Clinical features of immature leukemias in children.

Early T-cell precursor acute lymphoblastic leukemia (ETP-ALL), mixed phenotypic acute leukemia (MPAL), and acute myeloid leukemia with minimal differentiation (AML-M0) all originate from immature hematopoietic progenitor cells and have a poor prognosis. We investigated the clinical characteristics of these immature leukemias in 17 children (ETP-ALL: 8, MPAL: 5, AML-M0: 4) at seven institutions. Clinical and laboratory findings were comparable across disease types. Eleven and six patients received ALL- and AML-oriented induction chemotherapy, with six and four achieving complete remission (CR), respectively. Five additional patients achieved CR after salvage with the other type of chemotherapy. Eight patients received hematopoietic cell transplantation (HCT) in first CR, and six survived without relapse. However, six of seven patients who did not receive HCT during first CR relapsed; all underwent HCT later, and only three survived. The 5-year event-free survival (EFS) and overall survival (OS) rate were 37% and 69%, respectively. Patients who achieved CR after induction chemotherapy and received HCT in first CR had favorable EFS and OS. Notably, all patients who received HCT in first CR survived 5 years after diagnosis. Appropriate induction chemotherapy and HCT in first CR could improve the outcome of immature leukemias.

CD30 expression in an emerging group of mesenchymal spindle cell neoplasms with ALK fusion detected by flow cytometry and immunohistochemistry.

An emerging group of spindle cell neoplasms harboring fusions involving NTRK or non-NTRK kinase genes often share characteristic S100 and/or CD34 expression; however, the diagnostic utility of immunohistochemical stains is not well established in this family owing to their lack of specificity. Recently, CD30 expression in spindle cell neoplasms with kinase gene fusions, such as NTRK, BRAF, RAF1, and RET, has been increasingly identified. We herein report a 10-year-old girl with high-grade spindle cell sarcoma of the neck. Prior to histopathological evaluation, flow cytometry (FCM) analysis and touch smear cytology of the tumor tissue revealed CD34+ and dimCD30+ spindle cell populations. Histopathologically, the case was characterized by monomorphic spindle-shaped cytomorphology with CD30, S100, and CD34 positivity and harbored close similarities with spindle cell neoplasms with NTRK or non-NTRK gene fusions. Subsequently, a comprehensive next-generation sequencing sarcoma panel identified a rare PLEKHH2::ALK fusion, and a diagnosis of ALK-rearranged spindle cell neoplasm was made. The patient showed significant tumor response to single-agent treatment with alectinib, an ALK-tyrosine kinase inhibitor. This case supports that CD30 is expressed in an ALK-rearranged mesenchymal neoplasm. The benefit of the early detection of CD30 expression by FCM for a prompt diagnosis and treatment is highlighted in the context of an aggressive clinical course. This case represents a learning experience regarding the need to the check the status of CD30 expression in these tumors and suggests the potential clinical benefits of CD30-targeted therapy.

Medical staff's sense of awareness of informed consent for adolescent cancer patients and the need for decision-making support practiced from the perspective of trauma-informed approach.

It has not been established how to assess children's and adolescents' decision-making capacity (DMC) and there has been little discussion on the way their decision-making (DM). The purpose of this study was to examine actual situation and factors related to difficulties in explaining their disease to adolescent cancer patients or obtaining informed consent (IC). The cross-sectional questionnaire survey was conducted. Physicians who have been treating adolescent cancer patients for at least five years answered a self-administered questionnaire uniquely developed about clinical difficulties in explaining, IC and factors related patient's refusal of medical treatment (RMT). Descriptive statistics for each item and a polychoric correlation analysis of the problems and factors related to the explanation were conducted. As a result, fifty-six physicians were participated (rate of return: 39%). Explaining the disease and treatment to patients (83.9%), IC to patients (80.4%), and explaining the disease and treatment to parents (78.6%) was particularly problematic. Difficulties to provide support related with patient's refusal of medical treatment and to explain disease and treatment for patient and parents were related to difficulties obtaining IC for the patient. Conclusion: There are clinically difficult to explain for the patient or parents and to obtain IC for the patient. It is necessary to establish a disease acceptance assessment tool for the adolescence generation so that it can be applied in the field.

Feasibility and preliminary effectiveness of a psychosocial support program for adolescent and young adult cancer patients in clinical practice: a retrospective observational study.

PURPOSE: Adolescent and young adult cancer patients (AYAs) often experience profound psychological distress, with various unmet supportive care needs that can be alleviated with appropriate screening and attention by healthcare workers. The Distress Thermometer and Problem List-Japanese version (DTPL-J) is our previously developed screening tool to facilitate individual support of AYAs. This study evaluated the feasibility and preliminary effectiveness of a psychosocial support program based on the DTPL-J for AYAs in clinical practice. METHODS: This multicenter, retrospective, observational study included 19 of 126 wards and 9 of 75 outpatient clinics at 8 institutions in Japan. Over 200 patients were expected to participate during the eligibility period. Patients participated in a support program at least once, and approximately once a month based on the DTPL-J results. The program was evaluated using the RE-AIM (Reach, Effectiveness, Adoption, Implementation, and Maintenance) implementation framework. RESULTS: The screening rate of the 361 participants was 90.3%, suggesting high feasibility. Distress Thermometer scores, the number of supportive care needs, and the rates of AYAs with high distress were significantly reduced 1 month after screening (p < 0.05), suggesting the preliminary effectiveness of the program. The program was continued at the 8 institutions as part of routine care after the study. CONCLUSION: Analysis using the RE-AIM suggested the sufficient feasibility and preliminary effectiveness of a psychosocial support program based on the DTPL-J for AYAs. TRIAL REGISTRATION: University Hospital Medical Information Network (UMIN CTR) UMIN000042857. Registered 25 December 2020-Retrospectively registered.

Current Status and Issues of the Japan Oncofertility Registry.

Purpose: Fertility preservation (FP) is becoming increasingly common among child, adolescent, and young-adult (CAYA) patients with cancer. However, Japan has long lacked definite estimates of utilization rates for FP services among CAYA patients with cancer, and little is known about disease/FP outcomes among users. Therefore, the Japan Society for Fertility Preservation (JSFP) launched the Japan Oncofertility Registry (JOFR) in 2018 and started the online registration of information regarding primary disease, FP, and data on prognosis and pregnancy outcomes. This study reports the analytical results of FP data registered in the JOFR as of 2021. Methods: Data about patients' primary disease(s), treatment courses, cancer and pregnancy outcomes, and specific procedures were extracted from the JOFR and analyzed. Results: In 2021, 1244 patients received counseling or treatment related to FP (540 males, 704 females). While the numbers of males in each age group were approximately equal, most females were aged between 31 and 40 years. In total, 490 male and 540 female patients underwent FP procedures. Leukemia, testicular cancer, and malignant lymphoma accounted for the majority of male cases seeking treatment, whereas breast cancer was the primary disease in two-thirds of the females. Since 1999, 395 patients have accumulatively experienced subsequent pregnancy. Conclusions: As of January 2022, >7000 cases from >100 fertility facilities have been registered in the JOFR. In the future, maintaining JOFR to disseminate information on cancer prognoses, pregnancy rates, and other oncofertility outcomes is expected to drive further expansion of oncofertility services in Japan.

BCL6 inhibition ameliorates resistance to ruxolitinib in CRLF2-rearranged acute lymphoblastic leukemia.

Philadelphia chromosome-like acute lymphoblastic leukemia (Ph-like ALL) is an intractable disease and most cases harbor genetic alterations that activate JAK or ABL signaling. The commonest subtype of Ph-like ALL exhibits a CRLF2 gene rearrangement that brings about JAK1/2-STAT5 pathway activation. However, JAK1/2 inhibition alone is insufficient as a treatment, so combinatorial therapies targeting multiple signals are needed. To better understand the mechanisms underlying the insufficient efficacy of JAK inhibition, we explored gene expression changes upon treatment with a JAK1/2 inhibitor (ruxolitinib) and found that elevated BCL6 expression was one such mechanism. Upregulated BCL6 suppressed the expression of TP53 along with its downstream cell cycle inhibitor p21 (CDKN2A) and pro-apoptotic molecules, such as FAS, TNFRSF10B, BID, BAX, BAK, PUMA, and NOXA, conferring cells some degree of resistance to therapy. BCL6 inhibition (with FX1) alone was able to upregulate TP53 and restore the TP53 expression that ruxolitinib had diminished. In addition, ruxolitinib and FX1 concertedly downregulated MYC. As a result, FX1 treatment alone had growth-inhibitory and apoptosis- sensitizing effects, but the combination of ruxolitinib and FX1 more potently inhibited leukemia cell growth, enhanced apoptosis sensitivity, and prolonged the survival of xenografted mice. These findings provide one mechanism for the insufficiency of JAK inhibition for the treatment of CRLF2-rearranged ALL and indicate BCL6 inhibition as a potentially helpful adjunctive therapy combined with JAK inhibition.

High-dose thiotepa, in conjunction with melphalan, followed by autologous hematopoietic stem cell transplantation in patients with pediatric solid tumors, including brain tumors.

Among pediatric malignancies, solid tumors, particularly within the central nervous system (CNS), are common. Thiotepa, a myeloablative, high-dose chemotherapeutic (HDT) treatment administered prior to autologous hematopoietic stem cell transplantation (HSCT), can cross the blood-brain barrier and rapidly penetrate the CNS. We evaluated thiotepa HDT in conjunction with melphalan in Japanese patients with pediatric CNS/non-CNS solid tumors in a multicenter, open-label, non-comparative study. Thiotepa (200 mg/m2/day) was administered intravenously (IV) over 24 h on days -12, -11, -5, and -4 before scheduled HSCT. Melphalan (70 mg/m2/day) was administered IV over 1 h on days -11, -5, and -4. The safety analysis population comprised 41 patients, of whom 16 (39.0%) had solid tumors and 25 (61.0%) had brain tumors. The most frequently reported adverse events were diarrhea (40/41 [97.6%] patients) and febrile neutropenia (34/41 [82.9%]). No unexpected safety events were observed, and no events resulted in death or treatment discontinuation. All patients experienced bone marrow suppression and 39/41 (95.1%) achieved engraftment (neutrophil count ≥500/mm3 for 3 consecutive days after HSCT). The survival rate at day 100 post-autologous HSCT was 100%. These data confirm the safety of IV thiotepa plus melphalan HDT prior to autologous HSCT for patients with pediatric CNS/non-CNS solid tumors. Trial registration: JapicCTI-173654.

[Current Status and Challenges in Oncofertility for Pediatric Cancer Patients].

Infertility is a frequent late effect of cancer treatment that significantly affects cancer survivors' quality of life. In recent years, with advances in oncofertility, the number of children with cancer receiving fertility preservation therapy has increased. However, specific challenges exist in pediatric cancer patients. First, fertility preservation therapy for children with cancer relies significantly on their age and sex. Ovarian tissue cryopreservation is possible until puberty in females, and after menarche, the ovarian tissues and oocytes can be preserved. Sperm cryopreservation is a well-established technique for male adolescents. However, prepubertal boys are deprived of such methods. Second, ethical considerations are important when providing information about treatment-related infertility risk and fertility preservation to children. Third, because most childhood cancer survivors cannot remember their cancer treatment, information should be provided repeatedly, according to the patient's growth and level of understanding. Currently, the provision of information to patients with childhood cancer is insufficient. Therefore, the PanCareLIFE Consortium and the International Late Effects of Childhood Cancer Guideline Harmonization Group have developed clinical practice guidelines for ongoing communication regarding treatment-related infertility risk and fertility preservation in patients with a history of childhood, adolescence, or young adult cancer. In April 2021, Japan implemented a public subsidy system to partially fund the expenses related to oncofertility. In the future, multidisciplinary healthcare providers should collaborate to provide appropriate information and support to the patients and their families.

Analysis of Ser/Thr Kinase HASPIN-Interacting Proteins in the Spermatids.

HASPIN is predominantly expressed in spermatids, and plays an important role in cell division in somatic and meiotic cells through histone H3 phosphorylation. The literature published to date has suggested that HASPIN may play multiple roles in cells. Here, 10 gene products from the mouse testis cDNA library that interact with HASPIN were isolated using the two-hybrid system. Among them, CENPJ/CPAP, KPNA6/importin alpha 6, and C1QBP/HABP1 were analyzed in detail for their interactions with HASPIN, with HASPIN phosphorylated C1QBP as the substrate. The results indicated that HASPIN is involved in spermatogenesis through the phosphorylation of C1QBP in spermatids, and also may be involved in the formation of centrosomes.

Favorable prognosis of vaccine-associated immune thrombocytopenia in children is correlated with young age at vaccination: Retrospective survey of a nationwide disease registry.

Childhood vaccine-associated immune thrombocytopenia (ITP) has a mostly favorable prognosis. To identify factors associated with prognosis, a retrospective survey was conducted with children with ITP who were registered in the Japanese Society of Pediatric Hematology/Oncology registry from 2008 to 2011. A total of 477 patients were categorized into four groups by event preceding ITP onset: vaccine-precedence (VP; n = 43), vaccine/infection-precedence (VIP; n = 34), infection-precedence (IP; n = 162), and no vaccine/infection-precedence (NVI; n = 238). Compared to IP and NVI, VP and VIP were significantly younger at diagnosis, with the age distribution peaking at infancy, and more frequently had favorable prognosis. Time to platelet recovery to 100 × 103/µL was significantly faster for VP and VIP than NVI. Multivariate Cox regression analysis with sex, age at diagnosis, infection-precedence, and vaccine-precedence as variables revealed age < 36 months (HR 0.992, 95% CI 0.989-0.995; p < 0.001) and male sex (HR 0.770, 95% CI 0.623-0.952; p = 0.015) as associated factors, but not infection-precedence (p = 0.149) or vaccine-precedence (p = 0.650). In subgroup analysis in patients < 36 months, age at diagnosis (p < 0.001) was the only associated factor. Favorable prognosis of childhood vaccine-associated ITP is correlated with young age at vaccination, but not with vaccination itself.

Clinical outcome of patients with recurrent or refractory localized Ewing's sarcoma family of tumors: A retrospective report from the Japan Ewing Sarcoma Study Group.

BACKGROUND: Patients with Ewing's sarcoma family of tumors (ESFT) who experience relapse or progression have a poor prognosis. AIM: This study aimed to identify the prognostic and therapeutic factors affecting overall survival (OS) of patients with recurrent or refractory localized ESFT. METHODS AND RESULTS: Thirty-eight patients with localized ESFT who experienced first relapse or progression between 2000 and 2018 were retrospectively reviewed. The 5-year OS rate of the entire cohort was 48.3% (95% confidence interval, 29.9%-64.5%). Multivariate analysis of OS identified time to relapse or progression, but not stem cell transplantation (SCT), as the sole independent risk factor (hazard ratio, 35.8; P = .002). Among 31 patients who received salvage chemotherapy before local treatment, 21 received chemotherapy regimens that are not conventionally used for newly diagnosed ESFT. The objective response rate to first-line salvage chemotherapy was 55.2% in the 29 evaluable patients. Time to relapse or progression was significantly associated with response to first-line salvage chemotherapy (P = .006). CONCLUSIONS: The present study fails to demonstrate significant clinical benefit of SCT for recurrent or refractory localized ESFT. Recently established chemotherapy regimens may increase the survival rate of patients with recurrent or refractory localized ESFT while attenuating the beneficial effect of SCT.

Prognostic and therapeutic factors influencing the clinical outcome of metastatic Ewing sarcoma family of tumors: A retrospective report from the Japan Ewing Sarcoma Study Group.

BACKGROUND: The prognosis of patients with metastatic Ewing sarcoma family of tumors (ESFT) remains poor. PROCEDURE: We retrospectively analyzed 57 patients diagnosed with metastatic ESFT between 2000 and 2018 to identify prognostic and therapeutic factors affecting the clinical outcome. RESULTS: The 3-year overall survival (OS) rate of the entire cohort was 46.8% (95% confidence interval [CI], 33.0-59.4%). Treatment-related death was not observed. Multivariate analysis identified stem cell transplantation (SCT), response to first-line chemotherapy, and bone metastasis as independent risk factors for OS. Objective response rate to first-line chemotherapy was 65.1% in the 43 evaluable patients. There was no significant difference in the response to different types of first-line chemotherapy. Among patients with lung metastasis alone, the 3-year OS rate was higher in 13 patients who received local treatment than in four who did not, although the difference was not significant. CONCLUSIONS: One possible reason for the high OS rates was the absence of treatment-related mortality even in patients receiving SCT, which could be attributed to advances in the management of post-SCT complications. Novel first-line chemotherapy strategies need to be established to improve the disease status prior to SCT in a higher proportion of patients.

Association between sites and severity of eczema and the onset of cow's milk and egg allergy in children.

BACKGROUND: Cow's milk allergy (CMA) and egg allergy (EA) are common and can reduce quality of life in children. Infantile eczema is a well-established risk factor for the onset of food allergy via transdermal sensitization; however, various types of infantile eczema have not yet been evaluated. Therefore, we assessed the association between CMA and EA and the sites and the severity of infantile eczema. METHODS: This retrospective study was based on data from patients aged 2-19 years with atopic disease who were treated between July 2015 and March 2019 in a pediatric allergy clinic in Japan. Data regarding the history of IgE-mediated symptoms, eczema in the first year of life, parental history of atopic diseases, and infantile nutrition were collected. RESULTS: A total of 289 patients were included in the study, of which 81 and 111 children had IgE-mediated CMA and EA, respectively. The rates of CMA and EA were higher in the children with infantile eczema than in those without (30% vs. 9% and 42% vs. 21%). The rate of CMA was also higher in children with eczema on the face. Significant differences were noted in the rate of CMA among children with facial eczema of exudation (adjusted odds ratio 2.398; P = 0.017) and papules (adjusted odds ratio 2.787; P = 0.008), using multivariate analysis. CONCLUSION: The rate of IgE-mediated CMA was high among children with atopic disease having severe facial eczema during infancy.

Impact on dose distribution and volume changes of a bioabsorbable polyglycolic acid spacer during chemo-proton therapy for a pediatric Ewing sarcoma.

The clinical utility of a recently developed bioabsorbable polyglycolic acid (PGA) spacer has not yet been established in pediatric patients; therefore, we aimed to investigate its utility during chemo-proton therapy for pediatric cancer. Proton depth-dose curves were obtained in a water phantom with or without the spacer. Computed tomography (CT) scans were performed for the PGA spacer immersed in saline for 2 weeks to measure CT numbers and estimate the relative stopping power (RSP) for the proton beams. The spacer was placed in a patient with sacral Ewing sarcoma receiving 55.8 Gy [relative biological effectiveness (RBE)] in 31 fractions and was evaluated using CT scans performed every other week. In addition, the images were used to quantitatively evaluate changes in volume and RSP of the spacer and dose distributions in normal tissues. The spacer immersed in saline had a CT number of 91 ± 7 (mean ± standard deviation) Hounsfield units, and the corresponding RSP was predicted to be 1.07 ± 0.01. The measured RSP agreed with the predicted one. The volumes of the large bowel and rectum receiving ≥45 Gy(RBE) (V45Gy) were significantly reduced by placing the spacer; V45Gy without and with the spacer were 48.5 and 0.01%, respectively, for the rectum and 7.2 and 0%, respectively, for the large bowel. The volume of the spacer and RSP decreased at rates of 4.6 and 0.44% per week, respectively, whereas the target dose coverage was maintained until the end of treatment. The PGA spacer was considered effective for pediatric cancer patients undergoing chemo-proton therapy.

A female patient with retinoblastoma and severe intellectual disability carrying an X;13 balanced translocation without rearrangement in the RB1 gene: a case report.

BACKGROUND: Female carriers of a balanced X; autosome translocation generally undergo selective inactivation of the normal X chromosome. This is because inactivation of critical genes within the autosomal region of the derivative translocation chromosome would compromise cellular function. We here report a female patient with bilateral retinoblastoma and a severe intellectual disability who carries a reciprocal X-autosomal translocation. CASE PRESENTATION: Cytogenetic and molecular analyses, a HUMARA (Human androgen receptor) assay, and methylation specific PCR (MSP) and bisulfite sequencing were performed using peripheral blood samples from the patient. The patient's karyotype was 46,X,t(X;13)(q28;q14.1) by G-banding analysis. Further cytogenetic analysis located the entire RB1 gene and its regulatory region on der(X) with no translocation disruption. The X-inactivation pattern in the peripheral blood was highly skewed but not completely selected. MSP and deep sequencing of bisulfite-treated DNA revealed that an extensive 13q region, including the RB1 promoter, was unusually methylated in a subset of cells. CONCLUSIONS: The der(X) region harboring the RB1 gene was inactivated in a subset of somatic cells, including the retinal cells, in the patient subject which acted as the first hit in the development of her retinoblastoma. In addition, the patient's intellectual disability may be attributable to the inactivation of the der(X), leading to a 13q deletion syndrome-like phenotype, or to an active X-linked gene on der (13) leading to Xq28 functional disomy.

Bortezomib-containing therapy in Japanese children with relapsed acute lymphoblastic leukemia.

Outcomes of children treated for relapsed acute lymphoblastic leukemia (ALL) remain poor. Bortezomib (BZM), a proteasome inhibitor, has shown promising activity against lymphoid malignancies. We conducted a phase I study to evaluate the safety and tolerability of multidrug chemotherapy including BZM in Japanese children with relapsed ALL. Three of five children with relapsed ALL enrolled in the study between November 2014 and April 2016 were evaluated. BZM (1.3 mg/m2) was administered on days 8, 11, 15, and 18 of multidrug induction chemotherapy. Pharmacokinetic studies were performed. Age at study entry was 5, 7, and 7 years old, respectively. Two patients had hyperdiploid B-precursor ALL, and one had T cell ALL. Although all patients experienced grade 3-4 hematologic toxicity and grade 3 elevation of aminotransferases, no dose-limiting toxicities were observed. The maximum tolerated dose was defined as 1.3 mg/m2. Peripheral neuropathy and respiratory complications were not observed. Complete remission was achieved in all three patients. The mean maximum plasma concentration and area under the concentration-time curve was 74.0 ng/mL and 73.9 ng h/mL, respectively. Thus, adding BZM to 5-drug induction chemotherapy appears safe and well-tolerated in Japanese children with relapsed ALL.

Pharmacokinetics of thiotepa in high-dose regimens for autologous hematopoietic stem cell transplant in Japanese patients with pediatric tumors or adult lymphoma.

PURPOSE: Thiotepa is used in high-dose chemotherapy (HDT) before autologous hematopoietic stem cell transplantation (HSCT) to treat solid tumors and hematological malignancies. This Phase 1 study was conducted to establish the pharmacokinetics (PK) of thiotepa in a Japanese population. METHODS: HDT/HSCT was performed in pediatric patients (≥ 2 years) with solid tumors or brain tumors (thiotepa 200 mg/m2/day IV-infused over 24 h on HSCT Days - 12, - 11, - 5, and - 4 and melphalan 70 mg/m2/day IV-infused over 1 h on Days - 11, - 5, and - 4) and adult patients (≥ 16 years) with malignant lymphoma (thiotepa 200 mg/m2/day 2-h IV-infusion on HSCT Days - 4 and - 3 plus busulfan 0.8 mg/kg 2-h IV-infusion every 6 h from HSCT Days - 8 to - 5). Pharmacokinetics of thiotepa were assessed following initial dose. Safety and efficacy were also evaluated. RESULTS: Nine pediatric and 10 adult patients were enrolled. Mean volume of distribution (Vz) of thiotepa normalized with body surface area (BSA) was lower for pediatric patients (16.4 L/m2) compared with adult patients (26.4 L/m2) as expected due to the higher specific surface area of children. Clearance and biological half-life were similar between pediatric and adult patients. Two serious adverse events (cardiac arrest and pulmonary edema) were observed. Survival rate (Day 100 post-HSCT) was 77.8% (95% CI 36.5-93.9%) for pediatric patients and 100% for adult patients. CONCLUSION: Thiotepa elimination was comparable in pediatric and adult patients with cancer. Lower Vz in pediatric compared with adult patients was expected. HDT with thiotepa prior to autologous HSCT was well tolerated. STUDY REGISTRATION: Japic CTI-163433.

Wide-field Single-photon Optical Recording in Brain Slices Using Voltage-sensitive Dye.

Wide-field single photon voltage-sensitive dye (VSD) imaging of brain slice preparations is a useful tool to assess the functional connectivity in neural circuits. Due to the fractional change in the light signal, it has been difficult to use this method as a quantitative assay. This article describes special optics and slice handling systems, which render this technique stable and reliable. The present article demonstrates the slice handling, staining, and recording of the VSD-stained hippocampal slices in detail. The system maintains physiological conditions for a long time, with good staining, and prevents mechanical movements of the slice during the recordings. Moreover, it enables staining of slices with a small amount of the dye. The optics achieve high numerical aperture at low magnification, which allows recording of the VSD signal at the maximum frame rate of 10 kHz, with 100 pixel x 100-pixel spatial resolution. Due to the high frame rate and spatial resolution, this technique allows application of the post-recording filters that provide sufficient signal-to-noise ratio to assess the changes in neural circuits.