High response rate with extended dosing of cemiplimab in advanced cutaneous squamous cell carcinoma.

BACKGROUND: Cemiplimab (Libtayo®), a human monoclonal immunoglobulin G4 antibody to the programmed cell death-1 receptor, is approved for the treatment of patients with advanced cutaneous squamous cell carcinoma (CSCC), who are not candidates for curative surgery or curative radiation, using an every-3-weeks (Q3W) dosing interval. Pharmacokinetic modeling indicated that Ctrough of extended intravenous dosing of 600 mg every 4 weeks (Q4W) would be comparable to the approved intravenous dosage of 350 mg Q3W. We examined the efficacy, pharmacokinetics, and safety of cemiplimab dosed Q4W. METHODS: In this open-label, phase II trial (ClinicalTrials.gov identifier NCT02760498), the cohort of patients ≥18 years old with advanced CSCC received cemiplimab 600 mg intravenously Q4W for up to 48 weeks. Tumor measurements were recorded every 8 weeks. The primary endpoint was objective response rate by independent central review. RESULTS: Sixty-three patients with advanced CSCC were treated with cemiplimab. The median duration of follow-up was 22.4 months (range: 1.0-39.8). An objective response was observed in 39 patients (62%; 95% CI: 48.8% to 73.9%), with 22% of patients (n=14) achieving complete response and 40% (n=25) achieving partial response. The most common treatment-emergent adverse events were diarrhea, pruritus, and fatigue. CONCLUSIONS: Extended dosing of cemiplimab 600 mg intravenously Q4W exhibited substantial antitumor activity, rapid and durable responses, and an acceptable safety profile in patients with advanced CSCC. These results confirm that cemiplimab is a highly active therapy for advanced CSCC. Additional data would help ascertain the benefit-risk profile for the 600 mg intravenous dosing regimen compared with the approved regimen.

An elusive prostate tumour: Metastatic microcystic cribriform carcinoma presenting with imaging-histologic discordance.

Microcystic adenocarcinoma is an uncommon histologic variant of prostate carcinoma. Despite its rarity, it has gained increasing recognition over the past decade for its diagnostic challenges and unclear prognostic significance. Herein, we describe a rare case of metastatic microcystic prostate adenocarcinoma, presenting with discordance between imaging and histologic findings. This report highlights the diagnostic and therapeutic challenges of this pathological entity and the importance of multidisciplinary collaboration in the management of intermediate-risk prostate cancer.

Immune checkpoint inhibitor therapy for advanced cutaneous squamous cell carcinoma in Australia: a retrospective real world cohort study.

OBJECTIVES: To review the outcomes of immune checkpoint inhibitor (ICI) treatment of advanced cutaneous squamous cell carcinoma (CSCC) outside clinical trials. STUDY DESIGN: Retrospective observational study; review of patient records in fifteen Australian institutions. SETTING, PARTICIPANTS: All Australian adults with locally advanced or metastatic CSCC not amenable to curative surgery or radiotherapy treated with ICIs, 5 May 2017 - 23 May 2022, through a cemiplimab compassionate access scheme (Therapeutic Goods Administration Special Access Scheme) or who personally covered the cost of pembrolizumab prior to the start of the access scheme. MAIN OUTCOME MEASURES: Best overall response rate (ORR) according to standardised assessment criteria using the hierarchy: Response Evaluation Criteria in Solid Tumors (RECIST 1.1), the modified World Health Organization clinical response criteria, and the Positron Emission Tomography Response Criteria (PERCIST 1.0); overall and progression-free survival. RESULTS: A total of 286 people with advanced CSCC received ICI therapy during May 2017 - May 2022 (cemiplimab, 270; pembrolizumab, 16). Their median age was 75.2 years (range, 39.3-97.5 years) and 232 were men (81%); median follow-up time was 12.2 months (interquartile range, 5.5-20.5 months). Eighty-eight people (31%) were immunocompromised, 27 had autoimmune disease, and 59 of 277 (21%) had ECOG performance scores of 2 or 3. The ORR was 60% (166 of 278 evaluable patients): complete responses were recorded for 74 (27%) and partial responses for 92 patients (33%). Twelve-month overall survival was 78% (95% confidence interval [CI], 72-83%); progression-free survival was 65% (95% CI, 58-70%). Poorer ECOG performance status was associated with poorer overall survival (per unit: adjusted hazard ratio [aHR], 3.0; 95% CI, 2.0-4.3) and progression-free survival (aHR, 2.4; 95% CI, 1.8-3.3), as was being immunocompromised (overall: aHR, 1.8; 95% CI, 1.1-3.0; progression-free: aHR, 1.8; 95% CI, 1.2-2.7). Fifty-five people (19%) reported immune-related adverse events of grade 2 or higher; there were no treatment-related deaths. CONCLUSION: In our retrospective study, the effectiveness and toxicity of ICI therapy were similar to those determined in clinical trials. Our findings suggest that ICIs could be effective and well tolerated by people with advanced CSCC who are ineligible for clinical trials.

Pembrolizumab with Chemoradiation as Treatment for Muscle-invasive Bladder Cancer: Analysis of Safety and Efficacy of the PCR-MIB Phase 2 Clinical Trial (ANZUP 1502).

BACKGROUND: Radiation may improve the efficacy of immune checkpoint inhibition. This study investigates the combination of pembrolizumab and chemoradiation (CRT) for muscle-invasive bladder cancer (MIBC). OBJECTIVE: To assess the feasibility and safety of pembrolizumab combined with CRT for MIBC. DESIGN, SETTING, AND PARTICIPANTS: A single-arm phase 2 trial was performed with 28 participants having cT2-T4aN0M0 MIBC (Eastern Cooperative Oncology Group performance status 0-1; estimated glomerular filtration rate ≥40 ml/min; no contraindications to pembrolizumab) suitable for CRT. INTERVENTION: Whole bladder radiation therapy (RT; 64 Gy in 32 daily fractions, over 6.5 wk, combined with cisplatin (35 mg/m2 intravenously [IV] weekly, six doses) and pembrolizumab (200 mg IV q3 weeks, seven doses), both starting with RT. Surveillance cystoscopy/biopsy and computerised tomography scans performed 12 and 24 wk after CRT. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoint was feasibility, determined by a prespecified satisfactory low rate of grade 3 or worse nonurinary toxicity or completion of planned CRT according to defined parameters. Secondary endpoints were complete cystoscopic response, locoregional progression-free survival (LRPFS), distant metastasis-free survival (DMFS), and overall survival (OS). RESULTS AND LIMITATIONS: Twenty-eight patients were enrolled with a 31-mo median follow-up. Six had Grade >3 nonurinary adverse events during/within 12 wk after treatment; three had more than one cisplatin dose reduction. The 24-wk post-CRT complete response (CR) rate was 88%. Eight patients developed metastatic disease, and three had nonmetastatic progression. The DMFS at 2 yr is 78% (95% confidence interval [CI] 54-90%), with LRPFS at 2 yr of 87% (95% CI 64-96%) and median OS of 39 mo (95% CI 17.1-not evaluable). Limitations are the single-arm design and sample size. CONCLUSIONS: Combining pembrolizumab with CRT for MIBC was feasible, with manageable toxicity and promising CR rates. PATIENT SUMMARY: Immunotherapy treats nonmetastatic/metastatic bladder cancer effectively. We combined pembrolizumab with chemotherapy and radiation to assess its safety and impact on treatment delivery. The combination was feasible with encouraging early activity. Further larger trials are warranted.

Concomitant medication use does not appear to alter long-term efficacy of sonidegib for advanced basal cell carcinoma: a post hoc analysis based on the 42-month BOLT study.

BACKGROUND: Sonidegib is approved to treat locally advanced basal cell carcinoma (laBCC) in patients not amenable to surgery or radiation. The BOLT trial demonstrated durable efficacy of sonidegib in laBCC patients over 42 months. BCC is most common in the elderly, who often take chronic medications. OBJECTIVES: We evaluated the efficacy of sonidegib (200 mg daily) in laBCC patients on select concomitant medications. MATERIALS & METHODS: In the Phase II BOLT study, laBCC patients were randomized 1:2 to sonidegib 200 mg:800 mg daily. The primary endpoint was objective response rate (ORR) per central review. Post hoc assessments included ORR and duration of response (DOR) per investigator review for patients on concomitant medications. RESULTS: At 42 months, ORR for laBCC patients taking sonidegib 200 mg daily (n=66) was 71.2% and DOR was 15.7 months according to investigator review. Patients on select concomitant medications (n=37) had an ORR of 73.0%; DOR was not estimable. CONCLUSION: Administration of sonidegib with concomitant medications, excluding strong cytochrome P450 3A4/5 inhibitors/inducers, does not appear to alter its efficacy in laBCC patients.

Health-related quality of life in patients with melanoma brain metastases treated with immunotherapy.

Aims: To describe the health-related quality of life (HRQoL) of melanoma brain metastasis (MBM) patients throughout the first 18 weeks of ipilimumab-nivolumab or nivolumab treatment. Materials & methods: HRQoL data (European Organisation for Research and Treatment of Cancer's Core Quality of Life Questionnaire, additional Brain Neoplasm Module, and EuroQol 5-Dimension 5-Level Questionnaire) were collected as a secondary outcome of the Anti-PD1 Brain Collaboration phase II trial. Mixed linear modeling assessed changes over time, whereas the Kaplan-Meier method was used to determine median time to first deterioration. Results: Asymptomatic MBM patients treated with ipilimumab-nivolumab (n = 33) or nivolumab (n = 24) maintained baseline HRQoL. MBM patients with symptoms or leptomeningeal/progressive disease treated with nivolumab (n = 14) reported a statistically significant trend toward improvement. Conclusion: MBM patients treated with either ipilimumab-nivolumab or nivolumab did not report a significant deterioration in HRQoL within 18 weeks of treatment initiation. Clinical trial registration: NCT02374242 (ClinicalTrials.gov).

Historically, people whose melanoma had spread to the brain (known as brain metastases) lived only 4­6 months after diagnosis, with less than 15% alive at 12 months. However, the development of immunotherapies such as nivolumab and ipilimumab to treat advanced melanoma has resulted in more than 50% of patients being alive 5 years after diagnosis. With the effectiveness of these immunotherapies demonstrated in clinical trials, we wanted to examine the impact of these treatments on the health-related quality of life of people with melanoma brain metastases. Using data from a clinical trial evaluating the effectiveness of immunotherapies in people diagnosed with melanoma brain metastases, this study investigated the impact of nivolumab and nivolumab combined with ipilimumab on quality of life. We found that neither nivolumab alone nor nivolumab combined with ipilimumab had a negative effect on quality of life. In summary, this study provides further support for the use of these immunotherapies as first-line treatment for melanoma brain metastases.

Genomic Profiling of Metastatic Basal cell Carcinoma Reveals Candidate Drivers of Disease and Therapeutic Targets.

Basal cell carcinomas (BCCs) are human beings' most common malignant tumors. Most are easily managed by surgery or topical therapies, and metastasis is rare. Although BCCs can become locally advanced, metastatic BCCs are very uncommon and may be biologically distinct. We assessed the clinicopathologic characteristics of 17 patients with metastatic BCC and pursued whole-exome sequencing of tumor and germline DNA from 8 patients. Genomic profiling revealed aberrant activation of Hedgehog signaling and alterations in GLI transcriptional regulators and Notch and Hippo signaling. Matched local recurrences of primary BCCs and metastases from 3 patients provided evidence of a clonal origin in all cases. Mutations associated with YAP inhibition were found exclusively in 2 hematogenously-spread lung metastases, and metastatic BCCs were enriched for mutations in the YAP/TAZ-binding domain of TEAD genes. Accordingly, YAP/TAZ nuclear localization was associated with metastatic types and Hippo mutations, suggesting an enhanced oncogenic role in hematogenously-spread metastases. Mutations in RET, HGF, and phosphatidylinositol 3­kinase (PI3K)/protein kinase B (AKT) signaling were enriched compared with a cohort of low clinical-risk BCCs. Our results implicate Hippo and PI3K/AKT dysregulation in metastatic progression of BCCs, making these potential therapeutic targets in metastatic disease. The common clonal origin of matched recurrent and metastatic BCCs suggests that molecular profiling can assist in determining the nature/origin of poorly differentiated metastatic tumors of uncertain type. Genes and pathways enriched for mutations in this cohort are candidate drivers of metastasis and can be used to identify patients at high risk of metastasis who may benefit from aggressive local treatment and careful clinical follow-up.

Nivolumab Plus Ipilimumab Versus EXTREME Regimen as First-Line Treatment for Recurrent/Metastatic Squamous Cell Carcinoma of the Head and Neck: The Final Results of CheckMate 651.

PURPOSE: CheckMate 651 (ClinicalTrials.gov identifier: NCT02741570) evaluated first-line nivolumab plus ipilimumab versus EXTREME (cetuximab plus cisplatin/carboplatin plus fluorouracil ≤ six cycles, then cetuximab maintenance) in recurrent/metastatic squamous cell carcinoma of the head and neck (R/M SCCHN). METHODS: Patients without prior systemic therapy for R/M SCCHN were randomly assigned 1:1 to nivolumab plus ipilimumab or EXTREME. Primary end points were overall survival (OS) in the all randomly assigned and programmed death-ligand 1 combined positive score (CPS) ≥ 20 populations. Secondary end points included OS in the programmed death-ligand 1 CPS ≥ 1 population, and progression-free survival, objective response rate, and duration of response in the all randomly assigned and CPS ≥ 20 populations. RESULTS: Among 947 patients randomly assigned, 38.3% had CPS ≥ 20. There were no statistically significant differences in OS with nivolumab plus ipilimumab versus EXTREME in the all randomly assigned (median: 13.9 v 13.5 months; hazard ratio [HR], 0.95; 97.9% CI, 0.80 to 1.13; P = .4951) and CPS ≥ 20 (median: 17.6 v 14.6 months; HR, 0.78; 97.51% CI, 0.59 to 1.03; P = .0469) populations. In patients with CPS ≥ 1, the median OS was 15.7 versus 13.2 months (HR, 0.82; 95% CI, 0.69 to 0.97). Among patients with CPS ≥ 20, the median progression-free survival was 5.4 months (nivolumab plus ipilimumab) versus 7.0 months (EXTREME), objective response rate was 34.1% versus 36.0%, and median duration of response was 32.6 versus 7.0 months. Grade 3/4 treatment-related adverse events occurred in 28.2% of patients treated with nivolumab plus ipilimumab versus 70.7% treated with EXTREME. CONCLUSION: CheckMate 651 did not meet its primary end points of OS in the all randomly assigned or CPS ≥ 20 populations. Nivolumab plus ipilimumab showed a favorable safety profile compared with EXTREME. There continues to be a need for new therapies in patients with R/M SCCHN.

Metastatic primary breast neuroendocrine neoplasms: a case series.

BACKGROUND: Breast neuroendocrine neoplasms represent a rare subtype of breast cancer which have not been well studied or characterised, particularly in the metastatic setting. AIM: To present clinicopathological characteristics, treatment and outcomes of a series of patients with metastatic neuroendocrine carcinoma of the breast and review the current literature. METHODS: We performed a retrospective review to identify and describe patients with metastatic neuroendocrine carcinoma of the breast at our centre between 2011 and 2021. Medical records, pathology and imaging results were examined to evaluate the clinical and histopathological features as well as the treatment pathways and prognosis of these patients. RESULTS: We present a series of seven female patients with metastatic neuroendocrine carcinoma of the breast, as defined by the World Health Organization classification, over a period of 10 years (2011-2021) from a single centre. Median age at diagnosis was 48 years (range 39-63). Six of seven tissue samples expressed synaptophysin and chromogranin and were also oestrogen and progesterone receptor positive; median Ki-67 index was 50% (range 20-90%). All seven patients had demonstrated avidity on 18 F-FDG PET imaging, and the six who underwent 68 Ga-DOTATATE PET all had significant avidity. Treatment modalities and sequencing varied, but all patients received chemotherapy during their disease course. Six patients received three or more lines of treatment. Median overall survival was 31.8 months (range 3.7-108.6). Median progression-free survival (PFS) with first-line therapy for metastatic disease was 5.8 months (range 1.8-37.8). CONCLUSIONS: This series shows the use of multiple modalities in treating this disease, with different sequencing in different patients. Despite multiple modalities used in the first-line setting, first-line PFS remains short. Larger series and further molecular characterisation are required to aid clinicians in managing this condition and to guide optimal treatment sequencing to improve outcomes in this rare patient group.

Second primary malignancies in chronic lymphocytic leukaemia: Skin, solid organ, haematological and Richter's syndrome.

Chronic lymphocytic leukaemia (CLL) is invariably accompanied by some degree of immune failure, and CLL patients have a high rate of second primary malignancy (SPM) compared to the general population. We comprehensively documented the incidence of all forms of SPM including skin cancer (SC), solid organ malignancy (SOM), second haematological malignancy (SHM) and separately Richter's syndrome (RS) across all therapy eras. Among the 517 CLL/small lymphocytic lymphoma (SLL) patients, the overall incidence of SPMs with competing risks was SC 31.07%, SOM 25.99%, SHM 5.19% and RS 7.55%. Of the 216 treated patients, 106 (49.1%) had at least one form of SPM, and 63 of 106 (29.2% of treated patients) developed an SPM 1.5 years (median) after treatment for their CLL. Melanoma accounted for 30.3% of SC. Squamous cell carcinoma (SCC), including eight metastatic SCCs, was 1.8 times more than basal cell carcinoma (BCC), a reversal of the typical BCC:SCC ratio. The most common SOMs were prostate (6.4%) and breast (4.5%). SHM included seven acute myeloid leukaemia (AML) and five myelodysplasia (MDS) of which eight (four AML, four MDS) were therapy-related. Any SPM occurred in 32.1% of 53 Monoclonal B-lymphocytosis (MBL) patients. Age-adjusted standardised rates of SPM (per 100,000) for CLL, MBL and the general Australian population were 2648, 1855 and 486.9, respectively. SPMs are a major health burden with 44.9% of CLL patients with having at least one SPM, and apart from SC, associated with significantly reduced overall survival. Dramatic improvements in CLL treatment and survival have occurred with immunochemotherapy and targeted therapies, but mitigating SPM burden will be important to sustain further progress.

Outcome of patient with myasthenia gravis with the use of immunotherapy in metastatic Merkel cell carcinoma.

We report on a 79-year-old man diagnosed with localized Merkel cell carcinoma (MCC) who also had acetylcholine receptor antibody (Ach-R-Ab)-positive myasthenia gravis (MG) controlled on prednisolone, mycophenolate and intravenous immunoglobulin (IVIG). His MCC was initially treated with radiation, followed by chemotherapy on metastatic recurrence. Chemotherapy initially stabilized the disease, but he experienced significant fatigue and his disease progressed within 3 months. After careful consideration of the risk of a myasthenic crisis, he was commenced on avelumab. He had initial partial response, though he ultimately developed progressive disease which led to a decision for best supportive care at 10 months post starting immunotherapy. Importantly, as per spirometry, his MG remained stable throughout immunotherapy. We present the current case to demonstrate that MG should not be viewed as an absolute contraindication to immunotherapy in scenarios where there are limited alternate therapeutic options.

Using drug scheduling to manage adverse events associated with hedgehog pathway inhibitors for basal cell carcinoma.

Basal cell carcinoma (BCC) is the most common malignancy and form of skin cancer worldwide; advanced BCC, either as locally advanced BCC (laBCC) or metastatic BCC (mBCC), can cause substantial tissue invasion and morbidity. Until the recent availability of the hedgehog pathway inhibitors (HHIs) sonidegib and vismodegib, treatment options for advanced BCC were limited. These agents demonstrate efficacy in patients with laBCC and mBCC; however, the adverse events (AEs) associated with these agents can lead to treatment interruption or discontinuation and reduced quality of life, all of which significantly impact long-term adherence to therapy, which might affect clinical outcome. Given that most AEs are class-related effects, switching HHIs does not appear to lead to a significantly different AE profile, underscoring the importance of maintaining patients on their first HHI. Interrupting treatment of sonidegib and vismodegib does not appear to undermine the efficacy of these agents and is therefore a practical option to manage AEs in order to maintain continued treatment and disease control.

Effects of Sonidegib Following Dose Reduction and Treatment Interruption in Patients with Advanced Basal Cell Carcinoma During 42-Month BOLT Trial.

INTRODUCTION: Sonidegib is a Hedgehog pathway inhibitor approved to treat locally advanced basal cell carcinoma and, depending on regulatory approval, metastatic basal cell carcinoma. Results from the BOLT study demonstrated robust efficacy and continued tolerability through 42 months. This analysis evaluated the impact of sonidegib dose reductions and interruptions in patients with advanced basal cell carcinoma through 42 months. METHODS: BOLT was a randomized, double-blind, multicenter, phase 2 study. Adults with no previous Hedgehog pathway inhibitor therapy were randomized 1:2 to sonidegib 200 or 800 mg once daily. Primary endpoint was objective response rate. Dose modifications were permitted in patients unable to tolerate the dosing schedule or if a treatment-related adverse event was suspected. RESULTS: The incidence of dose interruptions was similar between the 200- and 800-mg groups (68.4% vs 65.3%, respectively). Dose reductions occurred more frequently in patients receiving sonidegib 800 mg (36.7%) than 200 mg (16.5%). Overall response rate for all patients receiving sonidegib 200 mg daily was 48.1% and was similar to those of patients without dose reduction or interruption (48.5%) and patients with at least one dose reduction or interruption (46.2%). CONCLUSION: Dose reductions and interruptions were practical and did not impact the efficacy of sonidegib. In patients with advanced basal cell carcinoma who necessitate long-term treatment, dose interruptions may be beneficial for continued treatment and disease control. TRIAL REGISTRATION: ClinicalTrials.gov identifier, NCT01327053.

Key Clinical Adverse Events in Patients with Advanced Basal Cell Carcinoma Treated with Sonidegib or Vismodegib: A Post Hoc Analysis.

INTRODUCTION: Sonidegib is approved to treat locally advanced basal cell carcinoma (laBCC) in the USA, EU, Switzerland, and Australia and metastatic basal cell carcinoma (mBCC) in Switzerland and Australia in patients not amenable to surgery or radiotherapy. Vismodegib is approved to treat patients with mBCC, recurrent laBCC, or those not candidates for surgery or radiation. There is no head-to-head trial comparing Hedgehog inhibitors. We describe time to onset and severity of adverse events (AEs) in two studies reporting cumulative AE incidence every treatment cycle: the sonidegib phase 2 BOLT study and the expanded-access, open-label vismodegib study. METHODS: This analysis included patients with histologically confirmed laBCC or mBCC from BOLT who received sonidegib 200 mg once daily (QD) and patients from the vismodegib study who received vismodegib 150 mg QD. Cumulative occurrence of AEs and median time to AE onset were calculated on 30-day cycles for sonidegib and 28-day cycles for vismodegib. AEs were graded for severity using the Common Terminology Criteria for Adverse Events. Only common (at least 15% incidence) AEs were analyzed in this study. RESULTS: Over 18 treatment cycles, the most common all-grade AEs for sonidegib and vismodegib were muscle spasm (54.4% vs 70.6%; P = 0.0236), alopecia (49.4% vs 58.0%; no significant difference [NS]), and dysgeusia (43.0% vs 70.6%; P = 0.0003); incidences of diarrhea, nausea, fatigue, and weight decrease were 31.6% vs 25.2% (NS), 39.2% vs 19.3% (P = 0.0032), 32.9% vs 19.3% (P = 0.0429), and 30.4% vs 16.0% (P = 0.0217), respectively. Sonidegib-treated patients had more delayed median time to onset for all AEs than vismodegib-treated patients, except fatigue and weight decrease (NS). Most AEs reported were grade ≤ 2. CONCLUSION: This post hoc analysis suggests lower overall incidence and slower onset of certain AEs in patients treated with sonidegib compared with vismodegib. In the absence of head-to-head comparisons, the relevance of these findings needs further studies to provide conclusive evidence.

Integrated analysis of a phase 2 study of cemiplimab in advanced cutaneous squamous cell carcinoma: extended follow-up of outcomes and quality of life analysis.

BACKGROUND: To provide pooled longer term data from three groups of a phase 2 study of cemiplimab in patients with advanced cutaneous squamous cell carcinoma (CSCC), and to determine duration of response (DOR) and impact on quality of life (QoL). METHODS: Patients received cemiplimab 3 mg/kg every 2 weeks (group 1, metastatic CSCC [mCSCC], n=59; group 2, locally advanced CSCC, n=78) or cemiplimab 350 mg every 3 weeks (group 3, mCSCC, n=56). Primary endpoint was objective response rate (ORR) per independent central review (ICR). QoL was repeatedly measured at day 1 of each treatment cycle (groups 1 and 2: 8 weeks; group 3: 9 weeks). RESULTS: Median duration of follow-up was 15.7 months. Overall, ORR per ICR was 46.1% (95% CI: 38.9% to 53.4%). Complete response (CR) rates were 20.3%, 12.8%, and 16.1% for groups 1, 2, and 3, respectively. Median time to CR was 11.2 months. Among patients with partial response or CR, the estimated proportion of patients with ongoing response at 12 months from the first objective response was 87.8% (95% CI: 78.5% to 93.3%), with median DOR not reached. Kaplan-Meier estimated probability of overall survival (OS) was 73.3% (95% CI: 66.1% to 79.2%) at 24 months, with median OS not reached. Global Health Status (GHS)/QoL improvements were observed as early as cycle 2 and were significantly improved and durable until last assessment. Kaplan-Meier estimate of median time to first clinically meaningful improvement for pain was 2.1 (95% CI: 2.0 to 3.7) months and was significantly improved in responders versus non-responders (p<0.0001). CONCLUSIONS: This is the largest (n=193) clinical dataset for a programmed cell death-1 inhibitor against advanced CSCC, confirming the sustained substantial clinical activity of cemiplimab in these patients, including new findings of improved CR rates over time, increasing DOR, and durable pain control and GHS/QoL improvement. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT02760498), https://clinicaltrialsgov/ct2/show/NCT02760498.

Succinate dehydrogenase-deficient gastrointestinal stromal tumor: from diagnostic dilemma to novel personalised therapy in 2 case reports.

Succinate dehydrogenase (SDH)-deficient gastrointestinal stromal tumor (GIST) is a unique and distinctive subtype of gastric GIST. The literature on this subtype from developing countries is exceedingly sparse. Patients with SDH-deficient GIST often experience a lack or delay in genomic profiling, despite stereotypical clinicopathologic features, potentially resulting in sub-optimal management. SDH-deficient GISTs are highly syndromic, typically have more indolent behavior, a prognosis not predicted by size and mitotic rate, a tendency to lymph node metastases, and are insensitive to standard tyrosine kinase inhibitors (TKIs). We report two women with SDH-deficient GIST. In the first case, SDH deficiency was identified late due to lack of awareness and poor access to diagnostic facilities. The patient progressed through TKI therapy, but responded to temozolomide, which is under investigation in clinical trials. In the second case, SDH deficiency was identified at diagnosis, and the patient responded well to 177Lutetium peptide radionuclide receptor therapy (PRRT) after progressing through two lines of TKIs. We aim to highlight the need for more awareness and access to genomic diagnostic facilities for GIST patients, temozolomide as a novel therapy for SDH-deficient GIST, and the potential value of DOTATATE positron emission tomography (PET) and PRRT as a novel imaging modality and therapy for TKI insensitive GIST patients.

The changing paradigm of managing Merkel cell carcinoma in Australia: An expert commentary.

Merkel cell carcinoma (MCC) is a highly aggressive neuroendocrine tumor of the skin with an estimated disease-associated mortality of 15-33%. Australia has a higher incidence of MCC compared to the rest of the world, thought to be due to a higher ultraviolet index. The Australian MCC population is distinct from the MCC population of the Northern hemisphere, characterized by a predominantly viral negative etiology with high tumor mutational burden. The optimal management of MCC and the choice of treatment modality vary significantly across the world and even between institutions within Australia. Historically, the treatment for MCC has been resection followed by radiotherapy (RT), though definitive RT is an alternative treatment used commonly in Australia. The arrival of immune checkpoint inhibitors and the mounting evidence that MCC is a highly immunogenic disease is transforming the treatment landscape for MCC. Australia is playing a key role in the further development of treatment options for MCC with two upcoming Australian/New Zealand investigator-initiated clinical trials that will explore the interplay of RT and immunotherapy in the treatment of early and late stage MCC.

Long-term Follow-up of Standard-Dose Pembrolizumab Plus Reduced-Dose Ipilimumab in Patients with Advanced Melanoma: KEYNOTE-029 Part 1B.

PURPOSE: Combination therapy with reduced-dose programmed death 1 inhibitor plus standard-dose cytotoxic T-lymphocyte-associated antigen 4 inhibitor demonstrated efficacy, but substantial toxicity, in melanoma. We present long-term results of part 1B of KEYNOTE-029, which assessed safety and efficacy of standard-dose pembrolizumab plus reduced-dose ipilimumab in advanced melanoma. PATIENTS AND METHODS: Part 1B was an expansion cohort of the open-label, phase Ib portion of KEYNOTE-029. Eligible patients had advanced melanoma and no previous immune checkpoint inhibitor therapy. Patients received pembrolizumab 2 mg/kg (amended to 200 mg) every 3 weeks plus ipilimumab 1 mg/kg every 3 weeks (four cycles), then pembrolizumab alone for up to 2 years. Primary end point was safety; secondary end points included objective response rate (ORR), progression-free survival (PFS), duration of response (DOR), and overall survival (OS). RESULTS: A total of 153 patients received at least one dose of pembrolizumab plus ipilimumab. At a median follow-up of 36.8 months, 71.9% had received four doses of ipilimumab and 30.7% had completed 2 years of pembrolizumab; 26.1% completed both treatments. Treatment-related adverse events occurred in 96.1% (47.1% grade 3/4; no deaths), leading to discontinuation of one or both study drugs in 35.9%. ORR was 62.1% with 42 (27.5%) complete and 53 (34.6%) partial responses. Median DOR was not reached; 36-month ongoing response rate was 84.2%. Median PFS and OS were not reached; 36-month rates were 59.1% and 73.4%, respectively. CONCLUSIONS: Standard-dose pembrolizumab plus reduced-dose ipilimumab demonstrated robust antitumor activity, durable response, and favorable long-term survival with manageable toxicity.

Why pathologists and oncologists should know about tumour-infiltrating lymphocytes (TILs) in triple-negative breast cancer: an Australian experience of 139 cases.

The presence of increased tumour infiltrating lymphocytes (TILs) is established as a positive prognostic factor in triple-negative breast cancer (TNBC). The majority of studies have examined the role of TILs in predicting response to chemotherapy, but their role as a general prognostic marker in TNBC is unclear. Moreover, there is a lack of consensus in the literature regarding a suitable cut-off point by which to stratify patients into prognostic groups. Therefore, we sought to confirm the prognostic value of TILs in an independent cohort of unselected TNBCs, and to determine an appropriate cut-off point by which to stratify TIL scores into prognostically significant categories. We used the International TILs Working Group (ITWG) methodology to assess the density of stromal TILs in our cohort of 139 TNBC patients undergoing curative resection at our institution. The percentage TILs scores were categorised first into three groups: low (0-10%), intermediate (15-50%), and high (55-100%). A second binary variable was also created by separating cases into low TILs (≤50%) and high TILs (>50%) groups. Using the three-tiered system, mean disease-free survival was 156, 99 and 94 months for the high, intermediate and low TILs groups, respectively (p=0.030). However, no statistically significant improvement was observed for overall survival. Using the two-tiered system, statistically significant improvements in both overall survival (p=0.030) and disease-free survival (p=0.010) were observed. This survival benefit remained statistically significant in multivariate analyses (p=0.010, p=0.014). We conclude that TILs scored using the ITWG system and dichotomised at a cut-off score of 50%, are a powerful predictor of all-cause and disease-free survival in TNBC regardless of chemotherapy treatment.