Stromal tumor-infiltrating lymphocytes (sTILs) are important prognostic and predictive biomarkers in triple-negative (TNBC) and HER2-positive breast cancer. Incorporating sTILs into clinical practice necessitates reproducible assessment. Previously developed standardized scoring guidelines have been widely embraced by the clinical and research communities. We evaluated sources of variability in sTIL assessment by pathologists in three previous sTIL ring studies. We identify common challenges and evaluate impact of discrepancies on outcome estimates in early TNBC using a newly-developed prognostic tool. Discordant sTIL assessment is driven by heterogeneity in lymphocyte distribution. Additional factors include: technical slide-related issues; scoring outside the tumor boundary; tumors with minimal assessable stroma; including lymphocytes associated with other structures; and including other inflammatory cells. Small variations in sTIL assessment modestly alter risk estimation in early TNBC but have the potential to affect treatment selection if cutpoints are employed. Scoring and averaging multiple areas, as well as use of reference images, improve consistency of sTIL evaluation. Moreover, to assist in avoiding the pitfalls identified in this analysis, we developed an educational resource available at www.tilsinbreastcancer.org/pitfalls.

The advent of immune-checkpoint inhibitors (ICI) in modern oncology has significantly improved survival in several cancer settings. A subgroup of women with breast cancer (BC) has immunogenic infiltration of lymphocytes with expression of programmed death-ligand 1 (PD-L1). These patients may potentially benefit from ICI targeting the programmed death 1 (PD-1)/PD-L1 signaling axis. The use of tumor-infiltrating lymphocytes (TILs) as predictive and prognostic biomarkers has been under intense examination. Emerging data suggest that TILs are associated with response to both cytotoxic treatments and immunotherapy, particularly for patients with triple-negative BC. In this review from The International Immuno-Oncology Biomarker Working Group, we discuss (a) the biological understanding of TILs, (b) their analytical and clinical validity and efforts toward the clinical utility in BC, and (c) the current status of PD-L1 and TIL testing across different continents, including experiences from low-to-middle-income countries, incorporating also the view of a patient advocate. This information will help set the stage for future approaches to optimize the understanding and clinical utilization of TIL analysis in patients with BC.

Occlusion of saphenous vein grafts is a major problem after coronary artery bypass grafting. Segments of occluded and suboccluded implanted aortocoronary grafts were obtained during re-intervention bypass grafting in 47 patients yielding a total of 80 vein grafts. The grafts were studied by immunohistochemistry for smooth muscle cells (alpha-SMC actin), macrophages (HAM56), cell replication (PCNA, Ki-67) and transmission and scanning electronmicroscopy (TEM, SEM). In 81% of the examined grafts the (sub)occlusion was due to a myo-intimal thickening and an associated luminal accumulation of foam cells and mural thrombi. The foam cells were constantly found at the luminal site of the myo-intimal thickening and within the luminal part of adherent thrombi. Transmission electronmicroscopy demonstrated phagocytosis of platelets and platelet fragments by the foam cells. A significant fraction of the foam cells demonstrated nuclear immunoreactivity for Ki-67 and PCNA. The myo-intimal thickening of the vein grafts was composed of smooth muscle cells lying in a fibrous tissue matrix. The smooth muscle cells were surrounded by prominent basal lamina and showed ultrastructural features of apoptosis. Our results support the hypothesis that phagocytosis of lipid rich platelets by monocytes set up a mechanism for foam cell formation and replication in human saphenous vein grafts. The transformation of a smooth muscle cell rich myointimal thickening towards a fibrous, cell poor intimal thickening could be induced by progressive smooth muscle cell loss through apoptosis.

BackgroundPediatric germ cell tumors account for approximately 3.5 % of all childhood cancers for children under the age of 15 years. Up to one-third are extragonadal neoplasms. Germ cell tumors are a heterogeneous group of malignant tumors with a wide variety of histopathological features. Yolk sac tumor is the predominant variant in newborns and younger children. We report for the first time, the presentation of a primary yolk sac tumor in the abdominal wall of a small child.Case presentationAn 18-month-old white girl underwent resection of a small, round subcutaneous lump (1.5×1.3×0.8 cm) of the abdominal wall in her right hypochondriac region. The histopathology was compatible with yolk sac tumor. Her alpha-fetoprotein was initially elevated but normalized after the resection. Magnetic resonance imaging of her abdomen was normal. The surgeon decided to observe and follow her alpha-fetoprotein level closely. One year after resection a local recurrence appeared and her alpha-fetoprotein rose to 58 ng/mL. The surgeon performed a wide resection of the lesion with normalization of her alpha-fetoprotein. Follow-up consisted of measuring alpha-fetoprotein, clinical evaluation, and abdominal ultrasound.ConclusionsClinicians should be aware that a yolk sac tumor can present in an unusual extragonadal place, for example in this case it was subcutaneous. In some cases, conservative treatment can be carried out with careful monitoring of the patient and their alpha-fetoprotein.