0.0028). A multivariate analysis revealed immune-related adverse event development as an independent factor for longer progression-free survival (hazard ratio, 0.25; p < 0.0001) and overall survival (hazard ratio, 0.42; p = 0.0287). There were no significant associations between immune-related adverse events and progression-free survival, overall survival, or objective response rate in the IO-TKI group. CONCLUSIONS: The development of immune-related adverse events was positively associated with the outcome of patients with advanced renal cell carcinoma treated with IO-IO combination therapy; no such correlation was observed for IO-TKI combination therapy.

Impact of Body Mass Index on Outcomes in an Asian population of Advanced Renal Cell Carcinoma and Urothelial Carcinoma Treated With Immune Checkpoint Inhibitors.

OBJECTIVES: To clarify the impact of body mass index (BMI) on treatment outcomes including survival, tumor response, and adverse events (AEs) in patients with advanced renal cell carcinoma (RCC) or urothelial carcinoma (UC) treated with immune checkpoint inhibitors (ICIs) in an Asian population. METHODS: We retrospectively evaluated 309 patients with advanced RCC or UC who received ICIs between September 2016 and July 2021. The patients were divided into high- (i.e., ≥25 kg/m2) and low-BMI (<25 kg/m2) groups according to the BMI at the time of treatment initiation. RESULTS: Overall, 57 patients (18.4%) were classified into the high-BMI group. In RCC patients treated with ICIs as first-line therapy or UC treated with pembrolizumab, progression-free survival (PFS) (p = 0.309; p = 0.842), overall survival (OS) (p = 0.701; p = 0.983), and objective response rate (ORR) (p = 0.163; p = 0.553) were comparable between the high- and low-BMI groups. In RCC patients treated with nivolumab monotherapy as later-line therapy, OS (p = 0.101) and ORR (p = 0.102) were comparable, but PFS was significantly longer in the high-BMI group (p = 0.0272). Further, multivariate analysis showed that BMI was not an independent factor of PFS or OS in all the treatment groups (any, p>0.05). As for AE profiles, in nivolumab monotherapy, the rate was significantly higher in the high-BMI group (p = 0.0203), whereas in the other two treatments, the rate was comparable. CONCLUSIONS: BMI was not associated with survival or response rates of advanced RCC or UC patients treated with ICIs in an Asian population. AEs might frequently develop in high-BMI patients with RCC in nivolumab monotherapy.

Establishment of a New Canine Inflammatory Mammary Carcinoma Cell Line and Analysis of its Cystine-glutamate Transporter Subunit Expression.

Introduction: Inflammatory mammary carcinoma (IMC) is a rare disease with a poor prognosis and one affecting dogs. Inflammatory breast carcinoma (IBC) is a subtype of malignant breast cancer in humans with a high degree of malignancy and a similarly poor prognosis. Since the clinical symptoms and prognoses of both are similar, canine IMC has been considered as a model of human IBC. In this study, we newly established a stable IMC-derived cell line from a patient at the Yamaguchi University Animal Medical Center in Japan. Material and Methods: The patient was a female toy poodle presenting with an inflamed mammary gland, which was diagnosed as IMC. The cell line was established from a tissue biopsy. Surface antigen marker (CD24 and CD44) expression was determined. Cystine/glutamate antiporter (xCT) expression was determined by Western blotting, flow cytometry and fluorescence immunostaining, and sulfasalazine was administered to ascertain if it suppressed xCT expression. Stem cell marker (Nanog, Sox2, Myc and Klf4) expression and aldehyde dehydrogenase (ALDH) activity were also investigated. Results: The cultured cells showed xCT, and its suppression showed downregulation of stem cell markers and ALDH activity. Stable cell proliferation was verified. Conclusion: A new canine IMC-derived cell line was established. In the future, we aim to study the effect of xCT on the maintenance of cancer stem cell properties in canine tumours, and propose a new therapeutic method for the treatment of canine IMC by targeting xCT.

Outcomes of megavoltage radiotherapy for canine intranasal tumors and its relationship to clinical stages.

Background: Radiation therapy is considered important for the treatment of intranasal tumors in dogs and is believed to be essential for prolonging their survival. Aim: To investigate the contribution of clinical staging to improve outcomes of megavoltage radiotherapy for canine intranasal tumors. Methods: A total of 123 dogs with intranasal tumors were included in the study. Forty-eight dogs received orthovoltage radiotherapy after cytoreductive surgery (Group I), 21 received orthovoltage radiotherapy without surgery (Group II), and 54 received megavoltage radiotherapy without surgery (Group III). All cases in each group were classified into clinical stages 1-4, and the median survival time (MST) was compared for each stage in all groups. Results: The overall MST was not significantly difference among Group I (325 days), Group II (317 days), and Group III (488 days); however, Group III was prolonged than Groups I and II. The MSTs for stages 1, 2, 3, and 4 were 597, 361, 267, and 325 days in Group I; 633, 260, 233, and 329 days in Group II; and 931, 860, 368, and 176 days in Group III, respectively. The MST for stage 2 cases in Group III was significantly prolonged when compared with that in Groups I and II; no significant difference was observed at other stages; however, the MST in Group III was longer in stage 1. These results showed that megavoltage radiotherapy prolonged the MST in dogs with intranasal tumors when compared to orthovoltage radiation with or without cytoreductive surgery, and that improvements in MST at stage 2 contributed significantly to this. Conclusion: The improvement in the MST in dogs with stages 1 and 2 intranasal tumors highlights the importance of starting megavoltage radiotherapy in the early stages.

Adjustment of multi-leaf collimator parameters in 4-MV and 6-MV IMRT: A study of veterinary clinical cases.

Background: For optimal treatment, it is important to maintain optimal multi-leaf collimator (MLC) transmission in intensity-modulated radiation therapy (IMRT). However, adjustment of transmissions has not been reported in veterinary medicine. Aim: To demonstrate that appropriate MLC parameter adjustment for IMRT using 4- and 6-MV energy can reduce the need for quality assurance revalidation in real companion animal clinical cases. Methods: The MLC parameters (leaf transmission and leaf offset) of the treatment planning system were adjusted by evaluating seven plans (10 × 10 cm, 3ABUT, DMLC, 7segA, FOURL, HDMLC, and HIMRT) and 20 preclinical cases (10 cases each in 4- and 6-MV groups). Subsequently, 101 IMRT plans of 88 cases (77 dogs and 11 cats) were evaluated for absolute dose of plan target volume (PTV) and organs at risk (OAR) and were analyzed for the relative dose distribution by gamma analysis (3%/3 mm, >10%) using EBT3 film. Results: After adjustment of the MLC parameters (leaf transmission and leaf offset, 4 MV: 0.008 and 0, 6 MV: 0.005 and 0, respectively), the data from 101 plans (4 MV: 64 plans and 6 MV: 37 plans) treated with IMRT showed PTV <3%, OAR <5%, and gamma analysis pass rates ≥95% in all cases. Conclusion: Clinically meaningful dose distributions can be created even with a limited validation device if the treatment parameters are adjusted appropriately, even for tumors in canines and felines, where the irradiation field is small, the target is adjacent to the OAR, and the target is often superficial.

Therapeutic role of deferred cytoreductive nephrectomy in patients with metastatic renal cell carcinoma treated with nivolumab plus ipilimumab.

OBJECTIVES: To explore the therapeutic role of deferred cytoreductive nephrectomy in patients with metastatic renal cell carcinoma treated with nivolumab plus ipilimumab. PATIENTS AND METHODS: Forty-one patients with synchronous metastatic renal cell carcinoma who received nivolumab plus ipilimumab as first-line systemic therapy at our affiliated institutions were retrospectively evaluated. We focused on the prognosis, including tumor responses in primary kidney and metastatic lesions in patients treated with deferred cytoreductive nephrectomy. In addition, the overall survival according to nephrectomy status (i.e. deferred cytoreductive nephrectomy vs. upfront cytoreductive nephrectomy vs. without cytoreductive nephrectomy) was compared. RESULTS: During a median follow-up period of 12.0 months, seven (30%) patients received deferred cytoreductive nephrectomy at a median time of 10.4 months after nivolumab plus ipilimumab initiation. All the patients showed tumor shrinkage in their primary kidney lesions, including six (86%) patients with ≥30% of shrinkage. Metastatic lesions were also shrunk by ≥30% in six (86%) patients, including two (29%) obtaining complete response. At the last time of follow-up, three (43%) patients were disease-free. The overall survival rate after nivolumab plus ipilimumab initiation tended to be higher in patients with deferred cytoreductive nephrectomy compared with those with upfront cytoreductive nephrectomy (1-year survival rate: 100% vs. 72.4%, P = 0.0587) and those without cytoreductive nephrectomy (vs. 58.2%, P = 0.0613). CONCLUSIONS: The present retrospective data showed that deferred cytoreductive nephrectomy had the potential to exert a therapeutic effect in a subset of patients who obtained favorable tumor responses to nivolumab plus ipilimumab for a certain period. Prospective randomized clinical trials are needed to confirm the prognostic impact of deferred cytoreductive nephrectomy after frontline immunotherapy in synchronous metastatic renal cell carcinoma.

Efficacy and Safety of Immunotherapy-Based Combinations as First-Line Therapy for Metastatic Renal Cell Carcinoma in Patients Who Do Not Meet Trial Eligibility Criteria.

BACKGROUND: Data regarding the efficacy and safety profiles of immune checkpoint inhibitors (ICIs) for metastatic renal cell carcinoma (mRCC) trial-ineligible patients in the real world remain unclear. OBJECTIVES: The aim of this study was to clarify the impact of trial eligibility on ICI-based combination therapy for mRCC. PATIENTS AND METHODS: We collected clinical data of mRCC patients receiving ICIs since 2016, and 222 patients were registered. Among these patients, we evaluated 93 patients treated with ICI-based combination therapy, including nivolumab plus ipilimumab, pembrolizumab plus axitinib, or avelumab plus axitinib, as first-line therapy. Patients were classified into the trial-ineligible group when they had at least one of the following factors at the time of treatment initiation: Karnofsky performance status (KPS) < 70%, hemoglobin level < 9.0 g/dL, estimated glomerular filtration rate (eGFR) < 40 mL/min/1.73 m2, platelet count < 100,000/µL, neutrophil count < 1500/µL, non-clear cell histology, or brain metastasis. The remaining patients were classified into the trial-eligible group. RESULTS: Forty-eight patients (52%) were classified into the trial-ineligible group. The frequency of patients with trial-ineligible factors was highest for low eGFR (n = 20, 45%), followed by non-clear cell histology (n = 17, 36%) and low KPS score (n = 12, 25%). There was no significant difference in progression-free survival (median: 24.0 vs. 11.0 months, p = 0.416), overall survival (1-year rate: 87.0% vs. 85.3%, p = 0.634), or objective response rate (52% vs. 42%, p = 0.308) between the trial-eligible and -ineligible patients. The incidence rate of adverse events was higher in the trial-eligible patients than in the trial-ineligible patients (91% vs. 75%, p = 0.0397); however, the rate of grade 3 or higher adverse events was comparable between the two groups (42% vs. 40%, p = 0.796). CONCLUSIONS: There are many trial-ineligible patients in the real world. Nevertheless, the efficacy and safety of ICI-based combination therapy in trial-ineligible patients were non-inferior compared with those of trial-eligible patients.