In a substantial number of patients, ductal carcinoma in situ (DCIS) of the breast will never progress to invasive ductal carcinoma, and these patients are often overtreated under the current clinical criteria. Although various candidate markers are available, relevant markers for delineating risk categories have not yet been established. In this study, we analyzed the clinical characteristics of 431 patients with DCIS and performed whole-exome sequencing analysis in a 21-patient discovery cohort and targeted deep sequencing analysis in a 72-patient validation cohort. We determined that age <45 years, HER2 amplification, and GATA3 mutation are possible indicators of relapse. PIK3CA mutation negativity and PgR negativity were also suggested to be risk factors. Spatial transcriptome analysis further revealed that GATA3 dysfunction upregulates epithelial-to-mesenchymal transition and angiogenesis, followed by PgR downregulation. These results reveal the existence of heterogeneous cell populations in DCIS and provide predictive markers for classifying DCIS and optimizing treatment.

Background: In this study we aimed to clarify the PD-L1 positive expression in lung adenocarcinoma, including various adenocarcinoma subtypes paying particular attention to its component. Methods: A total of 307 lung adenocarcinoma patients who underwent lobectomy or segmentectomy, as well as systematic lymph node dissection (ND2a), from February 2008 to March 2020 at our hospital, were enrolled into the study. A final diagnosis of adenocarcinoma was obtained from the resected lung specimens of all 307 patients to determine the histological type, adenocarcinoma subtype, and component of adenocarcinoma by ethics of 5%. PD-L1 was immunohistochemically stained using the murine monoclonal antibody clone 22C3. Results: When PD-L1 expression-positive was defined by tumor proportion score (TPS) ≥1%, the positive cases were 6/33 in adenocarcinoma (Ad) in situ (AIS), 2/26 in minimally invasive Ad (MIA), 12/60 in lepidic predominant Ad (LPA), 44/91 in papillary predominant Ad (PPA), 24/49 in acinar predominant Ad (APA), 23/28 in solid predominant Ad (SPA), 4/7 in micropapillary predominant Ad (MPA), and 0/13 in invasive mucinous Ad (IMA). In the high proportion group (APA, PPA, SPA, and MPA) of PD-L1 expression, SPA was the only subtype which was statistically significant when both PD-L1 expression-positive was defined by TPS ≥ 1% (p < 0.0001) and TPS ≧ 50% (p < 0.0001). We then considered the solid component. We investigated 279 cases of the other subtype group excluding SPA. The group containing a solid component (≥5%) tended to be PD-L1 expression-positive both when defined by TPS ≥1% (p < 0.0001) and TPS ≧50% (p = 0.0049). Conclusions: The PD-L1 expression tended to be positive when a solid component was confirmed (≥5%) in specimens of lung adenocarcinoma patients.

Here, cases of a 68-(Case 1) and a 44-year-old (Case 2) female are presented. They had an abnormality in the breast, and came to our hospital for further examination and treatment. Radiologically, malignancy could not completely excluded so breast excision was performed. Histologically, both cases revealed papillary neoplastic lesions lined by fibrovascular core and nuclear inverse polarity without atypia. Loss of myoepithelial cells was observed by HE, p63, and calponin. Previous report indicate CK5/6, ER, p63 and MUC3 are important for distinguishing between papillary lesions according to the differential index (based on Allred score) of ([ER total score] þ [MUC3 total score])/([CK5/6 total score] þ [p63 total score] þ 1). Based on this analysis, our two cases had benign lesions. However, based on immunopositivity for cell-cycle marker Cyclin-D1, Case 1 was negative, and Case 2 was about 70% positive. Additionally, the Ki-67 index was <1% in both cases, and no evidence of disease was observed after a maximum 62 months of follow-up in both cases, despite lack of additional treatment. Thus, we propose that lack of myoepithelial cells in papillary lesions do not necessarily indicate malignancy and are thought to be, at the most, uncertain malignant potential.

There are few prospective reports of transbronchial lung cryobiopsy (TBLC) for malignant tumors in combination with forceps biopsy. We investigated the clinical parameters in which TBLC is superior to forceps biopsy. This is a prospective cohort study to analyse the efficacy of TBLC for suspected malignancy. TBLC was performed after brushing cytology and forceps biopsy, and the diagnostic yield for TBLC, brushing cytology, and forceps biopsy were examined. Adverse events were defined as those requiring additional procedures. Next-generation sequencing (NGS) analysis was performed in each case of non-small cell lung cancer. Of the 100 patients, malignancy was confirmed in 94 cases. The diagnostic yield for TBLC/forceps biopsy/brushing cytology was 86/81/82% respectively, while the diagnostic yield for all procedures combined was 94%. There was no significant difference in the diagnostic yield between TBLC and forceps biopsy. When comparing the biopsy site, the diagnostic yield for TBLC at the lower lobe was significantly higher than forceps biopsy (P < 0.01). Endobronchial ultrasonography imaging using a guide-sheath did not significantly differ in the diagnostic yield of TBLC. The success rate of NGS for TBLC specimens was 100% (26 cases). Adverse events included two cases of severe bleeding. TBLC of peripheral lesions may improve the diagnostic yield when combined with forceps biopsy and brushing cytology. The diagnostic yield of TBLC was higher at the lower lobes. Furthermore, TBLC provided sufficient specimen quality for NGS.

A substantial number of cases of ductal carcinoma in situ (DCIS) of the breast will never progress to invasive ductal carcinoma (IDC), indicating they are overtreated under the current criteria. Although various candidate markers are available, the relevant markers for delineating the risk categories have not been established. In this study, we analyzed of the integrated clinical features of 431 cases of DCIS followed by deep sequence analyses in a 21-case discovery cohort and a 72-case validation cohort. We identified the five most critical markers of the aggressiveness of DCIS: age <45 years, HER2 amplification, GATA3 mutation positivity, PIK3CA mutation negativity, and PgR protein negativity. Spatial transcriptome and single-cell DNA sequencing further revealed that GATA3 dysfunction, but not PIK3CA mutation, upregulates EMT, invasion, and angiogenic pathways followed by PgR downregulation. These results reveal the existence of heterogeneous populations of DCIS and provide predictive markers for classifying DCIS and optimizing treatment.