Features Of Tumors Research Articles

Diagnostic Approach to Mesenchymal and Spindle Cell Tumors of the Breast

Mesenchymal and spindle cell tumors of the breast represent a broad and heterogeneous group of lesions that may be sampled on core needle biopsy or surgical excision. Mesenchymal lesions unique to the breast are those that derive from the specialized breast myofibroblast, such as mammary myofibroblastoma and pseudoangiomatous stromal hyperplasia. However, any mesenchymal lesion arising in extramammary soft tissue may also arise in the breast, including fibroblastic, peripheral nerve sheath, adipocytic, and vascular lesions. The spindle cell lesions pose the greatest diagnostic challenge, due to the significant radiographic, morphologic, and immunophenotypic overlap within the category of mesenchymal lesions and more broadly with other nonmesenchymal breast lesions. The distinction is particularly challenging on the limited material of breast core needle biopsies, and caution should be taken before definitively classifying a breast spindle cell lesion on core needle biopsy to avoid unnecessary treatment if misdiagnosed. Consideration of a wide differential diagnosis, adequate sampling of a resection specimen, use of a targeted immunopanel, and selective use of molecular assays are essential steps for accurate classification of mesenchymal lesions in the breast. This review covers the clinical, histologic, and immunophenotypic features of mesenchymal tumors of the breast, with a special emphasis on the differential diagnoses unique to the breast and challenges encountered on breast core needle biopsy.

Clinical Predilection Features of Middle Ear Adenomatous Neuroendocrine Tumors: A Review of 10 Patients and a Special Case Is Attached.

Introduction: Middle ear adenomatous neuroendocrine tumors (MEANTs) are rare middle ear lesions characterized by nonspecific symptoms, signs, and imaging findings. Diagnosis typically relies on postoperative pathological assessment. This study investigated the diagnostic utility of the predilection sites and clinical characteristics of MEANTs. Methods: A retrospective analysis was conducted on clinical data from 10 patients with histologically confirmed MEANTs, admitted to Eye & ENT Hospital of Fudan University between March 2016 and March 2023. Results: The median age of the patients at diagnosis was 39.3 years. Hearing loss (n = 8) and ear pain (n = 6) were the most prevalent clinical symptoms in the patients diagnosed with MEANTs. Endoscopic examination revealed diverse symptoms, predominantly presenting as non-pulsatile masses with distinct boundaries and quasi-circular shapes within the external auditory canal, often accompanied by abundant blood vessels (n = 4). Tumors were typically confined to the middle/lower tympanic chambers or eustachian tube and were frequently associated with tympanic sclerosis, particularly around the pharyngeal tube (n = 3). Pathologically, MEANTs exhibited CD56 positivity or weak positivity, along with positive staining for CKpan and Syn, negativity for S100, and Ki67 ≤3%. Personalized surgical interventions were chosen by all the patients based on lesion severity, with no subsequent radiotherapy or chemotherapy administered postoperatively. No tumor progression was noted during the postoperative follow-up. In addition, a noteworthy case was presented in which MEANT initially manifested in the middle or lower tympanic cavity and eustachian tubes. Over 2 years, the tumor progressively grew, invading the middle tympanum and surrounding ossicles, ultimately achieving complete resection with no recurrence observed during subsequent follow-up. Conclusions: A possible diagnosis of middle ear adenoma should be considered when encountering non-pulsatile tumors with clearly demarcated inner boundaries within the external auditory canal accompanied by abundant quasi-circular vessels and the presence of new bone or neoplasm at the pharyngeal tympanic canal orifice observed during preoperative examinations or surgical procedures.

Epidemiological Features of 4777 Cysts and Odontogenic Tumors Based on the 2022 WHO Classification.

The epidemiology of cysts and odontogenic tumors is important for differential diagnosis and treatment strategies. We aimed to describe the epidemiological features of cysts and odontogenic tumors in the Chilean population using the current WHO classification. We reviewed 22,914 biopsy requests received between January 1984 and September 2023 at the oral pathology department, School of Dentistry, Universidad Mayor, Santiago, Chile. Patients diagnosed with cysts of the jaws and odontogenic tumors were selected and information regarding age, sex, and location was recorded. 4226 (18.4%) were cysts, and 551 (2.4%) were odontogenic tumors, ranging from 2 to 97 years old. Males represented 54.4% and females 45.7% of the total sample. The most prevalent cysts were radicular cysts (58.6%), dentigerous cysts (17.9%), and odontogenic keratocysts (13.3%). The most prevalent odontogenic tumors were odontomas (40.1%) and conventional ameloblastoma (17.6%). Our study was the first retrospective analysis to determine the epidemiological features of both cysts and odontogenic tumors together, based on the 2022 WHO classification. This is relevant as it offers a potential basis for comprehensive comparisons of the epidemiological features of these entities, which could contribute to an accurate differential diagnosis, therefore, leading to more effective therapeutic interventions.

Cellular liquid biopsy provides unique chances for disease monitoring, preclinical model generation and therapy adjustment in rare salivary gland cancer patients.

While cell-free liquid biopsy (cfLB) approaches provide simple and inexpensive disease monitoring, cell-based liquid biopsy (cLB) may enable additional molecular genetic assessment of systemic disease heterogeneity and preclinical model development. We investigated 71 blood samples of 62 patients with various advanced cancer types and subjected enriched circulating tumor cells (CTCs) to organoid culture conditions. CTC-derived tumoroid models were characterized by DNA/RNA sequencing and immunohistochemistry, as well as functional drug testing. Results were linked to molecular features of primary tumors, metastases, and CTCs; CTC enumeration was linked to disease progression. Of 52 samples with positive CTC counts (≥1) from eight different cancer types, only CTCs from two salivary gland cancer (SGC) patients formed tumoroid cultures (P = 0.0005). Longitudinal CTC enumeration of one SGC patient closely reflected disease progression during treatment and revealed metastatic relapse earlier than clinical imaging. Multiomics analysis and functional invitro drug testing identified potential resistance mechanisms and drug vulnerabilities. We conclude that cLB might add a functional dimension (to the genetic approaches) in the personalized management of rare, difficult-to-treat cancers such as SGC.

Epidemiology and tumor microenvironment of ocular surface and orbital tumors on growth and malignant transformation.

The ocular surface and orbit constitute unique microenvironments in the human body. Current advances in molecular research have deepened our understanding of tumor development in these regions. Tumors exhibit greater heterogeneity compared to normal tissues, as revealed by pathological and histological examinations. The tumor microenvironment (TME) plays a crucial role in the proliferation and progression of cancer cells. Factors from the external environment or the body's own inflammation and microcirculation interact within the TME, maintaining a delicate balance. Disruption of this balance, through uncontrolled signal pathway activation, can transform normal or benign tissues into malignant ones. In recent years, various systemic immunotherapies have been developed for cancer treatment. This study reviews the epidemiology of ocular surface and orbital tumors include squamous cell carcinoma, basal cell carcinoma, sebaceous carcinoma and lymphoma in conjunction with their occurrence, growth, and underlying mechanisms. We propose that by examining clinical histopathological images, we can identify specific and shared microscopic features of tumors. By collecting, classifying, and analyzing data from these clinical histopathological images, we can pinpoint independent diagnostic factors characteristic of tumors. We hope this study provides a basis for future exploration of the mechanisms underlying different ocular diseases.

Histopathological features of subcutaneous and cutaneous mast cell tumors in dogs

BackgroundMast cell tumors (MCTs) are the most common malignant skin neoplasms in dogs. In the past, the distinction between cutaneous MCTs (cMCTs), originating from the dermis, and subcutaneous MCTs (scMCTs), originating from the subcutaneous tissue, was not made. Histopathological differentiation, including grading, is important for prognosis. However, the Patnaik and Kiupel grading systems were proposed for cMCTs only. The objective of our study was to describe and compare the signalment of dogs with scMCTs and cMCTs and histopathological features, anticipating similarities in both groups. Data of dogs histologically diagnosed with scMCTs or cMCTs between September 2020 and July 2023 were analyzed retrospectively. Signalment, tumor location, histopathological features, completeness of removal and lymph node status were recorded.ResultsData on 305 scMCTs and 1291 cMCTs were collected. Breed distribution was different between scMCTs and cMCTs (P < 0.0001). Mitotic count (MC) was not different between scMCTs (1.63) and cMCTs (1.58) (P = 0.8490). Compared to cMCTs, scMCTs more often had anisokaryosis, bizarre nuclei and multinucleation. Kiupel high grade was more often assigned to scMCTs (51/292, 17.5%) than cMCTs (154/1291, 11.9%) (P = 0.009). The odds of MCTs being assigned a high grade in scMCT was 1.578 higher than in cMCTs (95% confidence interval [1.116–2.232]).ConclusionsHistopathological differences between scMCTs and cMCTs were observed. A Kiupel high grade was more often assigned to scMCTs than cMCTs. Whether these histopathological findings correlate with clinical outcome has to be established in additional studies.

Comparison of clinicopathological characteristics, efficacy of neoadjuvant therapy, and prognosis in HER2-low and HER2-ultralow breast cancer

BackgroundThis study aims to analyze potential differences in clinicopathology, efficacy of neoadjuvant therapy (NAT), and clinical outcome among HER2-null, HER2-ultralow and HER2-low breast cancers.MethodsConsecutive cases of HER2-negative breast cancer that received NAT were included. They were classified as HER2-null (no staining), HER2-ultralow (incomplete faint staining in ≤ 10% of tumour cells) and HER2-low (HER2-1 + or HER2-2+, in situ hybridisation negative). Subgroup analysis was performed based on the HER2 expression level.ResultsOut of 302 patients, 215 (71.19%) were HER2-low, 59 (19.54%) were HER2-ultralow, and 28 (9.27%) were HER2-null. In comparison to the HER2-ultralow group, the HER2-low group exhibited higher expression frequencies of ER (p < 0.001), PR (p < 0.001), and AR (p = 0.004), along with a greater prevalence of the luminal subtype (p < 0.001). The HER2-ultralow group also demonstrated a higher prevalence of lymph node metastasis compared to the HER2-null group (p = 0.026). Varied rates of pathologic complete response (pCR) were observed among the three subgroups: HER2-null, HER2-ultralow, and HER2-low, with rates of 35.71%, 22.03%, and 12.56%, respectively. Only the HER2-low subgroup exhibited a significant difference compared to HER2-null (p = 0.001). Despite variations in pCR rates, the three subgroups exhibited comparable disease-free survival (DFS) (p = 0.571). Importantly, we found HER2-low patients with better treatment response (RCB-0/I) exhibited significantly better DFS than those with significant residual disease (RCB-II/III) (P = 0.036). The overall rate of HER2 immunohistochemical score discordance was 45.24%, mostly driven by the conversion between HER2-0 and HER2-low phenotype. Notably, 32.19% of cases initially classified as HER2-0 phenotype on baseline biopsy were later reclassified as HER2-low after neoadjuvant therapy, and it is noteworthy that 22 out of these cases (78.57%) originally had an HER2-ultralow status in the pretreatment biopsy sample.ConclusionsOur results demonstrate the distinct clinicopathological features of HER2-low and HER2-ultralow breast tumors and confirm that RCB is an effective predictor of prognosis in HER2-low populations for the first time. Notably, our findings demonstrate high instability in both HER2-low and HER2-ultralow expression from the primary baseline biopsy to residual disease after NAT. Furthermore, this study is the first to investigate the clinicopathological feature and the effectiveness of NAT for HER2-ultralow breast cancer.

Single-cell and spatial omics unravel the spatiotemporal biology of tumour border invasion and haematogenous metastasis.

Solid tumours exhibit a well-defined architecture, comprising a differentiated core and a dynamic border that interfaces with the surrounding tissue. This border, characterised by distinct cellular morphology and molecular composition, serves as a critical determinant of the tumour's invasive behaviour. Notably, the invasive border of the primary tumour represents the principal site for intravasation of metastatic cells. These cells, known as circulating tumour cells (CTCs), function as 'seeds' for distant dissemination and display remarkable heterogeneity. Advancements in spatial sequencing technology are progressively unveiling the spatial biological features of tumours. However, systematic investigations specifically targeting the characteristics of the tumour border remain scarce. In this comprehensive review, we illuminate key biological insights along the tumour body-border-haematogenous metastasis axis over the past five years. We delineate the distinctive landscape of tumour invasion boundaries and delve into the intricate heterogeneity and phenotype of CTCs, which orchestrate haematogenous metastasis. These insights have the potential to explain the basis of tumour invasion and distant metastasis, offering new perspectives for the development of more complex and precise clinical interventions and treatments.

Posterior pituitary tumors and other rare entities involving the pituitary gland.

Non-neuroendocrine tumors account for around 10% of all primary neoplasms of the sella. If meningiomas, craniopharyngiomas, and germ cell tumors are excluded, the remaining lesions include a broad spectrum of uncommon, benign, and aggressive, often diagnostically challenging lesions. This review aims to summarize the essential clinicopathological features of tumors of the posterior pituitary gland, infundibulum spectrum expressing thyroid transcription factor 1, and primary sellar atypical rhabdoid teratoid tumor, and provide the criteria for their diagnosis and management.

Computed tomography radiomics models of tumor differentiation in canine small intestinal tumors.

Radiomics models have been widely exploited in oncology for the investigation of tumor classification, as well as for predicting tumor response to treatment and genomic sequence; however, their performance in veterinary gastrointestinal tumors remains unexplored. Here, we sought to investigate and compare the performance of radiomics models in various settings for differentiating among canine small intestinal adenocarcinoma, lymphoma, and spindle cell sarcoma. Forty-two small intestinal tumors were contoured using four different segmentation methods: pre- or post-contrast, each with or without the inclusion of intraluminal gas. The mesenteric lymph nodes of pre- and post-contrast images were also contoured. The bin settings included bin count and bin width of 16, 32, 64, 128, and 256. Multinomial logistic regression, random forest, and support vector machine models were used to construct radiomics models. Using features from both primary tumors and lymph nodes showed significantly better performance than modeling using only the radiomics features of primary tumors, which indicated that the inclusion of mesenteric lymph nodes aids model performance. The support vector machine model exhibited significantly superior performance compared with the multinomial logistic regression and random forest models. Combining radiologic findings with radiomics features improved performance compared to using only radiomics features, highlighting the importance of radiologic findings in model building. A support vector machine model consisting of radiologic findings, primary tumors, and lymph node radiomics features with bin count 16 in post-contrast images with the exclusion of intraluminal gas showed the best performance among the various models tested. In conclusion, this study suggests that mesenteric lymph node segmentation and radiological findings should be integrated to build a potent radiomics model capable of differentiating among small intestinal tumors.

Role of Fine Needle Aspiration Cytology in Paratesticular Neoplasms-A Case Reports-Based Systematic Review.

The cytology features of neoplastic paratesticular lesions are mostly documented as case reports. Thus, we conducted a case report-based literature review to identify the characteristics of paratesticular neoplasms and tried to determine the significance of FNAC in these tumors. The studies were searched using PubMed and Scopus. The quality assessment was done using the JBI critical appraisal checklist for case reports. The articles that received an overall rating of "Include" underwent data extraction. The data were extracted from the articles and analyzed. We included 34 case reports from 33 published articles. The mean age of patients was 44.74 (13-85) years, and the most common clinical manifestation was scrotal swelling (70.59%, 24/34). Lesions were commonly observed on the right side (65.63%, 21/32), and the most common tumor site was epididymis (35.29%, 12/34). A total of 38.24% (13/34) cases were nonmalignant, and 61.76% (21/34) were malignant on the cytological diagnosis. The adenomatoid tumor (53.85, 7/13) was the most common nonmalignant tumor. Other entities were schwannoma, benign spindle cell neoplasm with atypia, nerve sheath tumor, lipoma, undifferentiated pleomorphic sarcoma, rhabdomyosarcoma, epithelioid sarcoma, liposarcoma, malignant rhabdoid tumor, pigmented neuroectodermal tumor of infancy and mesothelioma. Considering the malignant and nonmalignant groups, the sensitivity, specificity, and diagnostic accuracy of cytology were 95.00%, 84.62%, and 90.91%, respectively. Cytopathologists should be familiar with the cytological features of various malignant and nonmalignant paratesticular tumors to prevent unnecessarily invasive surgical management. The current systematic review emphasizes usefulness of FNAC in the preoperative cytological identification of paratesticular tumors.

A novel computational pathology approach for identifying gene signatures prognostic of disease-free survival for papillary thyroid carcinomas

IntroductionPapillary thyroid carcinoma (PTC) is the most prevalent form of thyroid cancer, with the classical and follicular variants representing most cases. Despite generally favorable prognoses, approximately 10% of patients experience recurrence post-surgery and radioactive iodine therapy. Attempts to stratify risk of recurrence have relied on gene expression-based prognostic and predictive signatures with a focus on mutations of well-known driver genes, while hallmarks of tumor morphology have been ignored. ObjectivesWe introduce a new computational pathology approach to develop prognostic gene signatures for PTC that is informed by quantitative features of tumor and immune cell morphology. MethodsWe quantified nuclear and immune-related features of tumor morphology to develop a pathomic signature, which was then used to inform an RNA-expression signature model provides a notable advancement in risk stratification compared to both standalone and pathology-informed gene-expression signatures. ResultsThere was a 17.8% improvement in the C-index (from 0.605 to 0.783) for 123 cPTCs and 15% (from 0.576 to 0.726) for 38 fvPTCs compared to the standalone gene-expression signature. Hazard ratios also improved for cPTCs from 0.89 (0.67,0.99) to 4.43 (3.65,6.68) and fvPTC from 0.98 (0.76,1.32) to 2.28 (1.87,3.64). We validated the image-based risk model on an independent cohort of 32 cPTCs with hazard ratio 1.8 (1.534,2.167).

Establishment and characterization of a novel human gallbladder cancer cell line, GBC-X1

In this study, we successfully established a novel gallbladder cancer cell line, designated as GBC-X1, derived from a primary tumor of a gallbladder cancer patient. By comprehensively analyzing the cell line’s phenotype, molecular characteristics, biomarkers, and histological characteristics, we confirmed that GBC-X1 serves as a valuable model for investigating the pathogenesis of gallbladder cancer and developing therapeutic agents. GBC-X1 has been continuously cultured for one year, with over 60 stable passages. Morphologically, GBC-X1 exhibits typical features of epithelial tumors. The population doubling time of GBC-X1 is 32 h. STR analysis validated a high consistency between GBC-X1 and the patient’s primary tumor. Karyotype analysis revealed an abnormal hypertetraploid karyotype for GBC-X1, characterized by representative karyotypes of 98, XXXX del (4) p (12) del (5) p (21) der (10). Under suspension culture conditions, GBC-X1 efficiently forms tumor balls, while subcutaneous inoculation of GBC-X1 cells into NXG mice leads to xenograft formation with a rate of 80%. Drug sensitivity testing demonstrated that GBC-X1 is resistant to oxaliplatin and sensitive to 5-FU, gemcitabine, and paclitaxel. Immunohistochemistry revealed positive expression of CK7, CK19, E-cadherin, MMP-2, CD44, SOX2, and TP53 in GBC-X1 cells, weak positive expression of Vimentin, and a Ki67 positive rate of 35%. Our research highlights GBC-X1 as a novel gallbladder cancer cell line and emphasizes its potential as an effective experimental model for investigating the pathogenesis of gallbladder cancer and drug development.

Histopathological spectrum of ovarian tumours

Background: Ovarian neoplasms include wide spectrum of various tumors, which differ in their histo-morphological features, also in their biological behaviour, tumorigenesis, clinical course, and prognosis. Aim of the study was to study the histopathological features of various ovarian tumors and correlate preoperative serum CA125 tumor marker level with histopathological types. Also to study fallopian tubes for fallopian tube precursor lesions such as serous tubal intraepithelial carcinoma (STIC) in serous carcinoma ovary. Methods: This cross-sectional observational study of the 80 specimens of ovarian tumors was conducted in department of pathology, Netaji Subhash Chandra Bose medical college Jabalpur (M.P.). The relevant data of the patients was collected and analysed as per designed proforma. Results: Out of 80 cases; majority cases 22 (27.5%) were seen in a 31-40 years age group, followed by 41-50 years age group 18 cases (22.5%). Youngest patient was 7 years old and oldest patient was 88 years old, forming the range of 7 years to 88 years. Epithelial tumors were the most common category, followed by germ cell tumors, sex cord stromal tumors and metastatic tumors. Benign tumors were much higher than borderline and malignant tumors mature cystic teratoma was the most common tumor encountered, followed by mucinous cystadenoma. The commonest malignant tumor was serous carcinoma followed by mucinous carcinoma. Conclusions: Ovarian neoplasms constitute a wide spectrum of tumors therefore exact categorization is important to adopt appropriate treatment protocols for the proper management of the patient. Histopathological examination is the gold standard for diagnosis and categorization of ovarian neoplasm.

Multi-regional genomic and transcriptomic characterization of a melanoma-associated oral cavity cancer provide evidence for CASP8 alteration-mediated field cancerization

BackgroundPrecancerous and malignant tumours arise within the oral cavity from a predisposed “field” of epithelial cells upon exposure to carcinogenic stimulus. This phenomenon is known as “Field Cancerization”. The molecular genomic and transcriptomic alterations that lead to field cancerization and tumour progression is unknown in Indian Oral squamous cell carcinoma (OSCC) patients.MethodsWe have performed whole exome sequencing, copy-number variation array and whole transcriptome sequencing from five tumours and dysplastic lesions (sampled from distinct anatomical subsites - one each from buccal anterior and posterior alveolus, dorsum of tongue–mucosal melanoma, lip and left buccal mucosa) and blood from a rare OSCC patient with field cancerization.ResultsA missense CASP8 gene mutation (p.S375F) was observed to be the initiating event in oral tumour field development. APOBEC mutation signatures, arm-level copy number alterations, depletion of CD8 + T cells and activated NK cells and enrichment of pro-inflammatory mast cells were features of early-originating tumours. Pharmacological inhibition of CASP8 protein in a CASP8-wild type OSCC cell line showed enhanced levels of cellular migration and viability.ConclusionCASP8 alterations are the earliest driving events in oral field carcinogenesis, whereas additional somatic mutational, copy number and transcriptomic alterations ultimately lead to OSCC tumour formation and progression.

Brain tumor image segmentation method using hybrid attention module and improved mask RCNN

To meet the needs of automated medical analysis of brain tumor magnetic resonance imaging, this study introduces an enhanced instance segmentation method built upon mask region-based convolutional neural network. By incorporating squeeze-and-excitation networks, a channel attention mechanism, and concatenated attention neural network, a spatial attention mechanism, the model can more adeptly focus on the critical regions and finer details of brain tumors. Residual network-50 combined attention module and feature pyramid network as the backbone network to effectively capture multi-scale characteristics of brain tumors. At the same time, the region proposal network and region of interest align technology were used to ensure that the segmentation area matched the actual tumor morphology. The originality of the research lies in the deep residual network that combines attention mechanism with feature pyramid network to replace the backbone based on mask region convolutional neural network, achieving an improvement in the efficiency of brain tumor feature extraction. After a series of experiments, the precision of the model is 90.72%, which is 0.76% higher than that of the original model. Recall was 91.68%, an increase of 0.95%; Mean Intersection over Union was 94.56%, an increase of 1.39%. This method achieves precise segmentation of brain tumor magnetic resonance imaging, and doctors can easily and accurately locate the tumor area through the segmentation results, thereby quickly measuring the diameter, area, and other information of the tumor, providing doctors with more comprehensive diagnostic information.

The CT and pathological features of intestinal inflammatory myofibroblastic tumor

AbstractTo explore computed tomography (CT) findings and pathological features of intestinal inflammatory myofibroblastic tumors (IMT). A retrospective review was conducted on the CT features of five patients with pathologically confirmed IMT, which were then compared with the corresponding pathological findings. The study included four female and one male patients. The tumors were located in the rectum (n = 1), small intestine (n = 2), or cecum (n = 2). One patient exhibited a cystic solid mass with exophytic growth and the solid components showed moderate enhancement. Additionally, flaky low‐density, marginal line‐like calcified shadows were observed around the lesions. Two cases presented as solid masses within the lumen of the intestinal tract, showing obvious non‐uniform enhancement along with visible enhancement shadows of small blood vessels. One patient had a metastasis. In two other cases, solid masses grew outside the lumen of the intestinal tract, demonstrating progressive and delayed enhancement on enhanced scans, as well as local nodular enhancement and ring enhancement. These two cases also exhibited focal sarcomatoid lesions, along with their respective IMTs. Histologically, these tumors mainly consist of proliferating spindle myofibroblast cells accompanied by variable infiltration by interstitial inflammatory cells, such as fibroblasts. Immunohistochemical analysis revealed positive staining for smooth muscle actin (SMA) in ~80% of the cells tested, while vimentin staining was positive in ~60% of the cells. Intestinal IMT is an extremely rare tumor with imaging features that can reflect the underlying pathological characteristics to some extent, thus aiding diagnosis.

Cytological features of ependymal and choroid plexus tumours.

Ependymal and choroid plexus tumours arise in anatomically related regions. Their intraoperative differential diagnosis is large and depends on factors such as age, tumour site and clinical presentation. Squash cytology can provide valuable information in this context. Cytological features of conventional ependymomas, subependymomas and myxopapillary ependymomas as well as choroid plexus tumours are reviewed and illustrated. Differential diagnostic considerations integrating morphological and clinical information are discussed.

Clinical and pathological features of renal tumours among women previously treated for breast carcinomas – the CanSeRe study

IntroductionRenal cell carcinoma (RCC) and breast carcinoma (BC) are frequent tumours, yet their co-occurrence in the same patient is a unique scenario. Few studies explored the characteristics of such patients without specific focus on pathological data. In this retrospective study, we aimed to describe the clinico-pathological features of RCC patients with a history of BC and compare them to a control cohort of RCC women free of previous BC. MethodsAll adult women treated for BC at a high-volume cancer institution between 2007 and 2020 and who subsequently developed a RCC were retrospectively included. Their clinical and pathological characteristics were compared to an independent cohort of consecutive women undergoing percutaneous kidney tumour biopsy for localized kidney cancer in a second high-volume cancer institution. ResultsA total of 113 patients were identified from 2 different institutions. We observed a lower rate of clear cell RCC in the Kidney-breast (KB) group compared to the Kidney-only (KO) group, suggesting a potential association between breast cancer and non-ccRCC. The KB group had a higher proportion of locally advanced tumours and high-grade lesions. Although recurrence-free survival favored the KO cohort, no significant difference was found in cancer-specific survival and overall survival rates between the groups. Noteworthy, patients in the KB group had a higher prevalence of family history of cancer. ConclusionOur findings highlight the need for further research to elucidate the underlying mechanisms and clinical implications of RCC coexisting with breast carcinoma. Understanding the characteristics of this unique population can guide clinical strategies and improve patient outcomes. Level of evidence4.

Single-cell RNA sequencing reveals melanoma cell state-dependent heterogeneity of response to MAPK inhibitors

Melanoma is a heterogeneous cancer influenced by the plasticity of melanoma cells and their dynamic adaptations to microenvironmental cues. Melanoma cells transition between well-defined transcriptional cell states that impact treatment response and resistance. In this study, we applied single-cell RNA sequencing to interrogate the molecular features of immunotherapy-naive and immunotherapy-resistant melanoma tumours in response to exvivo BRAF/MEK inhibitor treatment. We confirm the presence of four distinct melanoma cell states - melanocytic, transitory, neural-crest like and undifferentiated, and identify enrichment of neural crest-like and undifferentiated melanoma cells in immunotherapy-resistant tumours. Furthermore, we introduce an integrated computational approach to identify subsets of responding and nonresponding melanoma cells within the transcriptional cell states. Nonresponding melanoma cells are identified in all transcriptional cell states and are predisposed to BRAF/MEK inhibitor resistance due to pro-inflammatory IL6 and TNFɑ signalling. Our study provides a framework to study treatment response within distinct melanoma cell states and indicate that tumour-intrinsic pro-inflammatory signalling contributes to BRAF/MEK inhibitor resistance. This work was supported by Macquarie University, Melanoma Institute Australia, and the National Health and Medical Research Council of Australia (NHMRC; grant 2012860, 2028055).