Novel Insights Into the International Association for the Study of Lung Cancer Grading System for Lung Adenocarcinoma.

The new grading system for lung adenocarcinoma proposed by the International Association for the Study of Lung Cancer (IASLC) defines prognostic subgroups on the basis of histologic patterns observed on surgical specimens. This study sought to provide novel insights into the IASLC grading system, with particular focus on recurrence-specific survival (RSS) and lung cancer-specific survival among patients with stage I adenocarcinoma. Under the IASLC grading system, tumors were classified as grade 1 (lepidic predominant with <20% high-grade patterns [micropapillary, solid, and complex glandular]), grade 2 (acinar or papillary predominant with <20% high-grade patterns), or grade 3 (≥20% high-grade patterns). Kaplan-Meier survival estimates, pathologic features, and genomic profiles were investigated for patients whose disease was reclassified into a higher grade under the IASLC grading system on the basis of the hypothesis that they would strongly resemble patients with predominant high-grade tumors. Overall, 423 (29%) of 1443 patients with grade 1 or 2 tumors classified based on the predominant pattern-based grading system had their tumors upgraded to grade 3 based on the IASLC grading system. The RSS curves for patients with upgraded tumors were significantly different from those for patients with grade 1 or 2 tumors (log-rank P < .001) but not from those for patients with predominant high-grade patterns (P = .3). Patients with upgraded tumors had a similar incidence of visceral pleural invasion and spread of tumor through air spaces as patients with predominant high-grade patterns. In multivariable models, the IASLC grading system remained significantly associated with RSS and lung cancer-specific survival after adjustment for aggressive pathologic features such as visceral pleural invasion and spread of tumor through air spaces. The IASLC grading system outperforms the predominant pattern-based grading system and appropriately reclassifies tumors into higher grades with worse prognosis, even after other pathologic features of aggressiveness are considered.

Establishment of artificial intelligence model for precise histological subtyping of lung adenocarcinoma and its application to quantitative and spatial analysis.

BACKGROUND: The histological subtype of lung adenocarcinoma is a major prognostic factor. We developed a new artificial intelligence model to classify lung adenocarcinoma images into seven histological subtypes and adopted the model for whole-slide images to investigate the relationship between the distribution of histological subtypes and clinicopathological factors. METHODS: Using histological subtype images, which are typical for pathologists, we trained and validated an artificial intelligence model. Then, the model was applied to whole-slide images of resected lung adenocarcinoma specimens from 147 cases. RESULT: The model achieved an accuracy of 99.7% in training sets and 90.4% in validation sets consisting of typical tiles of histological subtyping for pathologists. When the model was applied to whole-slide images, the predominant subtype according to the artificial intelligence model classification matched that determined by pathologists in 75.5% of cases. The predominant subtype and tumor grade (using the WHO fourth and fifth classifications) determined by the artificial intelligence model resulted in similar recurrence-free survival curves to those determined by pathologists. Furthermore, we stratified the recurrence-free survival curves for patients with different proportions of high-grade components (solid, micropapillary and cribriform) according to the physical distribution of the high-grade component. The results suggested that tumors with centrally located high-grade components had a higher malignant potential (P < 0.001 for 5-20% high-grade component). CONCLUSION: The new artificial intelligence model for histological subtyping of lung adenocarcinoma achieved high accuracy, and subtype quantification and subtype distribution analyses could be achieved. Artificial intelligence model therefore has potential for clinical application for both quantification and spatial analysis.

Clinical utility of the Oncomine Dx Target Test multi-CDx system and the possibility of utilizing those original sequence data.

BACKGROUND: Companion diagnostic tests play a crucial role in guiding treatment decisions for patients with non-small cell lung cancer (NSCLC). The Oncomine Dx Target Test (ODxTT) Multi-CDx System has emerged as a prominent companion diagnostic method. However, its efficacy in detecting driver gene mutations, particularly rare mutations, warrants investigation. AIMS: This study aimed to assess the performance of the ODxTT in detecting driver gene mutations in NSCLC patients. Specifically, we aimed to evaluate its sensitivity in detecting epidermal growth factor receptor (EGFR) mutations, a key determinant of treatment selection in NSCLC. MATERIALS AND METHODS: We conducted a retrospective analysis of NSCLC patients who underwent testing with the ODxTT at Keio University Hospital between May 2020 and March 2022. Patient samples were subjected to both DNA and RNA tests. Driver gene mutation status was assessed, and instances of missed mutations were meticulously examined. RESULTS: Of the 90 patients, five had nucleic acid quality problems, while 85 underwent both DNA and RNA tests. Driver gene mutations were detected in 56/90 (62.2%) patients. Of the 34 patient specimens, driver mutations were not detected using the ODxTT; however, epidermal growth factor receptor (EGFR) mutations were detected using polymerase chain reaction-based testing in two patients, and a KRAS mutation was detected by careful examination of the sequence data obtained using the ODxTT in one patient. For the above three cases, carefully examining the gene sequence information obtained using the ODxTT could identify driver mutations that were not mentioned in the returned test results. Additionally, we confirmed comparable instances of overlook results for EGFR mutations in the dataset from South Korea, implying that this type of oversight could occur in other countries using the ODxTT. EGFR mutation was missed in ODxTT in Japan (6.3%, 2/32), South Korea (2.0%, 1/49), and overall (3.7%, 3/81). CONCLUSION: Even if sufficient tumor samples are obtained, rare EGFR mutations (which are excluded from the ODxTT's genetic mutation list) might not be detected using the current ODxTT system due to the program used for sequence analysis. However, such rare EGFR mutations can still be accurately detected on ODxTT's sequence data using next-generation sequencing.

Clinicopathological predictors of postoperative long-term myasthenic status in resected thymoma with myasthenia gravis.

PURPOSE: Surgical patients with thymoma and myasthenia gravis (MG) must have their MG status and oncological outcomes critically monitored. We aimed to identify clinicopathological predictors of the postoperative MG status. METHODS: We conducted a retrospective review of 40 consecutive surgical patients with MG-related thymomas between 2002 and 2020. The quantitative myasthenia gravis score (QMGS) and Myasthenia Gravis Foundation of America post-intervention status (MGFA-PIS) were used to evaluate postoperative MG status. RESULTS: All patients underwent extended total thymectomy. The most common WHO type was type B2 (32%), while 65% of patients had type B1-B3 and 35% had type A-AB thymomas. Eleven patients (28%) achieved controlled MG status in MGFA-PIS 6 months after surgery. This controlled status was observed more frequently in type A-AB than in B1-B3 (57% vs. 12%, p = 0.007). In a multivariate analysis, WHO type (A-AB or B1-B3) was an independent predictor of worsening episodes of MG based on the QMGS (Type B1-B3, hazard ratio: 3.23, 95% confidence interval: 1.12-9.25). At the last follow-up, 23 patients (58%) achieved controlled MG status. The 5-year overall survival rate of all patients was 93.7%. CONCLUSION: The WHO type of thymoma is an informative predictor of postoperative MG status in patients with MG-related thymoma.

[Clinicopathological Features and Imaging Characteristics of Pulmonary Mucosa-associated Lymphoid Tissue Lymphoma].

BACKGROUND: Pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma is a rare disease. We report seven cases of pulmonary MALT lymphoma. CASES: Chest computed tomography (CT) revealed various morphological features, including a solitary mass, a solid nodule, and ground-glass opacity. Multiple nodules were observed in one patient. However, the tumor margins were ill-defined in all seven cases, and air bronchograms were identified in five cases. The solitary mass was found to extend along the pulmonary lymphatic vessels. Six patients underwent R0 resection, while one underwent an open lung biopsy. Histopathological findings in all seven cases showed lymphoepithelial lesions. Regarding their immunohistological findings, all patients were diagnosed with pulmonary MALT lymphoma. Two patients received postoperative chemotherapy with rituximab. The progression-free survival time was 52 (range, 22-122) months. Postoperative course was uneventful in all patients. CONCLUSION: MALT lymphoma is characterized by an ill-defined margin, air bronchogram, and tumor extension along the pulmonary lymphatic vessels, all of which aid in diagnosis. MALT lymphoma is a low-grade lymphoma, and the prognosis is favorable. Therefore, follow-up examination without treatment can be one of the therapeutic options if patients are diagnosed with pulmonary MALT lymphoma.

Genotype-phenotype mapping of a patient-derived lung cancer organoid biobank identifies NKX2-1-defined Wnt dependency in lung adenocarcinoma.

Human lung cancer is a constellation of tumors with various histological and molecular properties. To build a preclinical platform that covers this broad disease spectrum, we obtained lung cancer specimens from multiple sources, including sputum and circulating tumor cells, and generated a living biobank consisting of 43 lines of patient-derived lung cancer organoids. The organoids recapitulated the histological and molecular hallmarks of the original tumors. Phenotypic screening of niche factor dependency revealed that EGFR mutations in lung adenocarcinoma are associated with the independence from Wnt ligands. Gene engineering of alveolar organoids reveals that constitutive activation of EGFR-RAS signaling provides Wnt independence. Loss of the alveolar identity gene NKX2-1 confers Wnt dependency, regardless of EGFR signal mutation. Sensitivity to Wnt-targeting therapy can be stratified by the expression status of NKX2-1. Our results highlight the potential of phenotype-driven organoid screening and engineering for the fabrication of therapeutic strategies to combat cancer.

Concurrent de novo Thymoma-associated Paraneoplastic Type 1 Autoimmune Hepatitis and Pure Red Cell Aplasia after Thymectomy: A Case Report and Literature Review.

The precise manipulation of immune tolerance is the holy grail of immunotherapies for both autoimmunity and cancer immunity. Thymomas are well known to be associated with autoimmune diseases. The exact mechanism by which autoreactivity is induced after thymectomy remains to be elucidated. We herein present the case of a 50-year-old lady with concurrent de novo type 1 autoimmune hepatitis (AIH) and pure red cell aplasia (PRCA), 1 month after undergoing a successful total thymectomy for combined squamous cell carcinoma and thymoma (Masaoka stage II). Corticosteroids yielded short-term effects for both AIH and PRCA. Literature on thymoma-associated AIH, an extremely rare immune-related comorbidity, was also reviewed.

Successful Steroid Treatment of Pembrolizumab-induced Agranulocytosis That Developed after Splenectomy in a Patient with Non-small-cell Lung Cancer.

Neutropenia, a rare immune-related adverse event, affects patients receiving treatment with immune checkpoint inhibitors (ICIs). We herein report a case of pembrolizumab-induced agranulocytosis. An 83-year-old man was diagnosed with advanced-stage lung carcinoma concomitant with splenomegaly complicated by hypersplenism, causing pancytopenia. To avoid the risk of bone marrow suppression due to cytotoxic chemotherapy, pembrolizumab monotherapy was chosen. However, the patient developed agranulocytosis despite the resolution of pancytopenia through splenectomy performed after the fourth pembrolizumab cycle. Neutrophil counts improved after steroid treatment but not after granulocyte colony-stimulating factor treatment. This case demonstrated that neutropenia can sometimes develop abruptly after several ICI therapy cycles.

Long-Term Treatment-Free Survival After Multimodal Therapy in a Patient with Stage IV Lung Adenocarcinoma.

We report the first case of a patient with non-small cell lung cancer (NSCLC) with malignant pleural effusion (MPE) who achieved disease- and treatment-free survival for nearly 10 years. A 50-year-old man was diagnosed with NSCLC with MPE and underwent chemotherapy and salvage thoracic surgery. The patient received chemotherapy with cisplatin, pemetrexed, and bevacizumab, and a partial response was achieved. After informed consent was obtained from the patient, right middle lobectomy was performed to achieve local tumor control. Postoperative adjuvant chemotherapy with pemetrexed and bevacizumab was discontinued after almost 1 year of chemotherapy due to side effects such as diarrhea and muscle weakness. The patient has survived without recurrence of lung cancer for more than 11 years after being diagnosed and nearly 10 years after discontinuing chemotherapy.

Hemoptysis after coil embolization for pulmonary arteriovenous malformation: Histopathological confirmation of bronchial epithelium extension.

Coil embolization is widely performed for pulmonary arteriovenous malformations (PAVMs). We describe herein 2 cases of hemoptysis during long-term follow-up after coil embolization for PAVMs. For both cases, lobectomy was performed and histopathological examinations revealed chronic inflammation and bronchial epithelium extension into the sac of the PAVM. In addition, we performed a systematic review of previous reports of hemoptysis after embolization for PAVMs.

A 70-Year-Old Woman With Long-Term Nonresolving Pneumonia.

CASE PRESENTATION: A 70-year-old woman who had received a diagnosis of pneumonia in the right lower lobe was treated with antibiotics at a general practitioner's clinic 9 months earlier. Her pneumonia had improved, but the cough and lung infiltrates persisted for > 6 months, so the patient was referred to our hospital. She had undergone surgery for breast cancer 30 years earlier but had no other medical history. She was not taking any medications and had no history of smoking, including passive smoking.

MUC6 expression is a preferable prognostic marker for invasive mucinous adenocarcinoma of the lung.

Gastric gland mucin consists of core protein MUC6 with residues heavily glycosylated by unique O-glycans carrying α1,4-linked N-acetylglucosamine (αGlcNAc). αGlcNAc-glycosylated MUC6 protein is seen in normal gastric and duodenal glands. Decreased αGlcNAc glycosylation on MUC6-positive tumor cells is often observed in premalignant lesions of the stomach, pancreas, and bile duct, and decreased MUC6 expression is seen in invasive cancer of these organs. Lung cancer (LC) is the most common cause of cancer death worldwide. Recently, the adenocarcinoma subtype has become the most common histological subtype of LC, and one of its invasive forms is invasive mucinous adenocarcinoma (IMA). Currently, prognostic markers of LC IMA are unknown. Here, we analyzed MUC5AC, MUC6, and αGlcNAc expression in 54 IMA LC cases. MUC5AC was positively expressed in 50 (93%), MUC6 in 38 (70%), and αGlcNAc in 19 (35%). Each expression level was scored from 0 to 3. The αGlcNAc expression score was significantly decreased relative to MUC6 (P < 0.001). Interestingly, disease-free survival was significantly higher in MUC6-positive than MUC6-negative cases based on the log-rank test (P = 0.021). For in vitro analysis, we ectopically expressed MUC6 in A549 cells, derived from LC and harboring a KRAS mutation. MUC6-expressing A549 cells showed significantly lower proliferation, motility, and invasiveness than control cells. Finally, F-actin staining in MUC6-expressing cells revealed a decrease or loss of filopodia associated with decreased levels of FSCN transcripts, which encodes an actin-bundling protein fascin1 necessary for cell migration. We conclude that MUC6 expression is a preferable prognostic biomarker in IMA LC.

Keio Uterus Transplantation Research: From Basic Research toward Future Clinical Application.

Uterus transplantation (UTx) is now a potential option to allow women with uterine factor infertility to give birth. However, UTx is still at an experimental stage, and basic animal studies, including in non-human primates, are needed for the accumulation of data prior to clinical application. Considering that UTx may provide new hope to Japanese women, we launched UTx research in 2009 and have since accumulated a large archive of results in the UTx research field. Furthermore, we have carried out various activities aimed at the implementation of clinical applications of UTx in Japan while clarifying the ethical and social issues involved. Currently, the clinical application of UTx in Japan is just around the corner, and it is expected that UTx research will develop further in the future. Herein, we summarize our basic experiences using non-human primates and our activities with the goal of future clinical applications.

Tumor and Tumor-Associated Macrophage Programmed Death-Ligand 1 Expression Is Associated With Adjuvant Chemotherapy Benefit in Lung Adenocarcinoma.

INTRODUCTION: Patients with stage II to III lung adenocarcinomas are treated with adjuvant chemotherapy (ACT) to target the premetastatic niche that persists after curative-intent resection. We hypothesized that the premetastatic niche is a scion of resected lung tumor microenvironment and that analysis of tumor microenvironment can stratify survival benefit from ACT. METHODS: Using tumor and tumoral stroma from 475 treatment-naive patients with stage II to III lung adenocarcinomas, we constructed a tissue microarray and performed multiplex immunofluorescent staining for immune markers (programmed death-ligand 1 [PD-L1], tumor-associated macrophages [TAMs], and myeloid-derived suppressor cells) and derived myeloid-lymphoid ratio. The association between immune markers and survival was evaluated using Cox models adjusted for pathologic stage. RESULTS: Patients with high PD-L1 expression on TAMs or tumor cells in resected tumors had improved survival with ACT (TAMs: hazard ratio [HR] = 1.79, 95% confidence interval [CI]: 1.12-2.85; tumor cells: HR = 3.02, 95% CI: 1.69-5.40). Among patients with high PD-L1 expression on TAMs alone or TAMs and tumor cells, ACT survival benefit is pronounced with high myeloid-lymphoid ratio (TAMs: HR = 3.87, 95% CI: 1.79-8.37; TAMs and tumor cells: HR = 2.19, 95% CI: 1.02-4.71) or with high stromal myeloid-derived suppressor cell ratio (TAMs: HR = 2.53, 95% CI: 1.29-4.96; TAMs and tumor cells: HR = 3.21, 95% CI: 1.23-8.35). Patients with low or no PD-L1 expression on TAMs or tumor cells had no survival benefit from ACT. CONCLUSIONS: Our observation that PD-L1 expression on TAMs or tumor cells is associated with improved survival with ACT provides rationale for prospective investigation and developing chemoimmunotherapy strategies for patients with lung adenocarcinoma.

Severe bloody diarrhea due to cytokine release syndrome after chimeric antigen receptor T cell therapy for refractory acute lymphoblastic leukemia.

Cytokine release syndrome (CRS), which may be associated with fever, hypotension, hypoxia, and organ damage, is caused by a massive cytokine release after chimeric antigen receptor (CAR)-T cell therapy. We present the case of a patient who developed severe bloody diarrhea due to CRS after CAR-T cell infusion. A 10-year-old boy presented with a second relapse of B-cell precursor acute lymphoblastic leukemia 6 months after hematopoietic stem cell transplantation from an unrelated donor. CAR-T cells (tisagenlecleucel) were infused at the third complete remission after salvage chemotherapy. While fever >39°C was sustained from day 4, circulatory and respiratory status remained stable. However, he experienced severe bloody diarrhea. There was no evidence of infection; lower gastrointestinal (GI) endoscopy revealed extensive edema with erosion and ulceration, suggestive of non-specific intestinal inflammation. Thus, we considered CRS-associated grade 3 GI damage and administered a single dose of tocilizumab for grade 2 CRS, followed by 4 days of corticosteroids. Afterwards, no fever or GI bleeding was observed. Biopsy of the intestinal mucosa revealed ulcerative change with a lack of epithelial cells, which may correspond to histologic grade 4 graft versus host disease (GVHD). However, diarrhea corresponded to stage 1 GVHD, and the GVHD risk after CAR-T cell infusion has been reported to be rare in clinical practice. Although severe GI symptoms associated with CRS after CAR-T therapy are rare, early tocilizumab use is recommended for non-infectious severe GI symptoms to avoid long-term corticosteroid use, which may reduce CAR-T cell efficacy.

Standard therapy-resistant small cell lung cancer showing dynamic transition of neuroendocrine fate during the cancer trajectory: A case report.

While small cell lung cancer (SCLC) has been treated as a single disease historically, recent studies have suggested that SCLC can be classified into molecular subtypes based on the expression of lineage transcription factors such as achaete-scute homolog 1 (ASCL1), neurogenic differentiation factor 1 (NEUROD1), POU domain class 2 transcription factor 3 (POU2F3) and transcriptional coactivator YAP1 (YAP1). These transcription factor-based subtypes may be specifically targeted in therapy, and recent studies have suggested that the SCLC subtypes represent different stages of dynamic evolution of SCLC rather than independent diseases. Nevertheless, evidence of shift in neuroendocrine differentiation during SCLC evolution has been lacking in the clinical setting. In the present study, a 60-year-old male was diagnosed with extensive SCLC. The tumor responded not to the standard SCLC regimen of carboplatin, etoposide and atezolizumab, but to the non-SCLC regimen of carboplatin, nab-paclitaxel and pembrolizumab. The patient succumbed 5 months after the initial diagnosis and a pathological autopsy was performed. The tumor was originally negative for all four transcription factors, ASCL1, NEUROD1, POU2F3 and YAP1, in the biopsy specimens at diagnosis. Loss of synaptophysin expression and emergence of Myc proto-oncogene protein and YAP1 expression was recorded in the autopsy specimens, suggesting the transition to a decreased neuroendocrine fate during the disease trajectory. This case provides clinical evidence of dynamic transition of neuroendocrine fate during SCLC evolution. In light of SCLC heterogeneity and plasticity, development of precision medicine is required.

Upregulation of FGF9 in Lung Adenocarcinoma Transdifferentiation to Small Cell Lung Cancer.

Transdifferentiation of lung adenocarcinoma to small cell lung cancer (SCLC) has been reported in a subset of lung cancer cases that bear EGFR mutations. Several studies have reported the prerequisite role of TP53 and RB1 alterations in transdifferentiation. However, the mechanism underlying transdifferentiation remains understudied, and definitive additional events, the third hit, for transdifferentiation have not yet been identified. In addition, no prospective experiments provide direct evidence for transdifferentiation. In this study, we show that FGF9 upregulation plays an essential role in transdifferentiation. An integrative omics analysis of paired tumor samples from a patient with transdifferentiated SCLC exhibited robust upregulation of FGF9. Furthermore, FGF9 upregulation was confirmed at the protein level in four of six (66.7%) paired samples. FGF9 induction transformed mouse lung adenocarcinoma-derived cells to SCLC-like tumors in vivo through cell autonomous activation of the FGFR pathway. In vivo treatment of transdifferentiated SCLC-like tumors with the pan-FGFR inhibitor AZD4547 inhibited growth. In addition, FGF9 induced neuroendocrine differentiation, a pathologic characteristic of SCLC, in established human lung adenocarcinoma cells. Thus, the findings provide direct evidence for FGF9-mediated SCLC transdifferentiation and propose the FGF9-FGFR axis as a therapeutic target for transdifferentiated SCLC. SIGNIFICANCE: This study demonstrates that FGF9 plays a role in the transdifferentiation of lung adenocarcinoma to small cell lung cancer.

Cervical intramedullary recurrent Ewing sarcoma after 10-year disease-free survival in an adult: a case report and review of literature.

INTRODUCTION: Intramedullary metastasis of Ewing sarcoma is extremely rare. Here, we report an adult case of cervical intramedullary recurrent Ewing sarcoma after a 10-year disease-free survival after the initial surgery for a thoracic lesion. CASE PRESENTATION: A 39-year-old man with a history of surgery and chemoradiotherapy for thoracic Ewing sarcoma ten years ago presented with neck pain and incomplete motor paralysis in the right upper extremity, which had suddenly appeared three months before. Cervical magnetic resonance imaging revealed a tear-drop-shaped intramedullary lesion at the C3 level accompanied by diffuse edematous change. Because of the rapid progression of his myelopathy, he underwent surgery for this intramedullary lesion. Intraoperatively, the tumor exhibited an orangish exophytic appearance. The unclearness of the tumor boundary compelled us to perform a partial resection. The histopathology showed the tumor comprised small round atypical cells with immunoreactivity for Nkx2.2 and CD99, diagnosing a metastatic Ewing sarcoma. Postoperatively, although his myelopathy improved transiently and adjuvant chemotherapy radiation was undergone, he died of cranial dissemination of the tumor two months and a half later. DISCUSSION: To our knowledge, 31 cases of primary and only 4 cases of recurrent intramedullary spinal Ewing sarcoma have been reported to date; however, this is the first case of recurrent intramedullary Ewing sarcoma with a 10-year disease-free survival. Sadly, the prognosis of the current case was extremely poor. There is no clear treatment guideline for recurrent intramedullary Ewing sarcoma because of its rarity, and further collection of similar cases would be required.