The PD-1/PD-L1 Axis in HER2+ Ductal Carcinoma In Situ (DCIS) of the Breast.

OBJECTIVES: The aims were to evaluate the programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) axis in ductal carcinoma in situ (DCIS) of the breast. METHODS: We reviewed 85 pure DCIS cases treated with surgical excision at our institution, including 51 luminal A (estrogen receptor [ER] positive/human epidermal growth factor 2 [HER2] negative), 15 luminal B (ER+/HER2+), 13 HER2 (ER-/HER2+), and six basal-like (ER-/HER2-/CK5/6+). The extent and intensity of PD-1 and PD-L1 immunohistochemical staining in the tumor-infiltrating lymphocytes (TILs) and in the tumor cells were recorded. RESULTS: Our study found that moderate/severe inflammation around DCIS correlated with HER2 expression (20/28 HER2+ cases [71%] vs 21/57 HER2- cases [37%], P = .005). Of interest, over half of the TILs around the HER2 subtype expressed PD-L1 (7/13, 54%). In addition, about one-third of TILs around the HER2 subtype expressed PD-1 (4/13, 31%). CONCLUSIONS: These findings suggest that immune-based therapeutic strategies may be used as a potential therapy in DCIS cases with PD-L1 overexpression, especially those of the HER2 molecular subtype.

AngioVac extraction of intra-atrial hepatoma masquerading as PICC-associated thrombus.

Thrombus associated with peripherally inserted central catheterization is not uncommon. Treatment is typically conservative; however, more aggressive therapies can be considered in patients with tenuous medical condition. The authors present a patient with metastatic hepatocellular carcinoma masquerading as peripherally inserted central catheter-associated intra-atrial thrombus, subsequently removed via vacuum-assisted mechanical thrombectomy.

Two Subtypes of Atypical Leiomyoma: Clinical, Histologic, and Molecular Analysis.

Atypical leiomyoma (ALM) is a rare variant of uterine smooth muscle tumors. Several recent studies have suggested that ALM has distinct, but also heterogenous, histologic and molecular features, yet little is known about the biology and histogenesis of ALM. Some have even postulated whether the atypical histologic features represent true atypia or simply degenerative changes. In this study, we analyzed the cytologic features of 60 ALM cases and found that ALM could be further divided into 2 subtypes, type I and type II, based primarily on nuclear features. Type I ALM showed round or oval nuclei, distinct and smooth nuclear membranes, prominent nucleoli with perinucleolar halos, and open coarse chromatin. Type II ALM showed elongated or spindled nuclei, irregular nuclear membranes, pinpoint or no nucleoli, and dark smudgy chromatin. There were also architectural differences between type I and type II ALM. Type I ALM often showed diffuse atypia within the tumor, whereas the atypia in type II ALM was patchy, surrounded by usual-type leiomyoma. The 2 subtypes also differed when we compared the immunohistochemical and molecular patterns. Type II tumors showed significantly higher rates of immunoreactivity for p16, p53, and HMGA2 and showed MED12 mutations more frequently than the type I counterparts. Our findings suggest that the type I and type II subtypes of ALM may arise from 2 different pathways. Type I tumors may be related to fumarate hydratase mutations, whereas type II ALM appear to arise in a existing usual-type leiomyomas.