Diagnostic, Prognostic, and Predictive Role of Ki67 Proliferative Index in Neuroendocrine and Endocrine Neoplasms: Past, Present, and Future

High Ki-67 expression is associated with increased risk of distant recurrence in Oncotype Dx low risk breast cancer

PURPOSE

To assess whether high Ki-67 protein expression level could independently predict the distant recurrence in early-stage breast cancer with low Oncotype Dx scores (≤ 25).

METHODS

This single-center retrospective cohort study included 278 patients with hormone receptor positive (HR+) human epidermal growth factor receptor 2 negative (HER2-), T1-2N0M0, low Oncotype Dx recurrence score (RS) (≤ 25) breast cancer. We identified 2 groups: "high Ki-67″ ≥ 15% (n = 130, 47%) and "low Ki-67″ < 15% (n = 148, 53%). Clinical characteristics, treatment and survival were abstracted from chart review. Fisher's exact test was used to assess differences between Ki-67 groups. Cox-regression models were used to assess differences in survival.

RESULTS

After a median follow up of 7 years, 13 (4.7%) patients experienced distant metastasis. Recurrence rate was significantly higher in the "high Ki-67″ group 9.2% (12/130) versus the "low Ki-67″ group 0.7% (1/148) (P = .001). Distant metastasis-free survival (dMFS) was significantly shorter in the "high Ki-67″ group (HR 12.90, 95% CI, 12.53-13.27, P = .008). Tumor size ≥ 2 cm was associated with shorter dMFS (HR, 12.90; 95% CI, 12.53-13.27; P < .001). In a multivariable analysis, tumor size ≥ 2 cm and "High Ki-67″ were independent prognosis factors for dMFS.

CONCLUSION

Ki-67 expression level may help to identify a subset of low risk Oncotype Dx patients who could benefit from adjuvant chemotherapy.

Nintedanib improves bleomycin-induced pulmonary fibrosis by inhibiting the Clec7a/SPP1 pathway in interstitial macrophages

Idiopathic pulmonary fibrosis (IPF) is a terminal lung disease with high mortality rate. Although Nintedanib (Nin) is an effective treatment for IPF, its precise mechanism of action remains unclear. In this study, we performed an integrated analysis of single-cell sequencing and RNA-seq data from lung tissues of both fibrotic and Nin-treated fibrotic mice to uncover new therapeutic mechanisms of Nin in IPF. Our results revealed an increase in interstitial macrophages following bleomycin (BLM) treatment. We used Monocle2, Cellchat, and in vivo experiments to demonstrate that Nin can inhibit Clec7a in interstitial macrophages, thereby suppressing the SPP1-mediated profibrotic pathway. Additionally, we utilized Scenic to predict transcription factors and identified NFκB as a major transcription factor in interstitial macrophages. In the in vitro experiments, we found that inhibiting Clec7a improved the secretion of SPP1 by M2 macrophages through the NFκB pathway. In subsequent in vivo experiments, we found that inhibiting of Clec7a improves pulmonary fibrosis through the NFκB/SPP1 pathway, and Nin alleviated BLM-induced pulmonary fibrosis by inhibiting Clec7a in interstitial macrophages. In summary, our study indicates that interstitial macrophages are upregulated in pulmonary fibrosis, and Nin reduces fibrosis by inhibiting Clec7a in interstitial macrophages, which in turn diminishes the NFκB /SPP1 pathway. These findings provided a new perspective on the mechanism of action of Nin in treating pulmonary fibrosis.

Utility of the manual hematology cell counter for Ki-67 assessment in gastrointestinal and pancreatobiliary well-differentiated neuroendocrine tumors

In the World Health Organization (WHO) 5th edition, prognosis of gastrointestinal (GI) well-differentiated neuroendocrine tumors (WDNET) depends on proliferation rate, commonly assessed by ki-67 immunohistochemical stain. In daily practice, the gold standard for WHO grade assessment by ki-67 staining, printing a photo of a tumor hotspot, counting the number of ki-67-positive cells out of 500 tumor cells, and calculating a percentage, is time-consuming and many cases are eyeballed. This study investigates the utility of a common tool, the manual cell counter used in hematology smear cell counting, for GI WDNET ki-67 counting. Of 59 resections, the number of cases with a WHO grade difference between gold standard print-and-count and the original report, eyeballing, and hematology counter method, was 23 (39 %), 14 (24 %) and 7 (12 %) cases, respectively. Of 37 biopsies, the number of cases with a WHO grade difference between gold standard print-and-count and the original report, eyeballing, and hematology counter method, was 10 (27 %), 12 (32 %) and 7 (19 %) cases, respectively. For resections, Chi square analysis comparing hematology counter method versus original report, where many cases were likely eyeballed, showed statistically significantly less cases with differing WHO grades from gold standard print-and-count for hematology counter-assessed cases (P = 0.0007), and the same Chi square analysis was marginally not significant (P = 0.09) for hematology counter versus eyeballing. Times taken to perform hematology counter method were statistically significantly lower than times taken for print-and-count. This study suggests the hematology cell counter could strike a reasonable balance between time and accuracy for WDNET resections.

Differences in Clinical, Epidemiological, and Pathological Features of Breast Cancer in the Saudi Population: An Analytical Cross-Sectional Single Institution Study

Background: In Saudi Arabia, breast cancer is the most common malignancy among women, significantly impacting cancer-related morbidity and mortality. The country's unique demographics and rapid socioeconomic development contribute to distinct breast cancer patterns. Objective: To analyze demographic and pathological characteristics of breast cancer with an emphasis on associations between the Ki67 proliferation index, tumor stages, and molecular subtypes. Materials and Methods: An analytical cross-sectional study was conducted on 294 breast cancer patients from 2013 to 2019, recruited from the Comprehensive Cancer Center at King Fahad Medical City, Riyadh, Saudi Arabia. A one-way ANOVA and logistic regression were used to identify risk factors associated with elevated Ki67 levels. Significance was set at a 95% confidence level. Results: The mean age of patients was 51.58. Among them, 67% were overweight/obese, 21.1% were diabetic, and 17% were hypertensive. Approximately 28.9% of all tumors were classified as T3, 46.9% as Grade III, and 40% as Stage IV. Invasive ductal carcinomas (83.9%) were the most common. ER, PR, and HER2 expression were positive in 63.4%, 54.3%, and 34.9% of patients, respectively, with a high Ki67 index in 50.7%. As compared to Grade I cancer, grade II cancer increased the likelihood of elevated Ki67 by 41 times (p = 0.001), Grade III cancer by 7.43 times (p = 0.001), and Stage IV cancer by 2.26 times (p = 0.03). Conversely, invasive lobular carcinomas and other cancer types were significantly less likely to have high Ki67 levels (p < 0.05). Conclusions: Elevated Ki67 appeared to predict higher tumor grades and certain molecular subtypes cancer.

Basic-Clinical Analysis of Parathyroid Cancer

Parathyroid cancer (PC) presents clinically as a case of hyperparathyroidism associated with local compression symptoms. The definitive diagnosis of PC is complex as it requires unequivocal criteria of invasion in postoperative biopsy. Given the difficulty in confirming the diagnosis of PC, attempts have been made to address this problem through the search for biomarkers, mainly using immunohistochemistry. Within this theme, the phenomenon of epithelial-mesenchymal transition and cancer stem cell markers have been scarcely studied; this could eventually help discriminate between a diagnosis of parathyroid adenoma or carcinoma. On the other hand, identification of oncogenes and tumor suppressing genes, as well as epigenetic markers such as miRNAs, lncRNAs, and circRNAs all play a crucial role in tumorigenesis and have enormous potential as diagnostic tools. Furthermore, proteomic-based and inflammatory markers have also been described as diagnostic aids for this uncommon neoplasm. This review presents a clinical approach to the disease, as well as providing a state-of-the-art analysis of basic biomarkers in diagnosis and future projections in this field.

Low Ki-67 labeling index is a clinically useful predictive factor for recurrence-free survival in patients with papillary thyroid carcinoma

BACKGROUND

We report a new risk stratification of invasive stage papillary thyroid carcinomas (PTCs) by combining invasive status, using extrathyroid invasion (Ex) status, and tumor growth speed using the Ki-67 labeling index (LI).

METHODS

We examined tumor recurrence in 167 patients with PTC who were surgically treated at the Kindai University Nara Hospital between 2010 and 2022. The patients were classified according to the degree of invasion [negative (Ex0) or positive (Ex1, Ex2, and Ex3)] and tumor growth speed expressed with Ki-67 LI, as low (<5%) or high (>5%). This study confirmed previous findings that the disease-free survival (DFS) rate in PTCs significantly differed between patients with a high and low Ki-67 index.

RESULTS

When combining Ex status (negative or positive) and Ki-67 proliferation status (low or high), the DFS rate of invasion in the negative, low Ki-67 LI group was only 1.1%, while that of invasion in the positive, high Ki-67 LI was 44.1%. This study reports for the first time that recurrence risks can be stratified accurately when combining carcinoma's essential two features of extrathyroid invasion status and tumor growth speed.

CONCLUSIONS

We believe the evidence for low tumor recurrence risk may contribute to use of more conservative treatment options for invasive-stage PTCs and help alleviate patient anxiety about tumor recurrence and death.

A comprehensive analysis of the prognostic value, expression characteristics and immune correlation of MKI67 in cancers

Background

nuclear-associated antigen Ki67 (Ki67) emerges as a clinically practical biomarker for proliferation assessment among many cancer types. However, the definite prognostic value of Ki67 against a specific cancer type has remained vague. This study aims to perform a comprehensive pan-cancer analysis of the prognosis value of Ki67 across various cancer types.

Methods

This study explored the expression, prognostic value, and tumor-infiltrating immune of MKI67 in the TCGA database by pan-cancer, and then performed immunohistochemical, correlation analysis and prognostic analysis using 10028 patients of the top 10 cancer patients in China we collected. The correlation between MKI67 expression and survival outcome, clinical features, MSI, TMB, and tumor-infiltrating immune cells by TCGA database, xCell, and TIMER algorithms.

Results

MKI67 expression was significantly upregulated across varied cancer types verified by datasets. We found MKI67 expression was significantly associated with poor prognosis in LUADLUSC, LIHC, and BRCA patients, but good prognosis in COADREAD and READ patients via Kaplan-Meier survival analysis using 10028 patients collected. These results of our validation were generally consistent with TCGA database except BRCA, COADREAD and READ. Meanwhile, upregulation of MKI67 elevates the degree of immune infiltration of several immune cell subtypes, such as functional T cells, CD4+ T cells, and CD8+ T cells, as well as, MKI67 was related to Cell cycle, Oocyte meiosis, p53 and other pathways.

Conclusion

Our comprehensive analysis may supply useful guidance on MKI67 applicability across various cancer types. These observed results contribute to the promise of MKI67 in a realistic clinical setting and improve the outcomes of cancer patients.

Oligometastatic Mixed Neuroendocrine Adenocarcinoma of the Esophago-Gastric Junction: A Case of Successful Multidisciplinary Management, the Lessons Learnt and Review of the Literature

Background: Mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs) of the esophago-gastric junction (EGJ) are rare aggressive malignant neoplasms, with, currently, limited evidence regarding the appropriate therapeutic approach. Methods: Herein, we report multimodal treatment management of a patient with oligometastatic MiNEN of EGJ (Siewert III), discuss the lessons learnt, and provide a review of the literature. Results: A 69-year-old female was diagnosed with a locally advanced EGJ tumor and three liver metastases (cT4, cN+, M1). Although the initial histology from biopsy revealed adenocarcinoma, the histopathology of a lymph node biopsy from staging laparoscopy revealed infiltration of neuroendocrine carcinoma cells. Thus, the diagnosis of a mixed neuroendocrine adenocarcinoma was set, and systemic chemotherapy with etoposide and cisplatin was initiated. A major clinical response led to conversion surgical resection of the primary tumor and metastases, followed by adjuvant therapy with immunotherapy. The patient is free of disease at the 3-year follow-up. A review of the literature on similar cases of EGJ or gastric MiNENs revealed a limited number of cases. Out of the 39 patients, 20 of them (51.3%) suffered from advanced-stage disease. The MiNEN diagnosis typically occurred after surgical resection. Systemic chemotherapy against the neuroendocrine component demonstrated significant response rates, while in cases in which conversion surgery was offered, prolongation of survival was demonstrated. Conclusions: Our case and the existing literature on MiNENs of EGJ underline the need for a personalized treatment approach following thorough interpretation of comprehensive pretherapeutic staging. Conversion radical surgery with curative intent could be considered in cases of major or complete clinical response to induction chemotherapy with potentially favorable outcomes.

Clinical and biological heterogeneity of Grade 2 digestive neuroendocrine neoplasms: prognostic significance of the 10% Ki-67 index cutoff and implications for treatment strategies. A longitudinal study

BACKGROUND

Digestive neuroendocrine neoplasms (NENs) encompass a heterogeneous group of tumors with varying prognoses and clinical behaviors. Grade 2 (G2) tumors, defined by a Ki-67 index between 3% and 20%, are particularly challenging to manage due to their intermediate and variable biological behavior. Evidence suggests a distinct prognosis between G2 digestive NENs with a Ki-67 index < 10% and those with a Ki-67 index ≥ 10%.

AIM

To investigate the clinical and biological heterogeneity between Grade 1 (G1) and G2 digestive NENs, and within G2 tumors, with a focus on the prognostic significance of a 10% Ki-67 index cutoff.

METHODS

This study involved a combined retrospective and prospective analysis of patients with low-grade G1 and G2 digestive NENs managed at IRCCS San Gerardo Hospital in Monza, Italy, between January 2000 and May 2024. Data on patient demographics, tumor characteristics, treatment modalities, and survival outcomes were collected and potential differences were analyzed between G1, G2 with Ki-67 index < 10% and G2 with Ki-67 index ≥ 10%.

RESULTS

Out of a total of 113 enrolled patients, 69 (61%) had G1 tumors, and 44 (39%) had G2 tumors. Median tumor size at diagnosis was 19 mm (IQR: 12-25 mm), with primary lesions mainly localized in the pancreas (57% among G1 and 45% among G2). Most G1 tumors were diagnosed at stage I (29 patients, 42%), while the majority of G2 tumors were metastatic at diagnosis (24 patients, 54.5%). Patients with G1 tumors exhibited a slightly higher 5-year OS rate compared to G2 tumors (98.1% vs. 92.8% respectively, though not statistically significant), and a significantly longer median PFS (141 vs. 22 months, p = 0.0003). Within the G2 group, 31 patients (70%) had a Ki-67 index < 10%, while 13 (30%) had a Ki-67 index ≥ 10%, with comparable baseline characteristics. A Ki-67 index < 10% was associated with a significantly better median PFS (38 vs. 8 months for tumors with Ki-67 index ≥ 10% G2 tumors, p = 0.002). PFS after first-line medical therapy was significantly longer in patients with a Ki-67 index < 10%, compared to those with ≥ 10% (undefined vs. 16 months, p = 0.0085), as well as median post-surgical PFS (84 vs. 10.5 months, p < 0.0001). Multivariate analysis identified higher tumor grade, advanced stage at diagnosis, and absence of PRRT as independent predictors of worse outcomes.

CONCLUSIONS

The findings highlight the significant clinical heterogeneity within G2 digestive NENs. A Ki-67 index cutoff of 10% within G2 tumors may serve as a critical prognostic marker, with patients with a Ki-67 index < 10% exhibiting significantly better outcomes in terms of PFS. These results suggest that the Ki-67 index could play an essential role in guiding treatment strategies, emphasizing the need for personalized approaches in managing G2 digestive NENs.

Treating a Non-mixed Neuroendocrine Colorectal Tumor Under Mixed Neuroendocrine Neoplasm (MiNEN) Protocols: A Case Report of Successful Outlier Management

A 65-year-old male presented after a positive Cologuard testing. He was asymptomatic at presentation, with no reported complaints of fever, chills, abdominal pain, diarrhea, constipation, hematochezia, or unexpected weight loss. CT imaging of the abdomen and pelvis revealed a 2 cm mass at the rectosigmoid junction with a single enlarged lymph node nearby measuring 2.7 x 1.6 cm, raising suspicion for regional metastatic adenopathy. He underwent a colonoscopy, which confirmed a rectosigmoid mass. Biopsy results showed adenocarcinoma of the colon. Consequently, the patient was scheduled for a laparoscopic sigmoidectomy with low anterior resection. The pathology of the surgical specimen confirmed adenocarcinoma, moderately differentiated, associated with a component of poorly differentiated large cell neuroendocrine carcinoma, with the neuroendocrine component best developed in the lymph node metastasis. Although the patient did not meet the standard criteria for mixed neuroendocrine-non-neuroendocrine neoplasm (MiNEN) tumors, treatment was administered using chemotherapeutic agents typically reserved for MiNENs. He was treated with platinum-based doublet with good response and has been in remission for one and a half years. This report highlights the importance of flexible therapeutic approaches when pathology marginally deviates from the standard established criteria, illustrating that tailoring treatment to the specific pathology can provide considerable patient benefits.

Small cell lung carcinoma metastatic to the stomach: Commonly overlooked, limited treatment options

Small cell lung carcinoma metastatic to the stomach, whether synchronous or metachronous, is a rare phenomenon accounting for < 0.5% of lung cancers. Hence it can be overlooked by clinicians resulting in delayed diagnosis. This manuscript comments on Yang et al's article which reported 3 such cases. The main diagnostic features are based on routine morphology comprised of small cells with hyperchromatic nuclei, scant cytoplasm, brisk mitoses and necrosis. This can be supplemented by immunohistochemistry demonstrating positivity for cytokeratin, thyroid transcription factor-1 and neuroendocrine markers as well as a high Ki-67 labelling index. Imaging modalities such as positron emission tomography/contrast computed tomography help to confirm lung origin and rule out the possibility of extra-pulmonary small cell carcinoma. The predominant mechanism of spread is most likely hematogeneous. Prognosis is generally poor since this represents stage 4 disease but survival can be improved by chemo/radiotherapy and palliative surgery in select cases. Though outcomes have not changed much in the last several decades, the recent Food and Drug Administration approval of immune checkpoint inhibitors was a significant milestone as was the delineation of small cell lung carcinoma molecular subtypes. Liquid biopsies are increasingly being used for biomarker studies in clinical trials to assess treatment response and prognosis.

Advancements in Molecular Diagnosis and Pharmacotherapeutic Strategies for Invasive Pituitary Adenomas

BACKGROUND

The overwhelming majority of pituitary tumors consist of pituitary adenomas (PAs), which have recently also been termed pituitary neuroendocrine tumors (PitNETs). Clinically significant PAs occur in approximately one in every 1000 individuals, while other types of pituitary tumors, such as craniopharyngiomas and pituicytomas, are significantly less common. Although PAs are generally benign, a subset of them exhibits malignant-like biological traits. They tend to infiltrate and grow aggressively into adjacent tissues and organs, including the dura mater, cavernous sinus, and sphenoid sinus. This invasive behavior often results in the destruction of the normal anatomical architecture of the sella turcica and skull base. Clinically, such tumors are classified as invasive PAs (IPAs), emphasizing their aggressive and destructive nature.

OBJECTIVE AND SIGNIFICANCE

Currently, the diagnostic indicators for IPAs frequently suffer from suboptimal sensitivity and specificity. The invasiveness assessment of PAs lacks a definitive gold standard and instead serves as a predictive tool, with a greater number of indicators met suggesting a higher likelihood of invasiveness. Consequently, a comprehensive approach that integrates imaging, pathological, molecular biological, and other disciplinary metrics is crucial for accurate evaluation. Despite surgery being the primary treatment modality for IPAs, their malignant-like behavior complicates complete resection, resulting in lower resection rates and heightened postoperative recurrence, necessitating multiple surgeries. Therefore, adjunctive drug therapy is often necessary for IPA patients. Preoperative drug therapy can shrink tumor size, facilitating resection and postoperative recovery, mitigating hormone imbalances, delaying recurrence, and enhancing patients' quality of life.

CONCLUSIONS

This article comprehensively reviews the diagnostic criteria for assessing the invasiveness of PAs in the domains of imaging, pathology, and molecular biology, provides an overview of the current research status of drug therapy for these conditions, and deepens our insight into the biological and therapeutic aspects of the tumor microenvironment in PAs.

Consensus Statement: Recommendations on Actionable Biomarker Testing for Thyroid Cancer Management

Thyroid cancer management is rapidly changing. The identification of actionable biomarkers through both germline and somatic testing are now an integral part of directing patient management. However, deficiencies and disparities within existing thyroid cancer biomarker test approaches are resulting in inconsistent application for patient care. An expert panel was convened to create consensus biomarker testing algorithms and recommendations on actionable biomarker testing for patients diagnosed with medullary thyroid cancer, non-anaplastic follicular cell-derived thyroid cancer, or anaplastic follicular cell-derived thyroid cancer who may benefit from targeted therapies. A review of international guidelines was performed to determine the current state, and a literature review was carried out to further evaluate the evidence supporting the use of actionable biomarkers in patients diagnosed with thyroid cancer. Thyroid biomarker-related gaps impacting patient care were also discussed, with an emphasis on the importance of a multidisciplinary team approach for optimal patient care. The recommendations are presented with the aim to help physicians navigate the current thyroid cancer biomarker testing landscape with its many challenges, balancing aspirational care with what is practical and feasible in terms of economic realities and jurisdictional constraints. By remaining therapy-agnostic, these algorithms and recommendations are broadly applicable.

Prognostic value of Ki67 in phyllodes tumor of the breast: A systematic review and meta‑analysis

Numerous clinicopathological features have been examined as predictive factors for adverse outcomes in patients with phyllodes tumor (PT) of the breast, but there are still no definitive predictive markers to guide management, despite the persistent risk of recurrence, even in benign disease. Whether Ki67 has prognostic value in PT remains uncertain. Therefore, a systematic review and meta-analysis were performed to examine whether Ki67 is associated with adverse clinical outcomes, particularly recurrence, in patients with PT. The PubMed/MEDLINE, Web of Science, Scopus, Embase and Cochrane Library databases were searched from inception to July 2024. Study characteristics and outcomes (recurrence and overall survival) according to Ki67 status were extracted from each eligible study, and pooled log odds ratios (OR) with 95% CI were derived using a random-effects model. A total of five studies comprising 280 cases were eligible for inclusion. The adverse outcome rate for the Ki67high (Ki67 >10 or >11.2%) population was 28.7% (95% CI, 20.1-38.6%), while the adverse outcome rate for the Ki67low population was 9.4% (95% CI, 5.4-13.5%). Ki67high was associated with an increased odds of an adverse outcome [log OR, 1.26 (95% CI, 0.38-2.15; P=0.005)] compared with a Ki67low status. All five studies scored 8 points on the Newcastle-Ottawa Scale, equivalent to 'good' quality according to Agency for Healthcare Research and Quality standards, and no significant publication bias was noted. This was the first meta-analysis of the predictive value of Ki67 in PT of the breast. A relatively high Ki67 index (>10%) is associated with recurrence. It is timely to re-evaluate the prognostic value of Ki67 in large retrospective cohorts with long follow-up to firmly establish whether it could contribute to identifying patients at risk of recurrence, particularly those with histologically benign disease. Doing so could impact clinical practice by refining follow-up recommendations based on quality evidence.

Single-cell transcriptomics link gene expression signatures to clinicopathological features of gonadotroph and lactotroph PitNET

BACKGROUND

Pituitary neuroendocrine tumors (PitNET) are among the most common intracranial tumors. Despite a frequent benign course, aggressive behavior can occur. Tumor behavior is known to be under the influence of the tumor microenvironment (TME). However, the relationship between TME cells and aggressive tumor behavior has not been adequately explored in PitNET.

METHODS

We performed differential expression analysis as well as gene expression program identification based on single-cell RNA sequencing to comparatively characterize the transcriptome of seven gonadotroph and three lactotroph PitNET and correlate it with clinical features using bulk RNA-seq data from an independent cohort of 134 PitNET. Tumor immune infiltration was quantified via immunostaining on tissue sections of gonadotroph and lactotroph PitNET.

RESULTS

In lactotroph PitNET, we detect a highly proliferative gene profile with significantly increased expression levels in aggressively growing tumors within bulk RNA-seq data of an independent cohort of 134 PitNET samples. We also report high intratumoral heterogeneity in gonadotroph PitNET (GoPN) and lactotroph PitNET (LaPN) and identify signatures of epithelial, endocrine, and immunological gene networks in both subtypes. A comparison of their TME composition shows enrichment of SPP1+ macrophages and CD4+ T cells in GoPN, as well as enrichment of CD4/CD8 double-negative T cells (DN) and natural killer cells (NK) in LaPN. Also notable is the presence of proliferative lymphocytes, the occurrence of which positively correlates with more aggressive tumor behavior in the bulk RNA-seq cohort. However, increased CD8+ T and NK cell abundances correlate significantly with reduced aggressiveness indicating potential anti-tumoral effects.

CONCLUSIONS

Our study expands the knowledge of the differences in cellular composition of gonadotroph and lactotroph PitNET subtypes. It lays the foundation for further studies on the influence of lymphoid cells on the variable aggressive behavior of PitNET. Regarding the treatment of drug-resistant lactotroph PitNET, proliferative lymphocytes, CD8+ T, and NK cells could represent potentially valuable targets for developing new cancer immunotherapies.

Acidic Pepsin Affects Laryngeal Carcinoma Cell Growth and Invasion Through Glycolysis

OBJECTIVE

The pathogenic mechanism underlying the effects of acidic pepsin in laryngeal cancer remains unclear. This study investigated whether acidic pepsin influences Glut-1 expression and glycolytic activity in laryngeal carcinoma cells and whether it plays a role in the growth and migration of these cells through glycolysis.

STUDY DESIGN

In vitro study.

SETTING

A university-affiliated hospital.

METHODS

Laryngeal carcinoma TU 212 and TU 686 cells were treated with acidic pepsin and 2-deoxy-d-glucose (2-DG), then transfected with Glut-1 small interfering RNA (siRNA). Glucose uptake was detected by a radioimmunoassay counter, lactate secretion was detected by a lactic acid kit, and Glut-1 expression was detected by western blotting. Cell viability, migration and invasion, and clonal formation were assessed using the Cell Counting Kit-8, Transwell chamber, and clonal formation assays, respectively.

RESULTS

Acidic pepsin significantly increased Glut-1 expression in laryngeal carcinoma cells compared with the control group (P < .01). It also significantly enhanced 18F-fluorodeoxyglucose (Cin/Cout) uptake, lactate secretion, cell viability, migration, invasion, and clonal formation in laryngeal carcinoma cells compared with the control group (P < .01). The glycolytic inhibitor 2-DG and Glut-1 siRNA significantly reversed the effects of acidic pepsin on laryngeal carcinoma cells (P < .01).

CONCLUSION

Acidic pepsin enhances the growth and migration of laryngeal carcinoma cells by upregulating Glut-1, thus promoting glycolysis.

Comparative Targeted Genome Profiling between Solid and Liquid Biopsies in Gastroenteropancreatic Neuroendocrine Neoplasms: A Proof-of-Concept Pilot Study

INTRODUCTION

Clinical presentation and genetic profile of gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are highly variable, hampering their management. Sequencing of circulating tumor DNA from liquid biopsy (LB) has been proposed as a less invasive alternative to solid biopsy (SB). Our aim was to compare the mutational profile (MP) provided by LB with that deriving from SB in GEP-NETs.

METHODS

SB and LB were derived simultaneously from 6 GEP-NET patients. A comparative targeted next-generation sequencing (NGS) analysis was performed on DNA from SB and LB to evaluate the mutational status of 11 genes (MEN1, DAXX, ATRX, MUTYH, SETD2, DEPDC5, TSC2, ARID1A, CHECK2, MTOR, and PTEN).

RESULTS

Patients (M:F = 2:1; median age 64 years) included 3 with pancreatic and 3 with ileal NETs. NGS detected a median number of 55 variants/sample in SB and 66.5 variants/sample in LB specimens (mutational burden: 0.2-1.9 and 0.3-1.8 mut/Mb, respectively). Missense and nonsense mutations were prevalent in both, mainly represented by C>T transitions. ARID1A, MTOR, and ATRX were consistently mutated in SB, and ARID1A, TSC2, MEN1, PTEN, SETD2, and MUTYH were consistently mutated in LB. DAXX mutations were absent in LB. Seventeen recurrent mutations were shared between SB and LB; in particular, MTOR single-nucleotide variants c.G4731A and c.C2997T were shared by 5 out of 6 patients. Hierarchical clustering supported genetic similarity between SB and LB.

CONCLUSIONS

This pilot study explores the applicability of LB in GEP-NET MP evaluation. Further studies with larger cohorts are needed to validate LB and to define the clinical impact.

Single-cell sequencing analysis revealed that NEAT1 was a potential biomarker and therapeutic target of prostate cancer

BACKGROUND

Prostate cancer (PCa) usually manifests atypical symptoms in the early stage, and once symptoms appear, most PCa patients have developed to the advanced stage, failing to undergo radical surgery. In this study, PCa occurrence-related biomarkers were explored based on single-cell RNA sequencing (scRNA-seq) data.

METHODS

scRNA-seq data of prostate normal (Normal), benign prostatic hyperplasia (BPH), and PCa (Tumor) samples were acquired from the Gene Expression Omnibus (GEO). Cellular subsets associated with PCa occurrence were obtained using cell annotation. Additionally, the mRNA expression of nuclear enriched abundant transcript 1 (NEAT1) was detected by quantitative real-time PCR (qRT-PCR). The effects of NEAT1 on cell proliferation and apoptosis were analyzed by 5-ethynyl-2-deoxyuridine (EdU) and flow cytometry. Subsequently, cell-derived xenograft (CDX) models were constructed and divided into the LV-NC and LV-shNEAT1 groups. After the tumor tissues of CDX model mice in each group were extracted, the cell growth and Ki67 expression were observed separately using hematoxylin-eosin (H&E) staining and immunohistochemistry (IHC).

RESULTS

Ten cellular subsets were obtained via cell annotation, and significantly differential changes were observed between Basal intermediate and Luminal during the course of BPH to PCa. NEAT1-Luminal was highly recruited in the Tumor group with low stemness and high malignancy scores. Matrix metallopeptidase 7 (MMP7)- keratin 17 (KRT17)-Basal intermediate had high ratios in the Tumor group with low stemness and high malignancy scores. The results of pseudotime analysis revealed that NEAT1-Luminal in the Tumor group were consistently distributed with tumor stage cells. In vitro assays showed that NEAT1 expression was elevated in PCa cells, and NEAT1 knockdown could inhibit cell proliferation and induce apoptosis. CDX assays indicated that silencing NEAT1 could reduce the growth rate of PCa tumor volume in CDX model mice. H&E staining results showed that nuclei of tumor cells were reduced and exhibited lighter color in the LV-shNEAT1 group compared with the LV-NC group. IHC results showed that Ki67 positivity was significantly lower in the LV-shNEAT1 group than in the LV-NC group.

CONCLUSION

NEAT1 expression is increased in PCa, and NEAT1 can be a potential biomarker and therapeutic target for PCa.

Ki-67 as a Marker to Differentiate Burkitt Lymphoma and Diffuse Large B-cell Lymphoma: A Literature Review

Burkitt lymphoma (BL) is a form of non-Hodgkin's lymphoma (NHL) that is characterized by high aggressiveness and arises from the germinal center of B cells. The prevalence of BL in adulthood is less than 5%. However, it encompasses 40% of all childhood NHL. Diffuse large B-cell lymphoma (DLBCL) is the most common lymphoma. It accounts for approximately 25% of all NHL cases worldwide. The differentiation between BL and DLBCL is more clear in theory than in daily practice. However, it is important because it implies different treatments. Compared to the other indolent small cell lymphomas, DLBCLs and BLs show higher Ki-67 index values. The Ki-67 levels in DLBCL typically range from 40% to 90%, while BL has a high Ki-67 positivity, nearing 100%. The aim of this article is to explore and review the function of Ki-67 as a differential marker for BL and DLBCL. An all-language literature search was conducted on MEDLINE, Cochrane, Embase, and Google Scholar until March 2024. The following search strings and Medical Subject Heading (MeSH) terms were used: "Ki-67," "Burkitt lymphoma," and "diffuse large B-cell lymphoma." We comprehensively reviewed the literature on BL, DLBCL, and the Ki-67 marker.

How to standardize the diagnostic approach to pituitary neuroendocrine tumors

Pituitary tumors present heterogeneous biochemical, clinico-radiological, and histological features. Although histologically benign, a non-negligible number of cases present an unpredictable aggressive behavior with local invasiveness, partial/complete resistance to treatment and/or recurrence after surgery, and, rarely, metastasize, overall leading to a significant increase of morbidity, and, thus, requiring skilled multidisciplinary management in referral Centers. Histopathological diagnosis is essential to stratify cancer patient risk and uniform follow-up among Centers. Classification of pituitary neoplasia is continuously evolving in relation to the increased knowledge of mechanisms underlying adenohypophyseal cell tumorigenesis, and the attempts of combining clinico-radiological, biochemical, intraoperative, histological, and molecular elements, with the aim of identifying aggressive forms through. An integrated standardized histopathological report has been proposed in 2019 by the European Pituitary Pathology Group, based on the indications of the 2017 WHO classification of pituitary tumors. The last edition of the WHO Classification of Central Nervous System Tumors and of Endocrine and Neuroendocrine Tumors brought substantial novelties: 1) the replacement of the term "adenoma" with "Pituitary Neuroendocrine Tumor" (PitNET), and of "carcinoma" with "metastatic PitNET," and the consequent ICD-11 recoding from benign to malignant disease; and 2) the pivotal role of lineage restricted pituitary transcription factors for histological typing and subtyping. However, this approach does not reflect the spectrum of tumor phenotypes based on hormone secretion, nor include molecular features. Efforts of interdisciplinary groups of pituitary experts should be strongly encouraged to better understand factors involved in PitNETs evolution and, consequently, standardize diagnosis and reporting based on the most recent knowledges, essential to stratify cancer patient risk and uniform follow-up among centers.

A novel model for predicting postoperative liver metastasis in R0 resected pancreatic neuroendocrine tumors: integrating computational pathology and deep learning-radiomics

BACKGROUND

Postoperative liver metastasis significantly impacts the prognosis of pancreatic neuroendocrine tumor (panNET) patients after R0 resection. Combining computational pathology and deep learning radiomics can enhance the detection of postoperative liver metastasis in panNET patients.

METHODS

Clinical data, pathology slides, and radiographic images were collected from 163 panNET patients post-R0 resection at Fudan University Shanghai Cancer Center (FUSCC) and FUSCC Pathology Consultation Center. Digital image analysis and deep learning identified liver metastasis-related features in Ki67-stained whole slide images (WSIs) and enhanced CT scans to create a nomogram. The model's performance was validated in both internal and external test cohorts.

RESULTS

Multivariate logistic regression identified nerve infiltration as an independent risk factor for liver metastasis (p < 0.05). The Pathomics score, which was based on a hotspot and the heterogeneous distribution of Ki67 staining, showed improved predictive accuracy for liver metastasis (AUC = 0.799). The deep learning-radiomics (DLR) score achieved an AUC of 0.875. The integrated nomogram, which combines clinical, pathological, and imaging features, demonstrated outstanding performance, with an AUC of 0.985 in the training cohort and 0.961 in the validation cohort. High-risk group had a median recurrence-free survival of 28.5 months compared to 34.7 months for the low-risk group, showing significant correlation with prognosis (p < 0.05).

CONCLUSION

A new predictive model that integrates computational pathologic scores and deep learning-radiomics can better predict postoperative liver metastasis in panNET patients, aiding clinicians in developing personalized treatments.

The Prognostic Value of Proliferative Activity in Cutaneous Melanoma: A Pilot Study Evaluating the Mitotic Rate and Ki67 Index to Predict Patient Outcomes

Proliferative activity in cutaneous melanomas can be appreciated both histopathologically by counting mitotic figures and immunohistochemically through the Ki67 index, but the prognostic value of each method is still a matter of debate. In this context, we performed a retrospective study on 33 patients diagnosed with cutaneous melanomas between 2013 and 2018 in order to evaluate progression-free survival and overall survival. Multivariate Cox proportional hazards regression was performed by considering both clinical histopathological and immunohistochemical features. The mitotic rate was significantly independently associated with both outcomes, while the Ki67 index was not an independent prognostic factor. However, the Ki67 predictive accuracy could be improved by establishing both a cut-off value and a standardized protocol for evaluating its expression. Until these desiderata are met, the mitotic rate remains superior to the Ki67 index for predicting prognosis in cutaneous melanomas, as also has the advantage of being easily interpreted in a standard histopathological examination regardless of the pathologist's experience and with no further financial expenses. Importantly, this is one of very few articles that has shown perineural invasion to be an independent prognostic factor for both progression-free survival and overall survival in cutaneous melanomas. As a consequence, this parameter should become a mandatory feature in the histopathological evaluation of cutaneous melanomas as it can improve the identification of patients who are at high risk for disease progression.

A Comprehensive Review and Insights into the New Entity of Differentiated High-Grade Thyroid Carcinoma

Differentiated high-grade thyroid carcinoma (DHGTC) is a new subset within the spectrum of thyroid malignancies. This review aims to provide a comprehensive overview of DHGTC, focusing on its historical perspective, diagnosis, clinical characteristics, molecular profiles, management, and prognosis. DHGTC demonstrates an intermediate prognosis that falls between well-differentiated thyroid carcinoma and anaplastic thyroid carcinoma. Previously unenumerated, this entity is now recognized for its significant impact. Patients with DHGTC often present at an older age with advanced disease and exhibit aggressive clinical behavior. Molecularly, DHGTC shares similarities with other thyroid malignancies, harboring driver mutations such as BRAFV600E and RAS, along with additional late mutations. The unique behavior and histologic features of DHGTC underscore the necessity of precise classification for prognostication and treatment selection. This highlights the critical importance of accurate diagnosis and recognition by pathologists to enrich future research on this entity further.

Molecular Classification of Gastrointestinal and Pancreatic Neuroendocrine Neoplasms: Are We Ready for That?

In the last two decades, the increasing availability of technologies for molecular analyses has allowed an insight in the genomic alterations of neuroendocrine neoplasms (NEN) of the gastrointestinal tract and pancreas. This knowledge has confirmed, supported, and informed the pathological classification of NEN, clarifying the differences between neuroendocrine carcinomas (NEC) and neuroendocrine tumors (NET) and helping to define the G3 NET category. At the same time, the identification genomic alterations, in terms of gene mutation, structural abnormalities, and epigenetic changes differentially involved in the pathogenesis of NEC and NET has identified potential molecular targets for precision therapy. This review critically recapitulates the available molecular features of digestive NEC and NET, highlighting their correlates with pathological aspects and clinical characteristics of these neoplasms and revising their role as predictive biomarkers for targeted therapy. In this context, the feasibility and applicability of a molecular classification of gastrointestinal and pancreatic NEN will be explored.

Recent advances and future challenges in the diagnosis of neuroendocrine neoplasms

Neuroendocrine neoplasms (NEN) are a heterogeneous group of malignancies with increasing incidence, whose diagnosis is usually delayed, negatively impacting on patients' prognosis. The latest advances in pathological classifications, biomarker identification and imaging techniques may provide early detection, leading to personalized treatment strategies. In this narrative review the recent developments in diagnosis of NEN are discussed including progresses in pathological classifications, biomarker and imaging. Furthermore, the challenges that lie ahead are investigated. By discussing the limitations of current approaches and addressing potential roadblocks, we hope to guide future research directions in this field. This article is proposed as a valuable resource for clinicians and researchers involved in the management of NEN. Update of pathological classifications and the availability of standardized templates in pathology and radiology represent a substantially improvement in diagnosis and communication among clinicians. Additional immunohistochemistry markers may now enrich pathological classifications, as well as miRNA profiling. New and multi-analytical circulating biomarkers, as liquid biopsy and NETest, are being proposed for diagnosis but their validation and availability should be improved. Radiological imaging strives for precise, non-invasive and less harmful technique to improve safety and quality of life in NEN patient. Nuclear medicine may benefit of somatostatin receptors' antagonists and membrane receptor analogues. Diagnosis in NEN still represents a challenge due to their complex biology and variable presentation. Further advancements are necessary to obtain early and minimally invasive diagnosis to improve patients' outcomes.

Contemporary Approaches to the Surgical Management of Pancreatic Neuroendocrine Tumors

The incidence of pancreatic neuroendocrine tumors (PNETs) is on the rise primarily due to the increasing use of cross-sectional imaging. Most of these incidentally detected lesions are non-functional PNETs with a small proportion of lesions being hormone-secreting, functional neoplasms. With recent advances in surgical approaches and systemic therapies, the management of PNETs have undergone a paradigm shift towards a more individualized approach. In this manuscript, we review the histologic classification and diagnostic approaches to both functional and non-functional PNETs. Additionally, we detail multidisciplinary approaches and surgical considerations tailored to the tumor's biology, location, and functionality based on recent evidence. We also discuss the complexities of metastatic disease, exploring liver-directed therapies and the evolving landscape of minimally invasive surgical techniques.

Effects of different KRAS mutants and Ki67 expression on diagnosis and prognosis in lung adenocarcinoma

Lung adenocarcinoma (LUAD) is a prevalent form of non-small cell lung cancer with a rising incidence in recent years. Understanding the mutation characteristics of LUAD is crucial for effective treatment and prediction of this disease. Among the various mutations observed in LUAD, KRAS mutations are particularly common. Different subtypes of KRAS mutations can activate the Ras signaling pathway to varying degrees, potentially influencing the pathogenesis and prognosis of LUAD. This study aims to investigate the relationship between different KRAS mutation subtypes and the pathogenesis and prognosis of LUAD. A total of 63 clinical samples of LUAD were collected for this study. The samples were analyzed using targeted gene sequencing panels to obtain sequencing data. To complement the dataset, additional clinical and sequencing data were obtained from TCGA and MSK. The analysis revealed significantly higher Ki67 immunohistochemical scores in patients with missense mutations compared to controls. Moreover, the expression level of KRAS was found to be significantly correlated with Ki67 expression. Enrichment analysis indicated that KRAS missense mutations activated the SWEET_LUNG_CANCER_KRAS_DN and CREIGHTON_ENDOCRINE_THERAPY_RESISTANCE_2 pathways. Additionally, patients with KRAS missense mutations and high Ki67 IHC scores exhibited significantly higher tumor mutational burden levels compared to other groups, which suggests they are more likely to be responsive to ICIs. Based on the data from MSK and TCGA, it was observed that patients with KRAS missense mutations had shorter survival compared to controls, and Ki67 expression level could more accurately predict patient prognosis. In conclusion, when utilizing KRAS mutations as biomarkers for the treatment and prediction of LUAD, it is important to consider the specific KRAS mutant subtypes and Ki67 expression levels. These findings contribute to a better understanding of LUAD and have implications for personalized therapeutic approaches in the management of this disease.

Mixed Neuroendocrine-Non-Neuroendocrine Neoplasms of the Rectum: A Case Report

Introduction

Mixed neuroendocrine-non-neuroendocrine neoplasms (MiNEN) represent roughly 1-2% of all colorectal malignancies. Given the rareness and heterogeneity of these mixed tumors, recognition and accurate diagnosis remain a challenge. In the absence of established guidelines, they are treated according to the standard of care for pure neuroendocrine carcinomas or adenocarcinomas from similar sites of origin.

Case Presentation

We herein report a case of a rectal MiNEN in a 55-year-old male. He underwent colonoscopy for rectal bleeding and mucus emission, which revealed a vegetating lesion located approximately 8 cm from the anal verge, corresponding to a moderately differentiated low-grade adenocarcinoma of the rectum. Computed tomography scan and magnetic resonance imaging uncovered the presence of lung, lymph node, and subcutaneous implant metastases. The biopsy of the cutaneous implant showed neuroendocrine carcinoma Ki-67 90%. The patient underwent systemic chemotherapy.

Conclusion

High-grade MiNEN tumors are the most commonly encountered in clinical practice and have an aggressive biological behavior. Little is known about the genetic drivers of this neoplasm and its pathogenesis remains controversial. Clinical and pathological awareness of this rare entity is a key step to design future targeted therapies and improve treatment options. The aim of this case report is to further our understanding regarding the clinical presentation, radiological features, pathology, management, and prognosis of MiNEN.

Hot Trends in Pheochromocytoma and Paraganglioma: Are We Getting Closer to Personalized Dynamic Prognostication?

Pheochromocytoma and abdominal paraganglioma (PPGL) are rare catecholamine-producing, keratin-negative, non-epithelial neuroendocrine neoplasms characterized by a unique association with syndromic diseases caused by constitutional mutations in a wide range of susceptibility genes. While PPGLs are recognized for their malignant potential, the risk of metastatic disease varies depending on several clinical, histological, and genetic factors. Accurate diagnosis and prognosis of these tumors require a multidisciplinary approach, integrating insights from various medical specialties. Pathologists play a crucial role in this complex task, as numerous morphological, immunohistochemical, and genetic findings can be linked to worse outcomes. Therefore, it is vital to stay informed about the latest advancements in PPGL pathology. This brief review provides an overview of the challenges associated with PPGLs and highlights the most recent developments in tumor prognostication.

Ki67 proliferation index in medullary thyroid carcinoma: a comparative study of multiple counting methods and validation of image analysis and deep learning platforms

AIMS

The International Medullary Thyroid Carcinoma Grading System, introduced in 2022, mandates evaluation of the Ki67 proliferation index to assign a histological grade for medullary thyroid carcinoma. However, manual counting remains a tedious and time-consuming task.

METHODS AND RESULTS

We aimed to evaluate the performance of three other counting techniques for the Ki67 index, eyeballing by a trained experienced investigator, a machine learning-based deep learning algorithm (DeepLIIF) and an image analysis software with internal thresholding compared to the gold standard manual counting in a large cohort of 260 primarily resected medullary thyroid carcinoma. The Ki67 proliferation index generated by all three methods correlate near-perfectly with the manual Ki67 index, with kappa values ranging from 0.884 to 0.979 and interclass correlation coefficients ranging from 0.969 to 0.983. Discrepant Ki67 results were only observed in cases with borderline manual Ki67 readings, ranging from 3 to 7%. Medullary thyroid carcinomas with a high Ki67 index (≥ 5%) determined using any of the four methods were associated with significantly decreased disease-specific survival and distant metastasis-free survival.

CONCLUSIONS

We herein validate a machine learning-based deep-learning platform and an image analysis software with internal thresholding to generate accurate automatic Ki67 proliferation indices in medullary thyroid carcinoma. Manual Ki67 count remains useful when facing a tumour with a borderline Ki67 proliferation index of 3-7%. In daily practice, validation of alternative evaluation methods for the Ki67 index in MTC is required prior to implementation.

The Driver Role of Pathologists in Endocrine Oncology: What Clinicians Seek in Pathology Reports

Endocrine neoplasia represents an increasingly broad spectrum of disorders. Endocrine neoplasms range from incidental findings to potentially lethal malignancies. In this paper, we cover the impact of pathology in the interpretation of the clinic-pathological, genetic, and radiographic features underpinning these neoplasms. We highlight the critical role of multidisciplinary interactions in structuring a rational diagnostic and efficient therapeutic plan and emphasize the role of histopathological input in decision-making. In this context, standardized pathology reporting and second opinion endocrine pathology review represent relevant tools to improve the overall diagnostic workup of patients affected by endocrine tumors in every specific scenario. In fact, although a relevant proportion of cases may be correctly identified based on clinical presentation and biochemical/imaging investigations, a subset of cases presents with atypical findings that may lead to an inappropriate diagnosis and treatment plan based on a wrong pathological diagnosis if all pieces of the puzzle are not correctly considered. Pathologists have a responsibility to actively guide clinicians before and during surgical procedures to prevent unnecessary interventions. In all areas of endocrine pathology, pathologists must understand the complexity of tissue preservation and assay sensitivities and specificities to ensure the optimal quality and interpretation of diagnostic material. Finally, pathologists are central actors in tumor tissue biobanking, which is an expanding field in oncology that should be promoted while adhering to strict ethical and methodological standards.