Artificial intelligence in a prediction model for postendoscopic retrograde cholangiopancreatography pancreatitis

OBJECTIVES

In this study we aimed to develop an artificial intelligence-based model for predicting postendoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP).

METHODS

We retrospectively reviewed ERCP patients at Nagoya University Hospital (NUH) and Toyota Memorial Hospital (TMH). We constructed two prediction models, a random forest (RF), one of the machine-learning algorithms, and a logistic regression (LR) model. First, we selected features of each model from 40 possible features. Then the models were trained and validated using three fold cross-validation in the NUH cohort and tested in the TMH cohort. The area under the receiver operating characteristic curve (AUROC) was used to assess model performance. Finally, using the output parameters of the RF model, we classified the patients into low-, medium-, and high-risk groups.

RESULTS

A total of 615 patients at NUH and 544 patients at TMH were enrolled. Ten features were selected for the RF model, including albumin, creatinine, biliary tract cancer, pancreatic cancer, bile duct stone, total procedure time, pancreatic duct injection, pancreatic guidewire-assisted technique without a pancreatic stent, intraductal ultrasonography, and bile duct biopsy. In the three fold cross-validation, the RF model showed better predictive ability than the LR model (AUROC 0.821 vs. 0.660). In the test, the RF model also showed better performance (AUROC 0.770 vs. 0.663, P = 0.002). Based on the RF model, we classified the patients according to the incidence of PEP (2.9%, 10.0%, and 23.9%).

CONCLUSION

We developed an RF model. Machine-learning algorithms could be powerful tools to develop accurate prediction models.

Prevalence and Severity of Positional Posterior Plagiocephaly and Positional Posterior Brachycephaly in Children and Adolescents in Japan

This study aimed to assess the prevalence, severity, and natural history of positional posterior plagiocephaly (PPP) and positional posterior brachycephaly in Japan. We conducted a cross-sectional study of pediatric patients, ranging from 0 to 15 years old, evaluated for head trauma with negative computed tomography (CT) findings. The cranial vault asymmetry index (CVAI) was calculated using CT images at the superior orbital rim. Asymmetry according to CVAI values was subcategorized as follows: mild (3.5%-7%), moderate (7%-12%), and severe (>12%). The results were analyzed according to different age groups: group 1, 2-23 months (54 patients); group 2, 2-6 years (123 patients); and group 3, 7-15 years (123 patients). Overall, 300 patients were included (109 [36.3%] girls and 191 [63.7%] boys). The overall prevalence of PPP in the 300 patients was 46.7% (140 patients). PPP prevalence decreased consistently with age group: group 1, 57.4%; group 2, 47.2%; and group 3, 41.5%. Severe asymmetry was seen in all age groups. The overall mean cephalic index (CI) was 85.2. Cephalic index scores decreased consistently with age: group 1, 87.4; group 2, 85.1; and group 3, 84.3. The prevalence of PPP in Japan was higher than that reported in other countries. Although there was an overall decrease in the prevalence and severity of PPP with increasing patient age, PPP does not necessarily resolve spontaneously in all children. Furthermore, severe asymmetry was seen across all age groups.

Duraplasty using a combination of a pedicled dural flap and collagen matrix in posterior fossa decompression for pediatric Chiari malformation type 1 with syrinx

PURPOSE

In posterior fossa decompression for pediatric Chiari malformation type 1 (CM-1), duraplasty methods using various dural substitutes have been reported to improve surgical outcomes and minimize postoperative complications. To obtain sufficient posterior fossa decompression without cerebrospinal fluid-related complications, we developed a novel duraplasty technique using a combination of a pedicled dural flap and collagen matrix. The objective of this study was to describe the operative nuances of duraplasty using a combination of a pedicled dural flap and collagen matrix in posterior fossa decompression for pediatric CM-1.

METHODS

We reviewed the clinical and radiographic records of 11 consecutive pediatric patients who underwent posterior fossa decompression with duraplasty using a combination of a pedicled dural flap and collagen matrix followed by expansile cranioplasty for CM-1. The largest area of the syrinx and the size of the posterior fossa were calculated.

RESULTS

The maximum syrinx area was reduced by a mean of 68.5% ± 27.3% from preoperatively to postoperatively. Four patients (36.4%) had near-complete syrinx resolution (> 90%, grade III reduction), five (45.5%) had 50% to 90% reduction (grade II), and two (18.2%) had < 50% reduction (grade I). The posterior fossa area in the midsagittal section increased by 8.9% from preoperatively to postoperatively. There were no postoperative complications, including cerebrospinal fluid leakage, pseudomeningocele formation, or infection.

CONCLUSION

Duraplasty using a combination of a pedicled dural flap and collagen matrix in posterior fossa decompression is a promising safe and effective surgical technique for pediatric CM-1 with syrinx.

Pediatric intraparenchymal meningioma in the basal ganglia treated with gross total resection: a case report and review of the literature

INTRODUCTION

Intraparenchymal meningiomas in the basal ganglia are extremely rare, and to the best of our knowledge, only three case reports have been published to date. Owing to concerns regarding major vessels, gross total resection (GTR) is difficult to achieve; therefore, subtotal resection and radiation therapy are often chosen as treatment options. We present a pediatric case with an intraparenchymal meningioma in the left basal ganglia that was successfully treated with GTR. We also reviewed the relevant literature to discuss the pathogenesis, radiological findings, and treatment methods of this rare disease.

CASE REPORT

A 4-year-old girl presented with progressive right facial paralysis, aphasia, and right incomplete hemiplegia. Imaging revealed a mass lesion in the left basal ganglia and unilateral obstructive hydrocephalus. Neuroendoscopic septostomy, tumor biopsy, and cerebrospinal fluid reservoir placement were performed, and the initial pathological diagnosis was suspected glioma. Thus, craniotomy was performed to remove the tumor, which was white, elastic, and well-defined. Intraoperative rapid pathology revealed a meningioma. Postoperatively, the patient experienced transient worsening of the right incomplete hemiplegia, which subsequently improved. The final pathological diagnosis was a fibrous meningioma.

CONCLUSION

Surgery for intraparenchymal meningiomas in the basal ganglia is challenging owing to the proximity of major blood vessels; however, GTR may be preferable to subtotal resection, considering the possibility of recurrence. Even in cases of intraparenchymal tumors, it is important to consider meningioma as a differential diagnosis and to carefully plan the appropriate treatment.

Efficacy and safety of second-line therapy of docetaxel plus ramucirumab after first-line platinum-based chemotherapy plus immune checkpoint inhibitors in non-small cell lung cancer (SCORPION): a multicenter, open-label, single-arm, phase 2 trial

Background

Immune checkpoint inhibitors (ICI) plus platinum-based chemotherapy has been recognized as a standard first-line therapy in non-small cell lung cancer (NSCLC); however, no prospective clinical trials of docetaxel (DTX) plus ramucirumab (RAM) following first-line ICI plus platinum-based chemotherapy has been reported.

Methods

In this multicentre, open-label, single-arm, phase 2 trial, we enrolled patients with NSCLC from eight centres in Japan. Patients with metastatic NSCLC with disease progression after platinum-based chemotherapy plus ICI were eligible for the study. Patients were intravenously treated with 60 mg/m2 of DTX and 10 mg/kg of RAM on day 1 with a strong recommendation of pegfilgrastim administration on day 2 every 3 weeks. The primary end point was objective response rate (ORR) in efficacy analysis population. Safety was assessed in all patients treated at least one dose. The ORR of the null and alternative hypotheses were 10% and 30%, with α error of 0.1 and β error of 0.1. This trial is registered with the Japan Registry for Clinical Trials, jCRTs041190077.

Findings

Between 16 January, 2020, and 24 August, 2021, 33 patients (median age 66 [range 42-79] years) were enrolled. Thirteen patients (41%) had Eastern Cooperative Oncology Group performance status of 1. Twenty-five patients (78%) had an interval of <60 days after the last administration of ICI. In the efficacy analysis population (n = 32), the primary endpoint was met as 11 patients achieved partial response (PR), with ORR of 34.4% (80% CI, 23.1-47.2). Grade ≥3 anaemia and febrile neutropenia were observed in 2 (6%) and 3 (9%) patients, respectively. No treatment-related deaths and no new safety signals were observed.

Interpretation

DTX plus RAM demonstrated encouraging antitumor activity with a manageable safety profile in patients who have progressed on front-line ICIs plus platinum-based chemotherapy. The results of this trial can be a helpful reference in conducting further phase III trials of new second-line treatment options.

Funding

Eli Lilly Japan K.K.

Treatment optimization by monitoring vancomycin concentration in the serum and cerebrospinal fluid in a child with cystoperitoneal shunt-related infection caused by methicillin-resistant Staphylococcus aureus: a case report and literature review

BACKGROUND

Cerebral ventricular shunt infections caused by methicillin-resistant Staphylococcus aureus (MRSA), especially strains with elevated minimum inhibitory concentration (MIC) values, have a poor prognosis. Monitoring serum vancomycin (VCM) levels with therapeutic drug monitoring and maintaining high VCM concentrations in the cerebrospinal fluid (CSF) are critical to treatment success. However, there have been a few reports about the CSF penetration and the pharmacokinetics of VCM in children.

CASE PRESENTATION

Here, we report the case of a pediatric patient with cysto-peritoneal shunt-related meningitis caused by MRSA with an MIC of 2 μg/mL. The adequate VCM concentration was maintained by monitoring the VCM concentration in the CSF via the external ventricular drain, and frequent blood taking was avoided. VCM showed a good CSF penetration in our patient, and she was discharged without complications.

DISCUSSION

Therapeutic drug monitoring of VCM concentration in the CSF may result in successful treatment even if MRSA shows a higher MIC. Therapeutic drug monitoring of VCM concentration in the CSF may also reduce the side effects.

Second-line immunosuppressant administration for steroid-refractory immune-related adverse events in patients with lung cancer

BACKGROUND

Evidence for use of second-line immunosuppressants for immune-related adverse events (irAEs) is inadequate. Therefore, a multicenter analysis should assess the efficacy of second-line immunosuppressants for severe irAEs associated with different malignant diseases.

METHODS

This descriptive study aims to investigate the effects of second-line immunosuppressants on corticosteroid-refractory irAEs in patients with lung cancer. We analyzed the effects of second-line immunosuppressants on underlying lung cancer and associated adverse effects.

RESULTS

Our study included 4589 patients who had received immune checkpoint inhibitor treatment, with 73 patients (1.6%) developing irAEs requiring second-line immunosuppressants. The most commonly observed irAE was pneumonitis (26 patients), followed by hepatobiliary disorders (15 patients) and enteritis (14 patients). We found a confirmed response rate of 42.3% for pneumonitis, which was lower than the response rates of 86.7% for hepatobiliary disorders and 92.9% for enteritis. The time from the start of corticosteroid therapy to the addition of a second-line immunosuppressant correlated significantly with the resolution of irAE to Grade 1 (correlation coefficients of r = 0.701, p < 0.005). The median progression-free survival and duration of response of underlying lung cancer from second-line immunosuppressant administration were 2.1 and 3.0 months, respectively. Of the patients with irAE, 27.4% developed infections and 5.5% might die due to infection.

CONCLUSION

Second-line immunosuppressant response was confirmed in 72.2% of irAEs in patients with lung cancer, with lower response rates observed in irAE pneumonitis compared to other irAEs.

Metabolic barriers in non-small cell lung cancer with LKB1 and/or KEAP1 mutations for immunotherapeutic strategies

Currently, immune checkpoint inhibitors (ICIs) are widely considered the standard initial treatment for advanced non-small cell lung cancer (NSCLC) when there are no targetable driver oncogenic alternations. NSCLC tumors that have two alterations in tumor suppressor genes, such as liver kinase B1 (LKB1) and/or Kelch-like ECH-associated protein 1 (KEAP1), have been found to exhibit reduced responsiveness to these therapeutic strategies, as revealed by multiomics analyses identifying immunosuppressed phenotypes. Recent advancements in various biological approaches have gradually unveiled the molecular mechanisms underlying intrinsic reprogrammed metabolism in tumor cells, which contribute to the evasion of immune responses by the tumor. Notably, metabolic alterations in glycolysis and glutaminolysis have a significant impact on tumor aggressiveness and the remodeling of the tumor microenvironment. Since glucose and glutamine are essential for the proliferation and activation of effector T cells, heightened consumption of these nutrients by tumor cells results in immunosuppression and resistance to ICI therapies. This review provides a comprehensive summary of the clinical efficacies of current therapeutic strategies against NSCLC harboring LKB1 and/or KEAP1 mutations, along with the metabolic alterations in glycolysis and glutaminolysis observed in these cancer cells. Furthermore, ongoing trials targeting these metabolic alterations are discussed as potential approaches to overcome the extremely poor prognosis associated with this type of cancer.

Epidural Spinal Cord Compression as the Presenting Manifestation of Acute Myeloid Leukemia: A Case Report and Literature Review

We herein report a rare case of spinal cord compression due to epidural involvement of acute myeloid leukemia (AML). A 14-year-old boy presented with a 7-day history of back pain, paraplegia and hypoesthesia. Contrast-enhanced computed tomography revealed an epidural mass. Emergency laminectomy and resection of the mass were performed. Histopathologically, the resected mass was comparable to an extramedullary mass of AML. Chemotherapy was initiated, and complete remission was achieved. Neurological sequelae remained after the treatment. Based on the present and previous reports, spinal cord compression from epidural AML involvement may progress rapidly.

Endovascular Treatment of Tandem Atherosclerotic Cervical Internal Carotid Artery Occlusion in the Setting of Acute Ischemic Stroke

BACKGROUND

Among tandem occlusions, atherosclerotic cervical internal carotid artery occlusion (ACICAO) can be technically challenging and associated with its unique complications. We evaluated our experience with endovascular treatment (EVT) of ACICAO in the setting of acute ischemic stroke.

METHODS

In total, 154 consecutive patients who underwent EVT for acute anterior circulation stroke at our institute were retrospectively reviewed. Patients with tandem ACICAO were analyzed in this study. Procedures, recanalization rates, complications, and prognoses were evaluated.

RESULTS

Ten patients (6%) of all 154 patients had ACICAO. In nine (90%) of the 10 patients, cervical lesions were successfully crossed and intervened upon. Four patients underwent stenting and five underwent angioplasty alone, followed by intracranial procedure. Eight patients (80%) achieved successful recanalization following mechanical thrombectomy for intracranial occlusion. However, one patient had massive subarachnoid hemorrhage during the procedure and another patient developed massive intracranial hemorrhage after EVT, both after stenting. Four of the five patients who initially underwent angioplasty alone subsequently underwent staged endarterectomy or stenting for residual stenosis on or after the next day. The single patient in whom the cervical lesion could not be crossed and another with reocclusion after EVT underwent a rescue bypass procedure due to persistent ischemic symptoms. After 90 days, four patients (40%) were functionally independent (modified Rankin scale score 0-2).

CONCLUSIONS

Our experience suggests that EVT for ACICAO is technically feasible; however, it involves the potential risk of several significant complications. To avoid serious hemorrhagic complications, cervical lesions may be better treated with angioplasty alone first.

COT-13 OUTCOMES OF MEDULLOBLASTOMA IN KOBE CHILDREN,S HOSPITAL OVER THE RECENT 11 YEARS

Introduction

Medulloblastoma is the most frequent malignant brain tumor in children, which 5-year survival rate have improved to 70-85%. In this study, we retrospectively reviewed outcomes and late complications of 31 medulloblastoma cases treated at our institute from 2010 to 2021.

Cases

The mean age of the cases was 6.5 years. 22 cases were total resection and 17 were judged to be in the high-risk group. With respect to histopathological diagnosis, 23 cases were classified as classic type, 2 as desmoplastic/nodular type, 2 as with extensive nodularity type, and 4 as anaplastic/large cell type. As for molecular analysis, WNT was 2, SHH was 3 , Group 3 was 3, Group 4 was 8 cases. One case was lost due to relocation.

Results

21 patients have no recurrence of medulloblastoma, but two were victims of second cancers. The remaining 19 cases were all in the standard-risk group and survived with a complete reaction (CR). There were 9 cases of recurrence (including disseminated disease) and the survived case after retreatment was only one in the high-risk group which indicated CR.

Discussion

The 5-year survival rate for patients in standard-risk group at our institution was 92.3%, indicating improved outcomes. The poor prognosis group could be divided in group who developed recurrence or second cancers after 5 years or more and group who indicated insufficient reaction to multimodality treatment and died around 2 years after diagnosis. As late complications, there were 5 cases of higher functional impairment, who were 16.7% of whole cases and almost in the high-risk group. It is necessary to pursue further treatment for the high-risk group and to recognize that the number of survivors of medulloblastoma cases is increasing, and to support for the AYA generation.

COT-14 OUTCOMES OF MEDULLOBLASTOMA IN KOBE CHILDREN,S HOSPITAL OVER THE RECENT 11 YEARS

Introduction

Medulloblastoma is the most frequent malignant brain tumor in children, which 5-year survival rate have improved to 70-85%. In this study, we retrospectively reviewed outcomes and late complications of 31 medulloblastoma cases treated at our institute from 2010 to 2021.

Cases

The mean age of the cases was 6.5 years. 22 cases were total resection and 17 were judged to be in the high-risk group. With respect to histopathological diagnosis, 23 cases were classified as Classic type, 2 as Desmoplastic/nodular type, 2 as With extensive nodularity type, and 4 as Anaplastic/Large cell type. As for molecular analysis, WNT was 2, SHH was 3 , Group 3 was 3, Group 4 was 8 cases. One case was lost due to relocation.

Results

21 patients have no recurrence of medulloblastoma, but two were victims of second cancers. The remaining 19 cases were all in the standard-risk group and survived with a complete reaction (CR). There were 9 cases of recurrence (including disseminated disease) and the survived case after retreatment was only one in the high-risk group which indicated CR.

Discussion

The 5-year survival rate for patients in standard-risk group at our institution was 92.3%, indicating improved outcomes. The poor prognosis group could be divided in group who developed recurrence or second cancers after 5 years or more and group who indicated insufficient reaction to multimodality treatment and died around 2 years after diagnosis. As late complications, there were 5 cases of higher functional impairment, who were 16.7% of whole cases and almost in the high-risk group. It is necessary to pursue further treatment for the high-risk group and to recognize that the number of survivors of medulloblastoma cases is increasing, and to support for the AYA generation.

Clinical efficacy of amrubicin in patients with small cell lung cancer relapse after first-line treatment including immune checkpoint inhibitors: A retrospective multicenter study (TOPGAN 2021-01)

BACKGROUND

The therapeutic efficacy of cytotoxic anticancer drugs has been reported to be enhanced after immune checkpoint inhibitors (ICI) in non-small cell lung cancer; however, it is unclear whether the same is applicable for small cell lung cancer (SCLC). We evaluated the efficacy of second-line amrubicin (AMR) following first-line platinum-based chemotherapy and ICI combination therapy (chemo-ICI) in SCLC.

PATIENTS AND METHODS

We retrospectively enrolled consecutive patients with SCLC treated with AMR as a second-line following chemo-ICI as first-line between July 2019 and April 2021 from 16 institutions throughout Japan. We investigated the therapeutic effectiveness, safety, and efficacy-enhancing variables of AMR.

RESULTS

Overall, 89 patients treated with AMR after first-line chemo-ICI were analyzed. The overall response rate (ORR) was 29.2% (95% confidence intervals [CI], 20.1-39.8) and median PFS (m PFS) was 2.99 months (95% CI, 2.27-3.65). Patients who relapsed more than 90 days after receiving first-line platinum combination therapy (sensitive relapse) exhibited greater ORR (58.3% vs. 24.7%, p = 0.035) and m PFS (5.03 vs. 2.56 months, p = 0.019) than patients who relapsed in <90 days (refractory relapse). Grade 3 or higher adverse events were mainly hematological toxicity.

CONCLUSIONS

Our study suggested that the therapeutic effect of AMR was not enhanced after ICI on SCLC. However, AMR may be effective in cases of sensitive relapse after chemo-ICI. There was no increase in severe toxicity associated with AMR after ICI.

Non-invasive early prediction of immune checkpoint inhibitor efficacy in non-small-cell lung cancer patients using on-treatment serum CRP and NLR

PURPOSE

We determined the clinical relevance of early C-reactive protein (CRP) and neutrophil-lymphocyte ratio (NLR) change in blood as surrogate markers of pro-tumor inflammation (PTI) for predicting clinical outcome of programmed cell death (PD)-1/programmed cell death ligand (PD-L) 1 inhibitor treatment in non-small-cell lung carcinoma (NSCLC).

METHODS

We retrospectively reviewed NSCLC patients treated with anti-PD-1 or PD-L1 inhibitors. Early CRP change was defined as the ratio of 6 weeks CRP to baseline CRP, and early NLR change was defined as that of the 6 weeks NLR to baseline NLR. PTI index was determined by combinatorial evaluation of early CRP change and early NLR change, PTI index low: both of these were low, intermediate: either of these was low, high; both of these were high.

RESULTS

The study included 217 patients. Early CRP change and early NLR change were both associated with PFS and OS. The combinatorial evaluation using these two markers enabled the clear stratification of PFS and OS. The median PFS in patient with PTI index low was 13.9 months, while the median PFS in those with PTI index high was 2.5 months (p < 0.01, log-rank test). The median OS in patients with PTI index low was not reached; the median OS in those with PTI index high was only 15.4 months (p < 0.01, log-rank test).

CONCLUSIONS

The combinatorial early CRP change and early NLR change as PTI biomarkers have clinical potential in identifying NSCLC patients who can achieve a durable response and long-term survival using PD-1/PD-L1 inhibitors.

Repair of refractory postoperative cerebrospinal fluid leakage using a reversed dermis flap in a pediatric lipomyelomeningocele patient

INTRODUCTION

Cerebrospinal fluid (CSF) leak and pseudomeningocele are common complications after surgery for spinal dysraphism.

CASE REPORT AND TECHNIQUE

We report a 6-month-old girl with a lumbosacral lipomyelomeningocele and accessory lower limb who developed a refractory cerebrospinal fluid leak and pseudomeningocele after lipomyelomeningocele repair and removal of the accessory limb. The pseudomeningocele was successfully repaired using a reversed dermis flap made from excess skin that covered the meningocele.

CONCLUSION

This technique can be performed without using synthetic material or an additional surgical incision.

Amelanotic Malignant Melanoma with a BRAF V600E Mutation Mimicking Primary Lung Cancer

Amelanotic melanoma is a rare type of melanoma that shows little or no melanin pigmentation. When tumor lesions are not detected in cutaneous sites, the presence of melanin is the hallmark sign of malignant melanoma. We herein report a case of amelanotic melanoma with a BRAF V600E mutation mimicking primary lung cancer that was finally diagnosed on an autopsy. The current case suggests important caveats for the differential diagnosis of patients with BRAF V600E mutation-positive poorly differentiated lung tumors. In terms of the pathological diagnosis, routine immunohistochemical staining may be useful, especially in patients with a poorly differentiated lung tumor without TTF-1 expression.

BT-4 The treatment history of long-term survivors of Optic Pathway Glioma in Kobe Children’s Hospital

Optic pathway glioma(OPG) is almost recognized in childhood and about 0.01–0.02% of whole brain tumor in Japan. Because of the rare tumor, there are few reports about results of its treatment. In 2021, Guideline of Optic pathway/hypothalamic glioma is indicated from The japan Society for Neuro-Oncology. We retrospectively study 9 cases history of OPG who have treated for more than 5 years from January 2005 to March 2021 in Kobe Children’s Hospital. Cases are 4 boys and 5 girls. Average age at diagnosis is 3.8 years old and average follow up term is 11 years 10 months. They are 4 Pilocytic astrocytoma, 3 Pilomyxoid astrocytoma, and 1 Fibrillary astrocytoma. Al l cases have survived. There are only 2 cases who could be controlled with single series of surgical treatment and chemotherapy. Most cases need several times of resection and chemotherapy and uncontrollable 5 cases required radiological treatment. 2 cases are still under treatment for over 10 years. For OPG, partial resection to control hydrocephalus is recommended and several trial of chemotherapy must be carried out. There exist a few cases who need continuous treatment for long term. The other side, a few cases are uncontrollable those need radiotherapy to manage tumor volume. Because the history of OPG would be long term, we should adjust the treatment plan to environment of patients.

A phase I/II study of osimertinib in EGFR exon 20 insertion mutation-positive non-small cell lung cancer

OBJECTIVES

Several preclinical data proposed a potential efficacy of osimertinib, a third-generation EGFR tyrosine kinase inhibitor, for EGFR exon 20 insertion (EGFR ex20ins)-positive non-small cell lung cancer (NSCLC). However, reported case series and a retrospective study proposed controversial efficacy. The efficacy of osimertinib in EGFR ex20ins-positive NSCLC have not been well evaluated in prospective clinical trials. In this study, we performed a prospective, single-arm, multi-center, open-label, non-randomized phase I/II study to evaluate efficacy of osimertinib for EGFR ex20ins-positive NSCLC.

MATERIALS AND METHODS

From August 2018 to January 2020, 14 NSCLC patients with EGFR ex20ins were enrolled, of whom 2 were excluded because they did not meet the inclusion criteria. Efficacy and safety of 80 mg osimertinib were evaluated. In addition, we performed a translational exploratory study to clarify the association of mutation type-specific drug sensitivity, osimertinib pharmacokinetic data, and clinical efficacy.

RESULTS

Of the evaluated patients, none experienced objective response, 7 experienced stable disease (58.3%), and 5 experienced disease progression (41.7%). The median progression free survival (PFS) was 3.8 months, and the median overall survival was 15.8 months. Interestingly, the exploratory study demonstrated statistically significant positive correlation between plasma osimertinib concentration/in vitro IC₅₀ ratio and PFS (R = 0.9912, P = 0.0001), highlighting the mutation type-specific concentration-dependent efficacy of osimertinib for EGFR ex20ins-positive NSCLC.

CONCLUSIONS

Regular dose, 80 mg/day, of osimertinib has limited clinical activity in NSCLC patients with EGFR ex20ins. The translational study proposed the potential efficacy of higher dose osimertinib in a subgroup of EGFR ex20ins-positive NSCLC.

Is area under the curve the best parameter for carboplatin induced emetic risk stratification?

Carboplatin (CBDCA)-induced emetic risk is currently classified on the basis of CBDCA-area under the curve (CBDCA-AUC). We investigated the utility of three CBDCA dosage parameters for predicting emesis by CBDCA. Patients with thoracic cancer treated with CBDCA were included. The endpoints were complete response (CR) and total control (TC). CR was defined as no vomiting and no use of rescue medication during the overall assessment period, whereas TC was defined as no vomiting, nausea, nor use of rescue medication during the overall assessment period. The parameters of CBDCA were defined as follows: (1) CBDCA-AUC; (2) CBDCA/body surface area (BSA): the administered dose of CBDCA per body surface area (mg/m²); and (3) total CBDCA/body: the total administered dose of CBDCA (mg). Eighty-five patients were evaluated. The median CBDCA/BSA but not CBDCA-AUC was higher in patients with non-CR compared to those with CR. Receiver operating characteristic curve analysis revealed that the AUC of CBDCA/BSA for predicting non-CR was higher than that of CBDCA-AUC. CBDCA/BSA shows greater potential for predicting CBDCA-induced emetic risk compared with CBDCA-AUC, which is the parameter in current antiemetic guidelines.

RONC-01. PROTON BEAM THERAPY IN THE MULTIDISCIPLINARY THERAPY FOR PEDIATRIC BRAIN AND SPINAL TUMOR AT KOBE CHILDREN’S HOSPITAL WITH KOBE PROTON CENTER

It could be remarked that Radiotherapy (RT) has the important role for the multidisciplinary therapy to Malignant Pediatric Central Nervous System tumor. And recently among RT, Proton Beam Therapy (PBT) is expected to be effective and decrease serious late effects after RT in malignant pediatric tumor. PBT could be controlled precisely the dose and depth and spare the normal structures outside the target. Thus, PBT becomes applicable for pediatric solid tumor to insurance in April, 2016 in Japan. We have worked in closer cooperation with Hyogo Prefectural Ion Beam Medical Center and started PBT from April 2015. And from December 2017, our PBT has transferred to adjacent new medical center (Kobe Proton Center) which has the only institute that equipped the exclusive gantry for children in our country. The treated cases are 28 boys and 35 girls (age average 8.2 years oid). They are 15 Germ cell tumor, 14 Ependymoma, 13 Medulloblastoma, 4 Chordoma, 4 Atypical teratoid/rhabdoid tumor, 2 Craniopharyngioma and others. We have simulated the applications of not only broad beam but also scanned beam to limit the dose distribution and prepare for the cranio-spinal irradiation. All cases underwent magnetic resonance imaging to evaluate the results at out clinic and also the complications are assessed after treatments. The effect of PBT in this series is similar to our experience of traditional RT. There are a few controllable complications such as conventional RT. Farther more follow up is necessary to evaluate the advantage of PBT which could reduce delayed complications of RT.

Primary Prophylaxis Indication for Docetaxel Induced Febrile Neutropenia in Elderly Patients with Non-Small Cell Lung Cancer

In advanced non-small cell lung cancer (NSCLC), the reported incidence of febrile neutropenia (FN) caused by docetaxel (DTX) is 10-20% in clinical trial data. However, FN incidence caused by DTX in real-world setting remains unclear. We evaluated FN incidence caused by DTX and identify risk factors of FN in real-world setting. One hundred and seventy-one NSCLC patients treated with DTX were retrospectively analyzed and 44 (26%) developed FN. Multivariate analysis identified higher age (≥65 years) and prior history of FN as independent risk factors for FN. Primary prophylaxis for FN might be recommended in elderly patients with/without prior history of FN.

Management and problems of prolonged survival with hydranencephaly in the modern treatment era

PURPOSE

Hydranencephaly is a rare condition that occurs during embryogenesis after neurogenesis and is characterized by the near complete absence of the cerebral hemispheres. In general, patients with hydranencephaly have been considered to have a markedly reduced life expectancy. We present 4 patients with hydranencephaly who have survived for over 5 years. The management and problems encountered in these cases are discussed.

METHODS

A retrospective review was conducted at our institution. Medical charts and radiographic studies were reviewed. Data including age at follow-up, sex, clinical complications, and surgical procedures were recorded.

RESULTS

Six patients were radiologically diagnosed with hydranencephaly during the period from January 2000 to December 2012. Two patients were excluded from our study: one because of death from pneumonia at 1 year of age and another because of transfer to another hospital. Four patients (3 males and 1 female) were included in the analysis. All 4 patients underwent ventriculoperitoneal shunt (VPS) placement and shunt revision. VPS infection occurred in 3 of 4 cases, and bloody cerebrospinal fluid (CSF) was observed in 2 of 4 cases. One patient underwent successful choroid plexus cauterization (CPC) and shunt removal after shunt infection.

CONCLUSIONS

Prolonged survival with hydranencephaly is not unusual in the modern treatment era. CSF shunt problems, such as recurring shunt malfunction and shunt infection, represent one of the major problems, and avoiding CSF shunt with CPC is particularly desirable in patients with hydranencephaly.

Impact of introducing endovascular treatment on acute ischemic stroke outcomes: A shift from an era of medical management to thrombectomy in Japan

Background

Endovascular treatment (EVT) has increasingly become the standard treatment of acute cerebral large vessel occlusion (LVO). We evaluated the impact of introducing EVT on LVO therapy in a single center where intravenous thrombolysis (IVT) had been the only recanalization therapy.

Materials and methods

Between April 2013 and March 2017, 354 consecutive patients with LVO admitted to our institution were analyzed. We compared outcomes between two chronological groups before (Pre-EVT group) and after (Post-EVT group) introducing EVT in April 2015. We assessed prognostic factors for favorable outcomes (modified Rankin scale score ≤2 at 90 days).

Results

In the Pre-EVT group, all 140 patients were treated medically, including 30 patients (21%) undergoing IVT. In the Post-EVT group, 118 patients (55%) underwent EVT, and the remaining 96 patients treated medically, including six patients (3%) undergoing IVT. The proportion undergoing recanalization therapy with IVT or EVT significantly increased after introducing EVT (21% versus 58%, p < 0.001). The rate of patients achieving favorable outcomes also significantly increased (14% versus 31%, p < 0.001). In multivariate regression analysis, introducing EVT was an independent predictive factor after adjusting for age, stroke severity and extent, and time (p = 0.005). The arrival time in patients with helicopter transport was significantly shorter than that with ground ambulance for a distance of more than 10 km (p < 0.001).

Conclusions

This study demonstrated that the introduction of EVT improved outcomes of acute LVO patients, increasing the opportunity to receive recanalization therapy. Further efforts to establish medical systems to provide EVT are required throughout the country.

P29 Arrest of progression of cardiac amyloidosis after chemotherapy predicts favorable outcome in patients with light-chain amyloidosis

Funding Acknowledgements

none

Background

Many studies demonstrated that cardiac involvement predicts poor prognosis in patients with systemic light-chain amyloidosis (AL). There is no data about the effect of the arrest of progression of cardiac amyloidosis on prognosis after chemotherapy.

Hypothesis

Arrest of progression of cardiac amyloidosis is associated with favorable outcome in patients with light-chain amyloidosis.

Methods

Among 126 consecutive patients with AL, we prospectively examined 94 patients serially after optimal therapy. The mean follow-up period was 1405 ± 1510 days (median value 734 days, inter quartile range 176-2343 days). Wall thickness was measured from left ventricular (LV) m-mode trace. We defined the cardiac involvement as mean LV wall thickness &gt;12mm, and the regression or progression of cardiac amyloidosis as change in LV mean wall thickness &gt;1mm.

Results

Among 94 patients with AL, 28 patients (30%) showed regression by definition above, 35 patients (37%) showed no interval change and 31 patients (33%) showed progression of cardiac amyloidosis. Survival analysis of 3 groups demonstrated that the regression and arrest of progression groups showed better outcome compared with the progression group (Log-rank test P &lt; 0.0001).

Conclusions

The arrest of progression of cardiac amyloidosis predicts favorable outcome in patients with AL amyloidosis.

Abstract P29 Figure. Kaplan-Meier Curve of 3 groups

NQPC-09 PROGNOSIS AND DELAYED COMPLICATIONS OF MEDULLOBLASTOMA IN KOBE CHILDREN’S HOSPITAL

Medulloblastoma is the most common pediatric malignant tumor and about 84.2% of cases are under 15 years old. With a current combined-modality approach that includes surgical approach, chemotherapy and radiation therapy, 5 year-survival rates have become 70–85% and also the so-called long-term survivors have increased in our country. This report reviews the prognosis and delayed complications of medulloblastoma in our institute. Cases were 14 boys and 11 girls from January,2010 to May 2019. Mean age was 6.1 years old (4 months to 14 years old). 18 cases receiver gross total removal and 12 cases were high risk group. Exclude recent 4 cases, 15 cases have indicated complete reaction though 6 cases had relapsed or new tumor. The results are that 5 year-survival rates in our institute is 86.7%, but 4 cases had neuro-psychological complications. 5 cases suffered from endocrinal disorders which were not confirmed after the end of all treatments. 2 secondary cancer had appeared 5 and 8 years after the first treatments. The more the survivor in medulloblastoma cases increase, neurosurgeons have to consider long term follow up more than 5 years and pay more attention to support activity of daily life of these patients.

Barcode sequencing identifies resistant mechanisms to epidermal growth factor receptor inhibitors in circulating tumor DNA of lung cancer patients

Most patients with epidermal growth factor receptor (EGFR) mutation‐positive non‐small cell lung cancer (NSCLC) will inevitably develop acquired resistance induced by treatment with EGFR tyrosine kinase inhibitors (EGFR‐TKI). The mechanisms of resistance to EGFR‐TKI are multifactorial, and the detection of these mechanisms is critical for treatment choices in patients who have progressed after EGFR‐TKI therapy. We evaluated the feasibility of a molecular barcode method using next‐generation sequencing to detect multifactorial resistance mechanisms in circulating tumor DNA and compared the results with those obtained using other technologies. Plasma samples were collected from 25 EGFR mutation‐positive NSCLC patients after the development of EGFR‐TKI resistance. Somatic mutation profiles of these samples were assessed using two methods of next‐generation sequencing and droplet digital PCR (ddPCR). The positive rate for EGFR‐sensitizing mutations was 18/25 (72.0%) using ddPCR, 17/25 (68.0%) using amplicon sequencing, and 19/25 (76.0%) using molecular barcode sequencing. Rate of the EGFR T790M resistance mutation among patients with EGFR‐sensitizing mutations was shown to be 7/18 (38.9%) using ddPCR, 6/17 (35.3%) using amplicon sequencing, and 8/19 (42.1%) using molecular barcode sequencing. Copy number gain in the MET gene was detected in three cases using ddPCR. PIK3CA,KRAS and TP53 mutations were detected using amplicon sequencing. Molecular barcode sequencing detected PIK3CA,TP53,KRAS, and MAP2K1 mutations. Results of the three assays were comparable; however, in cell‐free DNA, molecular barcode sequencing detected mutations causing multifactorial resistance more sensitively than did the other assays.

Correlation between serum adenosine deaminase activity and efficacy of anti-programmed cell death-1 antibody

OBJECTIVE

Serum adenosine deaminase (ADA) activity is a marker of immune reaction to several diseases. We evaluated changes in serum ADA in patients with lung cancer undergoing chemotherapy or anti-programmed cell death-1 (PD-1) therapy to examine the correlation between serum ADA and the therapy efficacy.

MATERIALS AND METHODS

We assessed 50 patients with advanced lung cancer receiving chemotherapy or anti-PD-1 therapy. Serum ADA was measured before and on day 7 of the first treatment cycle and day 0 of subsequent cycles. Correlations between ADA change and efficacy of treatment were evaluated.

RESULTS

Of the 50 patients, 20 were treated with chemotherapy and 30 were treated with anti-PD-1 therapy. Serum ADA decreased significantly between baseline and day 7 of the first cycle in patients undergoing chemotherapy, regardless of response (partial response [PR] or stable disease [SD]: -23% [-38 to +32; p =  0.002]; progressive disease [PD]: -12% [-42 to +6; p =  0.500]). Conversely, in patients undergoing anti-PD-1 therapy, serum ADA increased significantly between baseline and 7 days after the first dose and before subsequent doses in patients who had PR or SD. (day 7 of first cycle: +6% [-10 to +34; p =  0.034], day 0 of second cycle: 8% [-5 to +37; p =  0.002], day 0 of third cycle: 9% [-3 to +55; p =  0.002]). However, serum ADA did not significant change in PD patients undergoing anti-PD-1 therapy. Furthermore, early increases in serum ADA were associated with longer progression-free survival in patients receiving anti-PD-1 therapy (p =  0.006).

CONCLUSION

Changes in serum ADA could be used to predict clinical benefit from anti-PD-1 therapy in patients with lung cancer. The association between changes in serum ADA and the efficacy of ant-PD-1 therapy thus remains inconclusive and requires further study.

Correlation between thyroid transcription factor-1 expression, immune-related thyroid dysfunction, and efficacy of anti-programmed cell death protein-1 treatment in non-small cell lung cancer

Background

Recent studies have suggested a correlation between immune-related thyroid dysfunction (irTD) and the superior efficacy of anti-programmed cell death protein-1 (anti-PD-1) treatment in non-small cell lung cancer (NSCLC). Embryologically, the lung and thyroid are similar in origin, and thyroid transcription factor-1 (TTF-1) expresses in both organs, including NSCLC. We explored our hypothesis that TTF-1 expression in NSCLC might correlate with irTD incidence and anti-PD-1 treatment efficacy.

Methods

We identified 132 patients with NSCLC treated with anti-PD-1 antibody at our hospital between December 2015 and June 2017. We evaluated TTF-1 expression in tumor by immunohistochemistry using a mouse monoclonal antibody (clone 8G7G3/1, 1:100, Dako). IrTD was defined as two or more successive abnormal levels of thyroid-stimulating hormone (TSH) during anti-PD-1 treatment. We retrospectively assessed correlations between TTF-1 expression in tumor, irTD incidence, and anti-PD-1 treatment efficacy.

Results

Of 132 patients, 67 (51%) and 65 (49%) were positive and negative for TTF-1, respectively. We observed irTD in 19 patients (6 positives and 13 negatives for TTF-1). The incidence of irTD was 9% and 20% in TTF-1-positive and TTF-1-negative NSCLCs, respectively (P=0.086). Particularly, in non-squamous (NSQ) cell carcinomas, the irTD incidence was significantly higher in patients negative for TTF-1 (30%) than in those positive for TTF-1 (9%; P=0.010), and TTF-1 expression was identified as a significant risk factor for irTD on multivariate logistic regression analysis [odds ratio (OR), 0.18; 95% confidence interval (CI), 0.05-0.59; P=0.005]. Furthermore, longer median progression-free survival (10.3 months) was observed in patients with TTF-1-negative NSCLC with irTD compared to those with TTF-1-positive NSCLC with irTD, TTF-1-positive NSCLC without irTD, and TTF-1-negative NSCLC without irTD (4.2, 1.4, and 2.4 months, respectively).

Conclusions

TTF-1 expression in NSCLC might correlate with irTD and anti-PD-1 treatment efficacy.

Spontaneous spinal epidural hematoma mimicking Guillain-Barre Syndrome

BACKGROUND

The initial symptoms of Guillain-Barre Syndrome (GBS) can be similar to a case of spontaneous spinal epidural hematoma (SSEH) located at the cervicothoracic junction. Therefore, SSEH may be misdiagnosed as GBS.

CASE REPORT

A previously healthy 6-year-old girl presented with a 2-day history of progressive pain in the lower extremities and an inability to walk. On initial evaluation, she was completely paraparetic in the lower extremities. Deep tendon reflexes were absent in the lower extremities, and Babinski reflexes were positive on both sides. She exhibited reduced response to light touch and pinprick with a sensory level below T10, and experienced difficulty during urination. However, the strength, sensation and flexion of upper extremities were normal. Because her presentation and examinations were consistent with GBS, we initiated intravenous immunoglobulin therapy. The next day, she also developed pain and muscle weakness of the right upper extremity. Three days after admission, respiratory depression progressed rapidly. Spinal MRI showed a mass extending from the level of C7-T3, with spinal cord compression. The patient underwent an emergency laminectomy with evacuation of hematoma, and was diagnosed with SSEH. Sixty days after admission, she was transferred to the rehabilitation hospital with severe neurologic sequelae of paralysis in both legs.

CONCLUSION

SSEH might have severe consequences, including neurologic deficits and risk of death. This case report serves to raise the awareness of SSEH that mimics the initial presentation of GBS.

Characterization of Computed Tomography Imaging of Rearranged During Transfection-rearranged Lung Cancer

BACKGROUND

Rearranged during transfection (RET)-rearranged non-small-cell lung cancer (NSCLC) is relatively rare and the clinical and computed tomography (CT) image characteristics of patients with an advanced disease stage have not been well documented.

PATIENTS AND METHODS

We identified patients with advanced-stage RET-rearranged NSCLC treated in the Cancer Institute Hospital, Japanese Foundation for Cancer Research, and analyzed the clinical and CT imaging characteristics.

RESULTS

In 21 patients with advanced RET-rearranged NSCLC, RET rearrangements were identified using fluorescence in situ hybridization and/or reverse transcriptase-polymerase chain reaction. The fusion partner genes were identified as KIF5B (57%), CCDC6 (19%), and unknown (24%). CT imaging showed that 12 primary lesions (92%) were peripherally located and all were solid tumors without ground-glass, air bronchograms, or cavitation. The median size of the primary lesions was 30 mm (range, 12-63 mm). Of the 18 patients with CT images before initial chemotherapy, 12 (67%) showed an absence of lymphadenopathy. Distant metastasis included 13 with pleural dissemination (72%), 10 with lung metastasis (56%), 8 with bone metastasis (44%), and 2 with brain metastasis (11%).

CONCLUSION

Advanced RET-rearranged NSCLC manifested as a relatively small and peripherally located solid primary lesion with or without small solitary lymphadenopathy. Pleural dissemination was frequently observed.

Dramatic response to alectinib in inflammatory myofibroblastic tumor with anaplastic lymphoma kinase fusion gene

Inflammatory myofibroblastic tumor (IMT) is a neoplasm characterized by the proliferaton of myofibroblasts with the infiltration of inflammatory cells. There is no standard treatment for patients with recurrent or metastatic IMT. We describe here a patient with hyper-progressive IMT with an anaplastic lymphoma kinase (ALK) fusion gene that dramatically responded to alectinib without adverse events. His dramatic and enduring response supports the observation that alectinib may be considered a good treatment option for rare aggressive ALK-positive tumors.

EGFR T790M mutation after chemotherapy for small cell lung cancer transformation of EGFR-positive non-small cell lung cancer

In non-small cell lung cancer (NSCLC) with an epidermal growth factor receptor (EGFR) mutation, 50%–65% of cases acquire resistance after treatment with EGFR-tyrosine kinase inhibitors (EGFR-TKIs) because of an EGFR T790M point mutation and 3%–14% of these cases transformed to small cell lung cancer (SCLC). Generally, the EGFR T790M secondary mutation develops with ongoing ATP competitive inhibition. We present a case of a 76-year-old woman with lung adenocarcinoma harboring an EGFR-L858R mutation who received first-line gefitinib and developed SCLC transformation. She was administered several chemotherapy agents, including a platinum doublet. The primary lesion that showed SCLC transformation had reconverted to adenocarcinoma with EGFR L858R and T790M mutations at the time of a second re-biopsy. Therefore, she was administered osimertinib, which resulted in clinical remission. This case suggested that serial biopsies are necessary even after SCLC transformation.

High ratio of T790M to EGFR activating mutations correlate with the osimertinib response in non-small-cell lung cancer

OBJECTIVES

Osimertinib is a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor that can overcome resistance due to the Thr790Met (T790M) mutation. However, osimertinib occasionally shows limited efficacy in a small population of patients. We investigated the correlation between the ratio of T790M to EGFR activating mutation and the response to osimertinib.

MATERIALS AND METHODS

Between April 2016 and April 2017, 44 patients started osimertinib therapy at the Cancer Institute Hospital of the Japanese Foundation for Cancer Research. We performed EGFR mutation analysis of cytological samples from 33 patients using droplet digital PCR. We calculated the ratio of T790M to EGFR activating mutations and correlated it with the systemic response to osimertinib.

RESULTS

In tumors from the 33 patients, the average ratio of T790M to EGFR activating mutations was 0.420. Twenty-one of the 33 patients had tumors with a T790M ratio of ≥0.4. The osimertinib response rate was significantly higher (92.3%) in patients with a T790M ratio of ≥0.4 than in those with a T790M ratio of <0.4 (52.6%; p = 0.0237). We examined the correlation between the T790M ratio and the tumor reduction rate and obtained a coefficient of r = 0.417 (p = 0.0175). In patients with a T790M ratio of ≥0.4, the median progression-free survival was 355 days, which was longer, but not significant, than that in patients with a T790M ratio of <0.4 (median: 264 days). In patients with a T790M ratio of ≥0.4, the median treatment duration from first-line therapy onward was 931 days, which was significantly longer than that in patients with a T790M ratio of <0.4 (median, 567.5 days) (p = 0.044).

CONCLUSION

The T790M ratio to EGFR activating mutation in tumor may correlate with the response to osimertinib, and patients with a higher T790M ratio have a longer treatment history.

Adrenal Insufficiency Related to Anti-Programmed Death-1 Therapy

BACKGROUND/AIM

Adrenal insufficiency is one of the adverse events (AEs) associated with anti-programmed death-1 (PD1) therapy. Delaying diagnoses can lead to serious conditions. It is necessary to elucidate detailed clinical features of these AEs.

PATIENTS AND METHODS

Patients treated with anti-PD-1 monotherapy or in combination with anti-cytotoxic T cell lymphocyte-4 therapy at our hospital from January 2013 to December 2016 were identified. The patients' clinical characteristics and laboratory and radiologic findings were collected.

RESULTS

Adrenal insufficiency occurred in 3% of the patients. All patients were male. At the onset of symptoms, eosinophilia (>500/μl) was observed in four cases. Eosinophilia was observed more than a month before onset of symptoms in three cases. Other pituitary hormones remained relatively stable. Radiological evidence of pituitary inflammation was detected only in one case.

CONCLUSION

Most anti-PD1-related adrenal insufficiency cases involved an isolated ACTH deficiency. Eosinophilia may be an early indicator before the onset of symptoms.

Detection of EGFR mutations in NSCLC patients in clinical practice: Comparison between cobas and Scorpion ARMS method

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Background: Epidermal growth factor receptor (EGFR) mutation is the most important factor for determining the treatment strategy for non-small-cell lung cancers (NSCLCs). Currently, two methods (cobas and Scorpion ARMS) have been approved as companion diagnostics for using EGFR tyrosine kinase inhibitor (TKI). Although there are some differences in the spectrums and sensitivities for detecting EGFRmutations such as exon 19 deletions (ex19del), L858R and T790M mutations, the extent of the differences affecting clinical practice is unclear. Methods: All patients with NSCLC who underwent EGFR mutation tests and treated at our hospital from February 2014 to February 2016 were enrolled. To detect EGFR mutations, the Scorpion ARMS (S) method was used from 2014 to 2015 and thecobasEGFR Mutation Test (C) from 2015 to 2016. We retrospectively investigated the detection rate of each EGFRmutation type and compared the rates between the two methods. Results: A total of 1,287 patients were enrolled. To detect EGFR mutations, 627 patients were tested by the S method and 660 by the C method, respectively. Of 1287 patients, 910 patients underwent initial biopsy, whereas 121 patients underwent re-biopsy after EGFR-TKI failure. EGFRmutations were detected in 130 of 418 (31.1%) patients and 153 of 492 (31.1%) patients by the S and C methods, respectively in the initial biopsy (P = 0.982). However, the detection rate of ex19del was slightly lower in the S method (12.6%) than in the C method (16.3%) (P = 0.105). Conversely, the detection rate of L858R was lower in the C method (13.8%) than in the S method (16.7%), but the difference was not significant (P = 0.252). De novo T790M was detected in one (0.2%) patient by the S method and in none by the C method. In re-biopsy after EGFR-TKI failure, the detection rates of T790M were as follows: 19 of 55 patients (34.5%) by the S method and 20 of 66 (30.3%) by the C method (P = 0.619). Conclusions: The different spectrums and sensitivities of EGFR mutations between the S and C methods were observed; however, they did not significantly affect clinical practice.

Monitoring of peripheral lymphocyte and neutrophil counts to predict efficacy of nivolumab (nivo)

e20583

Background: Programmed death-1 (PD-1) antibody is a key drug for treating non-small cell lung cancer (NSCLC), but the response rate is about 20% in non-selected populations and efficacy is difficult to predict. We examined correlations between peripheral blood tests, including counts of lymphocytes (Lym), neutrophils (Neu), and C-reactive protein (CRP), and the efficacy of nivolumab (nivo) monotherapy. Methods: Eighty NSCLC patients treated with nivo (3mg/kg every 2 weeks) in our hospital between December 2015 and September 2016 were evaluated. Peripheral blood tests on day (d) 0 (the day before 1st nivo), d15 (the day of 2nd nivo), d29 (the day of 3rdnivo) were evaluated. Absolute counts and the change ratio (%) of Lym, Neu and CRP from baseline (d0) were calculated. Response to nivo was evaluated according to RECIST v1.1. Results: Response to nivo was partial response in 23 cases, stable disease in 13 and progressive disease (PD) in 44 patients (overall response rate, 28%; disease control rate, 45%). Absolute counts of Lym, Neu and CRP at baseline did not differ significantly between non-PD and PD (Lym, 1323/µl vs. 1376/µl; Neu, 4830/µl vs. 5189/µl; CRP, 3.48 mg/dl vs. 3.38 mg/dl). Neu was significantly increased from baseline to d15 and d29 in the PD population compared with the non-PD population (δNeu (d15): 25.2% vs. -6.3%, P= 0.008; δNeu (d29): 16.7% vs. -8.6%, P= 0.006). CRP was also significantly increased from baseline to d29 in the PD population compared with the non-PD population (δCRP: 60.1% vs. -21.2%, P= 0.010). In contrast, Lym was significantly increased from baseline to d29 in the non-PD population compared with the PD population (δLym: 9.6% vs. –6.7%, P= 0.010). Conclusions: Changes in peripheral blood test results after nivo differed between non-PD and PD populations. Monitoring of Neu and Lym and CRP may allow prediction of the efficacy of nivo.

Clinical and radiological features of advanced RET-rearranged lung cancer

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Background: RET fusion gene was found in 1–2% of non-small cell lung cancer (NSCLC). Most of the reports published so far investigated only surgical specimens, and details of advanced tumors were unknown. This study explored the clinical and radiological characteristics of RET-rearranged lung cancers in advanced stages. Methods: Among 1,074 advanced NSCLC patients who were treated at The Cancer Institute Hospital, Tokyo, from 2012 to 2016, 14 cases (14/1,074 = 1.3%) were treated as RET- rearranged lung cancer. The cases were identified by FISH and / or by RT-PCR (FISH 3, RT-PCR 2, FISH and RT-PCR 8, unknown 1). The fusion partner genes included KIF5B (n = 10), CCDC6 (n = 1). Three were unknown. The tumor size, location, and shape/margins of the primary tumor as well as lymphadenopathy and site of metastasis were recorded based on computed tomography (CT) images taken right before the initial chemotherapy. Results: The median age of the 14 patients was 64 years (range, 34–79), with 10 patients (71%) over 60 years old. Nine patients (64%) were women, whereas 10 patients (71%) were never smokers. Eight patients were classified as stage IV and 6 underwent recurrence after surgery. We successfully evaluated CT images at the initial chemotherapy of 12 patients. Of the 7 patients whose primary lesions were detectable, all were located peripherally and were of a solid tumor type without ground-glass, air bronchograms, or cavitation. The median size of the primary lesion was 3.0 cm (range, 1.2–6.8), and 3 lesions were less than 3.0 cm. Only 5 patients had lymphadenopathy (4 were of Stage IV, 1 was a recurrence), most of which were isolated with a median size of 1.5 cm (range, 1.2–3.5). The sites of distant metastases included 8 pleural disseminations, 5 lungs, 5 bones, 3 livers, 2 brains, and 0 adrenals. Conclusions: Advanced RET-rearranged lung cancer manifested as a relatively small and peripherally located solid primary lesion with isolated lymphadenopathy. Pleural dissemination was frequently observed, whereas brain metastasis was less frequent. These features differ from EGFR-mutated or ALK-fused lung cancers.

The efficacy and toxicity of osimertinib in T790M-positive NSCLC with acquired resistance to EGFR-TKI in clinical practice

e20575

Background: A Phase III study (AURA3) demonstrated that osimertinib prolonged PFS compared to platinum doublet in patients with T790M-positive non-small-cell lung cancer (NSCLC) exhibiting acquired resistance to epidermal growth factor receptor- tyrosine kinase inhibitor (EGFR-TKI). Although the patients in the study had good PS and only one prior EGFR-TKI treatment, most practical patients had multiple prior EGFR-TKI and poor PS. Moreover, several patients exhibited symptomatic central nervous system (CNS) metastasis in clinical practice. In this study, we evaluated the efficacy and toxicity of osimertinib in clinical practice. Methods: We retrospectively analyzed 30 patients who were treated with osimertinib at our hospital from April 11th 2016 to September 30th 2016. The efficacy and toxicity was compared between the patients with matched and unmatched AURA3 eligibility criteria. Efficacy was evaluated according to RECIST ver.1.1 and toxicity was evaluated using CTCAE ver.4.0. Results: A total of 9 out of 30 patients matched the AURA3 eligibility criteria (PS ≤ 1 and one prior EGFT-TKI) and 21 patients were unmatched (PS ≥ 2 or two or more EGFR-TKI or symptomatic CNS metastasis). The overall response rate(ORR) of osimertinib was 78% and 67% for the matched and unmatched patients, respectively. The disease control rate (DCR) was 100% and 90% for the matched and unmatched patients, respectively. In addition, the response rate of symptomatic CNS metastasis was 67%. Regarding toxicity, grade 3/4 toxicities were observed in 22% of the matched patients and 33% of the unmatched patients. In the matched patients, the most frequent AE was a rash (89%) and the frequent grade 3/4 toxicities were a rash (22%) and pneumonitis (11%). In unmatched patients, the most frequent AE was also a rash (57%), but the frequent grade 3/4 toxicities were pneumonitis (14%), rash (10%), and neutropenia (10%). Conclusions: Both the ORR and DCR in the unmatched patients were slightly lower than the matched patients; however, osimertinib was still found to be beneficial in clinical practice.

Preexistence of CT findings with usual interstitial pneumonia (UIP) pattern correlates to radiation pneumonitis (RP) in non-small cell lung cancer (NSCLC) patients receiving chemoradiotherapy (CRT)

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Background: RP is a major toxicity commonly observed in NSCLC patients who receive CRT; RP prediction is a critical issue. Although preexisting interstitial pneumonia (IP) is considered as one of the risk factors of RP, the correlation between interstitial lung shadows (ILSs) in the pretreatment CT scan and RP is not well examined. Methods: We reviewed patients with stage III NSCLC who received CRT at our hospital from January 2011 until December 2014. The pretreatment CT scans were retrospectively evaluated, and preexisting ILSs were classified according to the ATS/ERS/JRS/ALAT statement for idiopathic pulmonary fibrosis (IPF) as follows: UIP pattern, possible UIP pattern, and others (not UIP pattern). The incidence, severity, and features of RP were compared between ILS patterns. Results: In total, 105 patients with stage III NSCLC had received CRT. ILSs in pretreatment CT scans were identified in 16 (15.2%) of 105 patients. Of all the identified patterns, one (0.9%) was UIP pattern, six (5.7%) were possible UIP pattern, and nine (8.6%) were not UIP pattern. Grade 3 or higher RP was observed in 2 of 7 (28.6%) patients with UIP pattern or possible UIP pattern and 1 of 9 (11.1%) patients with not UIP pattern ( P = 0.55). RP that extended outside the irradiation field like an acute exacerbation of IP was observed in 4 of 7 (57.1%) patients with UIP pattern or possible UIP pattern and 1 of 9 (11.1%) patients with not UIP pattern ( P = 0.106). Conclusions: Preexistence of ILSs classified as UIP pattern or possible UIP pattern should be considered as a risk factor for severe or extensive RP after CRT.

The reasons why re-biopsies were not performed after failure with EGFR-TKI

e20540

Background: Repeat biopsy becomes important to determine subsequent treatment after failure of EGFR-TKI. However, some patients did not receive re-biopsy in real world. Here we retrospectively analyzed the reasons why the patients did not receive re-biopsy. Methods: We reviewed medical records of 235 patients treated with EGFR-TKI at our institution between January 2014 and September 2016 and analyzed the treatment, the progression site after failure of EGFR-TKI and the reasons why they did not receive re-biopsy. Results: 127 of 235 (54%) patients had tumor progression after treatment with EGFR-TKI and 93 (73.2%) of 127 patients received re-biopsy and 34 (26.8%) patients didn’t. The characteristics of 34 patients who did not received re-biopsy were; the median age, 67 years (29-83), male/ female: 12/22, PS0-1/2 ≥:27/7, stage IV/recurrence/other:20/10/4, smoking history never/ex/current: 15/17/2, histology : adeno/other 34/0, EGFR mutation type; 19del/L858R/Other = 13/15/6, prior EGFR-TKI; Gefitinib/Erlotinib/Afatinib/other: 22/9/2/1. The commonest reason why they did not receive re-biopsy was no target lesion to get biopsy (n = 13,38%). CT scans of these patients were retrospectively evaluated and it was confirmed that there were no lesions that could be accessed safely at that time. Central nervous system lesions, multiple small pulmonary lesions and bone metastasis were unaccessible lesions. Although 21 patients had accessible lesions including lung, superficial lymph nodes, pleural effusion, liver, they did not receive re-biopsy because of patient refusal (n = 9), worsening of general condition (n = 3), need for other therapy immediately (ex: chemotherapy, radiotherapy) (n = 3), old age (n = 2), existence of de novo T790M (n = 2), complications (n = 1) and physician’s choice (n = 1). Conclusions: Some patients who did not recieve re-biopsy had some target lesions and it could be increase the re-biopsy rate.