Tumour budding as a prognostic biomarker in biopsies and resections of neoadjuvant-treated rectal adenocarcinoma.

BACKGROUND: Tumour budding (TB) is a marker of tumour aggressiveness which, when measured in rectal cancer resection specimens, predicts worse outcomes and response to neoadjuvant therapy. We investigated the utility of TB assessment in the setting of neoadjuvant treatment. METHODS AND RESULTS: A single-centre, retrospective cohort study was conducted. TB was assessed using the hot-spot International Tumour Budding Consortium (ITBCC) method and classified by the revised ITBCC criteria. Haematoxylin and eosin (H&E) and AE1/AE3 cytokeratin (CK) stains for ITB (intratumoural budding) in biopsies with PTB (peritumoural budding) and ITB (intratumoural budding) in resection specimens were compared. Logistic regression assessed budding as predictors of lymph node metastasis (LNM). Cox regression and Kaplan-Meier analyses investigated their utility as a predictor of disease-free (DFS) and overall (OS) survival. A total of 146 patients were included; 91 were male (62.3%). Thirty-seven cases (25.3%) had ITB on H&E and 79 (54.1%) had ITB on CK assessment of biopsy tissue. In univariable analysis, H&E ITB [odds (OR) = 2.709, 95% confidence interval (CI) = 1.261-5.822, P = 0.011] and CK ITB (OR = 2.165, 95% CI = 1.076-4.357, P = 0.030) predicted LNM. Biopsy-assessed H&E ITB (OR = 2.749, 95% CI = 1.258-6.528, P = 0.022) was an independent predictor of LNM. In Kaplan-Meier analysis, ITB identified on biopsy was associated with worse OS (H&E, P = 0.003, CK: P = 0.009) and DFS (H&E, P = 0.012; CK, P = 0.045). In resection specimens, CK PTB was associated with worse OS (P = 0.047), and both CK PTB and ITB with worse DFS (PTB, P = 0.014; ITB: P = 0.019). In multivariable analysis H&E ITB predicted OS (HR = 2.930, 95% CI = 1.261-6.809) and DFS (HR = 2.072, 95% CI = 1.031-4.164). CK PTB grading on resection also independently predicted OS (HR = 3.417, 95% CI = 1.45-8.053, P = 0.005). CONCLUSION: Assessment of TB using H&E and CK may be feasible in rectal cancer biopsy and post-neoadjuvant therapy-treated resection specimens and is associated with LNM and worse survival outcomes. Future management strategies for rectal cancer might be tailored to incorporate these findings.

Histopathological tumour microenvironment score independently predicts outcome in primary operable colorectal cancer.

Colorectal cancer (CRC) is a heterogenous malignancy and research is focused on identifying novel ways to subtype patients. In this study, a novel classification system, tumour microenvironment score (TMS), was devised based on Klintrup-Mäkinen grade (KMG), tumour stroma percentage (TSP), and tumour budding. TMS was performed using a haematoxylin and eosin (H&E)-stained section from retrospective CRC discovery and validation cohorts (n = 1,030, n = 787). TMS0 patients had high KMG, TMS1 were low for KMG, TSP, and budding, TMS2 were high for budding, or TSP and TMS3 were high for TSP and budding. Scores were assessed for association with survival and clinicopathological characteristics. Mutational landscaping and Templated Oligo-Sequencing (TempO-Seq) profiling were performed to establish differences in the underlying biology of TMS. TMS was independently prognostic in both cohorts (p < 0.001, p < 0.001), with TMS3 predictive of the shortest survival times. TMS3 was associated with adverse clinical features including sidedness, local and distant recurrence, higher T stage, higher N stage, and presence of margin involvement. Gene set enrichment analysis of TempO-Seq data showed higher expression of genes associated with hallmarks of cancer pathways including epithelial to mesenchymal transition (p < 0.001), IL2 STAT5 signalling (p = 0.007), and angiogenesis (p = 0.017) in TMS3. Additionally, enrichment of immunosuppressive immune signatures was associated with TMS3 classification. In conclusion, TMS represents a novel and clinically relevant method for subtyping CRC patients from a single H&E-stained tumour section.

Predicting rectal cancer tumor budding grading based on MRI and CT with multimodal deep transfer learning: A dual-center study.

Objective: To investigate the effectiveness of a multimodal deep learning model in predicting tumor budding (TB) grading in rectal cancer (RC) patients. Materials and methods: A retrospective analysis was conducted on 355 patients with rectal adenocarcinoma from two different hospitals. Among them, 289 patients from our institution were randomly divided into an internal training cohort (n = 202) and an internal validation cohort (n = 87) in a 7:3 ratio, while an additional 66 patients from another hospital constituted an external validation cohort. Various deep learning models were constructed and compared for their performance using T1CE and CT-enhanced images, and the optimal models were selected for the creation of a multimodal fusion model. Based on single and multiple factor logistic regression, clinical N staging and fecal occult blood were identified as independent risk factors and used to construct the clinical model. A decision-level fusion was employed to integrate these two models to create an ensemble model. The predictive performance of each model was evaluated using the area under the curve (AUC), DeLong's test, calibration curve, and decision curve analysis (DCA). Model visualization Gradient-weighted Class Activation Mapping (Grad-CAM) was performed for model interpretation. Results: The multimodal fusion model demonstrated superior performance compared to single-modal models, with AUC values of 0.869 (95% CI: 0.761-0.976) for the internal validation cohort and 0.848 (95% CI: 0.721-0.975) for the external validation cohort. N-stage and fecal occult blood were identified as clinically independent risk factors through single and multivariable logistic regression analysis. The final ensemble model exhibited the best performance, with AUC values of 0.898 (95% CI: 0.820-0.975) for the internal validation cohort and 0.868 (95% CI: 0.768-0.968) for the external validation cohort. Conclusion: Multimodal deep learning models can effectively and non-invasively provide individualized predictions for TB grading in RC patients, offering valuable guidance for treatment selection and prognosis assessment.

High KRT17 expression in tumour budding indicates immunologically 'hot' tumour budding and predicts good survival in patients with colorectal cancer.

Objectives: Emerging evidence has demonstrated that tumour budding (TB) is negatively associated with T-lymphocyte infiltration in CRC. Despite extensive research, the molecular characteristics of immunologically 'hot' TB remain poorly understood. Methods: We quantified the number of TB by haematoxylin-eosin (H&E) sections and the densities of CD3+ and CD8+ T-lymphocytes by immunohistochemistry in a CRC cohort of 351 cases who underwent curative resection. We analysed the differential expression and T-lymphocyte infiltration score of 37 human epithelial keratins in CRC using RNA sequencing from the TCGA dataset. In 278 TB-positive cases, KRT17 expression was evaluated in tumour centre (TC) and TB with a staining score. Patient demographic, clinicopathological features and survival rates were analysed. Results: In a CRC cohort of 351 cases, low-grade TB was associated with high CD3+ and CD8+ T-cell densities in the invasive margin (IM) but not in the TC. Of 37 human epithelial keratins, only KRT17 expression in TB had an apparent association with TB-grade and T-lymphocyte infiltration. In 278 TB-positive cases, high KRT17 expression in TB (KRT17TB) was negatively associated with low-grade TB and positively associated with high CD3+ and CD8+ T-cell densities in IM. High KRT17TB predicted early tumour grade, absence of lymph node metastasis and absence of tumour deposits. Additionally, patients with high KRT17TB had good overall survival and disease-free survival. Notably, low KRT17TB can specifically identify those patients with a poor prognosis among colorectal cancer patients with low TB and high T-lymphocyte infiltration. Conclusions: KRT17 can be employed as a new indicator for distinguishing different immunological TBs.

A novel grading approach predicts worse outcomes in stage pT1 non-muscle-invasive bladder cancer.

OBJECTIVE: To develop a prognostically relevant scoring system for stage pT1 non-muscle-invasive bladder cancer (NMIBC) incorporating tumour budding, growth pattern and invasion pattern because the World Health Organisation grading system shows limited prognostic value in such patients. PATIENTS AND METHODS: The tissue specimens and clinical data of 113 patients with stage pT1 NMIBC who underwent transurethral resection of bladder tumour were retrospectively investigated. Tumour budding, and growth and invasion patterns were evaluated and categorised into two grade groups (GGs). GGs and other clinical and histopathological variables were investigated regarding recurrence-free survival (RFS), progression-free survival (PFS), cancer-specific survival (CSS) and overall survival (OS) using univariable and multivariable Cox regression analyses. RESULTS: The integration of two tumour budding groups, two growth patterns, and two invasion patterns yielded an unfavourable GG (n = 28; 24.7%) that had a high impact on oncological outcomes. The unfavourable GG was identified as an independent RFS and OS predictor (P = 0.004 and P = 0.046, respectively) and linked to worse PFS (P = 0.001) and CSS (P = 0.001), irrespective of the European Association of Urology risk group. The unfavourable GG was associated with higher rates of BCG-unresponsive tumours (P = 0.006). Study limitations include the retrospective, single-centre design, diverse therapies and small cohort. CONCLUSIONS: We present a morphology-based grading system for stage pT1 NMIBC that correlates with disease aggressiveness and oncological patient outcomes. It therefore identifies a highest risk group of stage pT1 NMIBC patients, who should be followed up more intensively or receive immediate radical cystectomy. The grading incorporates objective variables assessable on haematoxylin and eosin slides and immunohistochemistry, enabling an easy-to-use low-cost approach that is applicable in daily routine. Further studies are needed to validate and confirm these results.

Prognostic significance of tumour budding in noncolorectal gastrointestinal tract and pancreatobiliary tract: a systematic review and meta-analysis.

Tumour budding shows promise as a prognostic factor in various cancers, but its widespread application is hindered by the lack of large, validated studies and standardized criteria. This meta-analysis aims to review and examine the prognostic role of tumour budding specifically in noncolorectal gastrointestinal and pancreatobiliary tract cancers, broadening our perspective on its clinical relevance. The literature review was conducted through PubMed, Embase, and Web of Science from inception till 20 February 2023. Pooled odds ratio (OR) and hazard ratio (HR) with 95% confidence interval (CI) were calculated to assess the relation between tumour budding and clinicopathologic features, as well as overall survival. Each study was evaluated using the Newcastle-Ottawa Scale and both heterogeneity and publication bias were analysed. In this meta-analysis of 57 studies across various cancer types, multivariate HR revealed worse overall survival in oesophageal squamous cell carcinoma (HR 3.34 [95% CI 2.21-5.04]), gastric adenocarcinoma (2.03 [1.38-2.99]), pancreatic ductal adenocarcinoma (2.56 [2.02-3.25]), and biliary tract adenocarcinoma (3.11 [2.46-3.93]) with high-grade tumour budding. Additionally, high-grade tumour budding consistently correlated with adverse clinicopathological features, including lymph node metastasis, lymphovascular invasion, and distant metastasis without any observed inverse association. High heterogeneity was noted. Our study suggests that tumour budding is a valuable prognostic marker in various cancers. Nonetheless, standardized criteria tailored to specific organ types are necessary to enhance its clinical utility.

Role of tumor budding and fibrotic cancer stroma in head and neck squamous cell carcinoma.

BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) is an aggressive cancer with an increased frequency of lymph node metastasis at the time of presentation. Tumour budding, characterised by the presence of a single cell or a small grouping of tumour cells (a cluster containing fewer than five malignant cells) at the invasive front and composition of the fibrotic cancer stroma has been demonstrated to have a growing impact on the behaviour of the solid tumour. However exact role played by them is yet to be defined and a standardized scoring system needs to be incorporated. MATERIAL AND METHODS: A total of 45 histopathologically confirmed cases of HNSCC were included in the study. Hematoxylin and Eosin staining (H&E staining), and immunohistochemistry for CK and alpha-SMA were applied to study the tumour budding and fibrotic cancer stroma in all HNSCC cases. The tumour budding was graded as, Grade 1: 0-4 tumour buds, Grade 2: 5-9 buds and Grade 3: ≥ 10 buds and the nature of fibrotic cancer stroma was categorized as mature, intermediate or immature. RESULTS: Among 45 cases analyzed, well differentiated squamous cell carcinoma (WDSCC; Grade 1) accounted for 42.22% (19 cases), whereas moderately differentiated squamous cell carcinoma (MDSCC; Grade 2) and poorly differentiated squamous cell carcinoma (PDSCC; Grade 3) comprised 48.89% (22 cases) and 8.89% (4 cases) respectively. Tumour budding showed instances of 0-4 buds in 33.3% (Grade 1), 5-9 buds in 48.9% (Grade 2), and ≥ 10 buds in 17.8% of cases. Evaluating tumour stroma, Intermediate stroma led at 51.1%, Mature at 37.8%, and 11.1% displayed Immature stroma. Histologically, < 5 buds were seen in 47.4% of Grade 1 cases, while ≥ 10 buds were in 75.0% of Grade 3 cases, proven statistically significant (p = 0.021). However, an association between T&N Stage and tumour budding lacked significance. WDSCC notably had more mature stroma than MDSCC and PDSCC, whereas MDSCC showed higher rates of intermediate and immature stroma (p < 0.001). Comparatively, no significant correlation existed between fibrotic stroma and tumour budding (p = 0.076). Also, fibrotic stroma was compared with tumour budding, however, no significant correlation was found (p = 0.076) CONCLUSION: This study reveals a significant link between tumour budding, cancer stroma, and WHO tumour grade. Thus, evaluating these factors in HNSCC cases can serve as valuable histological prognostic indicators, aiding in treatment planning and prognosis assessment.

Prognostic significance of tumour budding in Merkel cell carcinoma.

Prognostic factors in Merkel cell carcinoma (MCC) are scarce. Tumour budding (TB) has been shown to have a prognostic role in different cancers but has not been explored in MCC. We aimed to determine if TB influences survival in MCC. We performed a retrospective evaluation of 45 cases of MCC in a cancer centre. This included a survival analysis involving TB in patients with MCC, and we searched for variables associated with TB. The mean age of the patients was 69 years. Histologically, the average Breslow was 11.36 mm, and the mean mitotic rate was 31.9 mitoses/mm2. The diagnosis was made in clinical stages I and II in 40% of cases, 22.2% in stage III, and 37.8% in stage IV. Tumour budding was low ( 10 buds/0.785 mm2) in 24.4%. There were no clinical or pathological features associated with high TB. Among the prognostic factors for 5-year survival, we found that tumour size and clinical stage were statistically associated with survival (p = 0.031 and 0.021), but TB was not. No clinical or pathological characteristics of MCC are associated with any degree of TB. Tumour budding does not influence overall survival.

Tumour budding in cutaneous squamous cell carcinoma: A novel prognosis risk factor.

INTRODUCTION: Most cutaneous squamous cell carcinomas (cSCC) have a good prognosis, there is a small group where metastasis and death occur and the evaluation of this risk is still cause for controversy. Tumour budding is a pattern of histological invasion that is an emerging risk factor in other solid tumours. OBJECTIVE: To examine the association between tumour budding and other known high-risk predictors in cSCC. In addition, the impact of tumour budding on overall survival (OS) and disease-specific survival (DSS) was analysed. METHOD: Retrospective study. It included patients with a diagnosis of non-genital cSCC by excisional biopsy at a university hospital, between 2010 and 2020. A pathologist re-analysed their histological slides and evaluated budding. Univariate and multivariate analyses were made to study the associations. RESULTS: 156 cSCC biopsies were found, and positive tumour budding was found in 13.5%. This correlated with worse DSS and OS. On univariate analysis, budding was correlated with the diameter, thickness of the tumour, histological grade, level of invasion, perineural and lymphovascular invasion, previous radiotherapy, recurrent tumours and lymph node metastasis (LNM). Multivariate analysis: tumour budding was associated with poorly differentiated tumours, prior radiotherapy and LNM. CONCLUSION: An association was found between tumour budding and most known risk factors in cSCC. We found findings that indicate that the presence of tumour budding is associated with a worse prognosis in terms of LNM, OS and DSS. This supports the results of previous work which has suggested that budding could be related to high-risk cSCC.

Can tumour budding change the future of pulmonary adenocarcinoma?

BACKGROUND: Pulmonary adenocarcinoma shows different prognosis even in the same pathological subtype and stage. In this study, it is aimed to investigate the relationship between tumour budding and known prognostic values and clinicopathological features in pulmonary adenocarcinoma. METHODS: In this study, there have been 77 patients diagnosed with primary pulmonary adenocarcinoma. In the evaluation process, the number of budding between 0 and 4 is accepted as low budding (Bd1), the number of budding between 5 and 9 is considered as medium budding (Bd2), and the number of budding above 10 is considered as high budding (Bd3). RESULTS: According to the findings of the study, it can be seen that there is a statistical difference between tumour budding and stromal fibrosis (p < 0.001). The presence of pleural invasion, lymph vascular invasion and perineural invasion in patients with Bd3 is found to be statistically higher than the patients with Bd1 (p = 0.048) (p = 0.041) (p = 0.029). CONCLUSIONS: Tumour budding has been associated with pleural invasion, lymph vascular invasion, perineural invasion, and stromal fibrosis. This study is the first to show the relationship between tumour budding and stromal fibrosis in pulmonary adenocarcinomas. The role of tumour budding in lung cancers remains to be clarified.

Buds, clusters, and transitions in 21st century colorectal carcinoma: revolution or reinvention?†.

Tumour budding (TB) describes single or small groups of neoplastic cells that lack continuity with an advancing tumour front. Poorly differentiated clusters (PDCs) are larger and qualitatively different. TB grade and PDCs may predict a worse outcome in colorectal carcinoma and other cancers and fall into the category of 'invasive front prognostic markers' that also includes intratumoural stroma type. Epithelial-mesenchymal transition (EMT) allows the adoption by epithelial cells of mesenchymal characteristics such as dyscohesion, migration, and stromal invasion. TB and PDCs harbor alterations in EMT-related proteins and RNAs and may be morphological manifestations of EMT. However, persistence of epithelioid features and absence of a full complement of typical alterations in TB and PDCs may indicate 'partial EMT', i.e. an intermediate/hybrid state. Recently, Pavlic et al asserted that TB and PDCs in colorectal cancer represent different manifestations of partial EMT and, perhaps controversially, that TB is closer than PDCs to complete transition. In clinical practice, low inter-observer agreement for invasive front prognostic markers is a potential problem. The UK colorectal cancer pathology dataset advises assessment of TB and recommends the use of an international consensus system, but time will tell if we are adopting reliable prognostic markers or reinventing the wheel. Additional studies of TB, PDCs, and EMT will presumably allow greater insight into their role in tumour development and progression. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Proposal of a grading system for squamous cell carcinoma of the lung - the prognostic importance of tumour budding, single cell invasion, and nuclear diameter.

The prognostic markers of lung squamous cell carcinoma (LSCC) are less investigated. The aim of our study was to evaluate tumour budding (TB), minimal cell nest size, nuclear diameter (ND), and spread through air spaces (STAS) among patients with resected LSCC, semi-quantitatively. Furthermore, we aimed to identify a grading system for the best prognostic stratification of LSCC. Patients who underwent surgical resection at the Department of Surgery, University of Szeged between 2010 and 2016 were included. Follow-up data were collected from medical charts. Morphological characteristics were recorded from histologic revision of slides. Kaplan-Meier analysis, log rank test and Cox proportional-hazards model, ROC curve analysis, and intraclass correlation were utilised. Altogether 220 patients were included. In univariate analysis, higher degree of TB, infiltrative tumour border, larger ND, the presence of single cell invasion (SCI) and STAS were associated with adverse prognosis. Based on our results, we proposed an easily applicable grading scheme focusing on TB, ND, and SCI. In multivariate analysis, the proposed grading system (pOS < 0.001, pRFS < 0.001) and STAS (pOS = 0.008, pRFS < 0.001) were independent prognosticators. Compared to the previously introduced grading systems, ROC curve analysis revealed that the proposed grade had the highest AUC values (AUCOS: 0.83, AUCRFS: 0.78). Each category of the proposed grading system has good (ICC: 0.79-0.88) reproducibility. We validated the prognostic impact of TB, SCI, ND, and STAS in LSCC. We recommend a reproducible grading system combining TB, SCI, and ND for proper prognostic stratification of LSCC patients. Further research is required for validation of this grading scheme.

Microvascular density analysis and histological parameters of oral cancer progression.

OBJECTIVES: This study aimed to investigate the role of blood and lymphatic microvascular density in the progression of oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: The sample was composed of 54 cases of OSCC. The immunoexpression to anti-alpha-smooth muscle actin (α-SMA) and to anti-endoglin (CD105) was used to determine the microvessel density (MVD); anti-podoplanin (D2-40) was used to assess the lymphatic vessel density (LVD); vascular endothelial growth factor (VEGF) was evaluated in malignant cells. The histological differentiation, the worst pattern of invasion (WPOI), tumour thickness and tumour budding (TB) intensity were assessed using haematoxylin-eosin and anti-pan-cytokeratin (AE1/AE3). Patients' age and sex, TNM classification and follow-up time were collected from the medical records. RESULTS: MVD markers presented a similar pattern of expression in blood vessels. However, only α-SMA + MVD was significantly higher among women and in tumours ≤4 cm. LVD was lower in tumours with lymph node metastasis. Regarding the histological parameters, high TB intensity was associated with histological differentiation, advanced clinical stage, greater tumour thickness and reduced disease-free survival. No difference was found in VEGF. CONCLUSIONS: The decrease in OSCC LVD could be related to pathological node involvement, whereas high TB intensity could indicate OSCC progression and worse patient outcomes.

Tumour budding - an additional prognostic factor in colorectal cancer survival.

Tumour budding (TB) in cancer is a phenomenon of tumour cells forming clusters, and it is associated with an epithelial-mesenchymal transition into the extracellular matrix of the tumour. It has been shown that the presence of TB in colorectal cancer (CRC) is associated with worse overall survival, higher possibility for vessel invasion, lymph node involvement, and distant metastases appearance. In this retrospective study TB presence in operated patients for CRC is analysed. In the data from 81 patients, 26 presented with TB. Analysis revealed high statistical significance of the effect of TB presence on the number of metastatic lymph nodes, and the lymphovascular and perineural invasion. A statistically meaningful correlation was found between the presence of TB and CRC survival ( p = 0.016). Patients with right-sided colon cancer presented with worse overall survival ( p = 0.011). The patients who presented lymph node metastases and TB presence had worse overall survival ( p = 0.026 and p = 0.021, respectively). Tumour budding, tumour location, and age over 64 years are found to be the independent prognostic factors in CRC patients. Tumour budding is an important prognostic factor in CRC patients that will contribute to treatment. Pathological examination must consider TB in detail.

Tumour-stroma ratio is a valuable prognostic factor for oral tongue squamous cell carcinoma.

OBJECTIVE: The objectives of this study were to estimate the prognostic value of the tumour-stroma ratio (TSR) and tumour budding (TB) in oral tongue squamous cell carcinoma (OTSCC) and to establish a reliable model to predict the outcome of OTSCC patients. METHODS: A total of 103 patients surgically treated at our hospital were enrolled in this study. Chi-square tests, Kaplan-Meier analyses and Cox proportional hazards regression models were performed for statistical analysis. RESULTS: Fifty-six patients were categorized as stroma-rich, and 47 patients were categorized as stroma-poor. Only pathological grade was associated with the TSR (p = 0.017). Kaplan-Meier analysis showed that stroma-rich, high-intensity budding and high risk groups were associated with worse prognosis. The Cox regression model showed that the TSR was an independent risk factor for OTSCC patients prognosis, and the high risk group was also related to poor prognosis (p < 0.05). TB was significantly associated with poor prognosis but was not an independent risk factor. CONCLUSIONS: We found that patients in the stroma-rich group had a worse long-term prognosis. The TSR is an independent risk factor for OTSCC patients' outcome. In addition, a risk model that combined the TSR and TB proved to be valuable for predicting OTSCC patients' outcome.

Prognostic Significance of Tumour Budding and Desmoplastic Reaction in Intestinal-Type Gastric Adenocarcinoma.

Objective. Tumour budding and desmoplastic reactions in peritumoural stroma are features of the tumour microenvironment that are associated with colorectal cancer prognosis but have not been as thoroughly examined in gastric cancer. We aimed to further characterize the prognostic role of tumour budding and desmoplastic reaction in gastric adenocarcinoma with intestinal differentiation. Methods. 76 curative gastrectomy specimens were identified, excluding post-neoadjuvant cases or cases with >50% diffuse-type histology. Tumour budding was defined and graded according to the International Tumor Budding Consensus Conference recommendations and desmoplastic reaction was classified as described by Ueno et al 2017. Tumour budding and desmoplastic reaction were analyzed for associations with pathologic features and clinical outcomes. Results. Tumour budding was associated with pT (P < .001), pN (P < .004), overall stage (P < .001), LVI (P < .001) and PNI (P = .002). Desmoplastic reaction was associated with pT (P < .001), pN (P = .005), overall stage (P = .031) and PNI (P < .001), but not LVI. Survival analysis showed decreased overall survival (OS) and recurrence-free survival (RFS) for intermediate and high grade tumour budding (P = .031, .014 respectively). Immature stroma was significantly associated with RFS but not OS. Neither tumour budding nor desmoplastic reaction were independent predictors of OS or RFS on multivariate analysis in this cohort. Conclusion. Tumour budding and desmoplastic reaction were associated with known pathologic risk factors. Prognostically, tumour budding was associated with OS and RFS while desmoplastic reaction was associated with RFS only. Our data suggest that tumour budding and desmoplastic reaction have prognostic value in intestinal-type gastric adenocarcinoma.

Prognostic impact of tumour budding in squamous cell carcinoma of the lung: a systematic review and meta-analysis.

Tumour budding is an established prognostic factor in various solid tumours, including colorectal cancers and oral squamous cell carcinomas. However, its role is unclear and needs to be defined for squamous cell carcinoma of the lung (LSCC). Hence, we conducted a systematic review and meta-analysis investigating the prognostic role of tumour budding in LSCC. PubMed, Embase and Scopus were searched for peer-reviewed literature investigating the association between tumour budding and survival outcomes or clinicopathological variables in LSCC. The primary outcomes were pooled estimates for overall and recurrence-free survival with hazard ratio (HR) as the effect measure. The association between tumour budding and clinicopathological parameters was also investigated. Of 243 studies, nine were included, comprising 2546 patients. An increased risk of death [HR = 1.76, 95% confidence interval (CI) = 1.50-2.05, P < 0.00001] and recurrence (HR = 1.37, 95% CI = 1.12-1.68, P = 0.003) was evident in patients with high-grade tumour budding. Sensitivity and subgroup analyses revealed consistent results. Pathological stage II, lymph node metastasis, lymphovascular and pleural invasion were associated with high-grade tumour budding. Tumour budding is a new and promising prognostic factor in patients with LSCC. However, pervasive heterogeneity and publication bias reduces the credibility of these findings and the applicability of tumour budding in clinical practice. Future studies are required to standardise reporting on tumour budding in LSCC.

Significance of tumour budding and invasive characteristics in grading of oral squamous cell carcinoma.

Background: Tumour budding has been recognized as a morphologic marker of tumour invasion. Invasive characteristics such as depth of invasion, mode of invasion and worst pattern of invasion are potentially powerful parameters predicting the regional metastasis. Aim: This study was done to understand the significance of tumour budding and various characteristics of invasion and their impact on grading of oral squamous cell carcinoma. Materials and Methods: An immunohistochemical study was performed on tissue sections obtained from 34 paraffin-embedded blocks of clinically and histologically diagnosed cases of oral squamous cell carcinoma. The sections were stained with pan cytokeratin and observed under high power magnification. Results: Tumour budding and the invasive patterns were found to be significant in OSCC. A proposed grading system based on tumour budding and cell nest was found to have a significant correlation with the WHO grading system. Conclusion: This study demonstrated the importance of using tumour buds as an additional parameter in the grading system and also assessed the importance of invasive patterns, cellular atypia and stromal contents in OSCC.

Cellular dissociation grading on biopsies of pulmonary squamous cell carcinoma provides prognostic information across all stages and is congruent with resection specimen grading.

Grading of squamous cell carcinomas (SCCs) based on tumour budding and cell nest size has been termed cellular dissociation grading (CDG) and was suggested as a robust outcome predictor when assessed in biopsies and resections of various extrapulmonary SCCs. In pulmonary SCC (pSCC), this has so far been shown only for resected cancers. As most lung cancers are inoperable, it is of utmost importance to clarify whether the prognostic impact of CDG is retained in the biopsy setting. Two independent pSCC biopsy cohorts from Munich (n = 134, non-resected) and Heidelberg (n = 135, resected) were assessed. Tumour budding and cell nest size measures were assembled into the three-tiered CDG system (G1-G3). Data were correlated with clinicopathological parameters and overall- (OS), disease-specific- (DSS), and disease-free survival (DFS). Interobserver variability and concordance between biopsy and resection specimen were also investigated. CDG was highly congruent between biopsy and resection specimens (κ = 0.77, p < 0.001). In both pSCC cohorts, biopsy-derived CDG strongly impacted on OS, DSS, and DFS (e.g. DFS: p < 0.001). In multivariate survival analyses, CDG remained a stage independent predictor of survival in both cohorts (DFS: p < 0.001 respectively; hazard ratio Munich cohort: CDG-G2: 4.31, CDG-G3; 5.14; Heidelberg cohort: CDG-G2: 5.87, CDG-G3: 9.07). Interobserver agreement for CDG was almost perfect (κ = 0.84, p < 0.001). We conclude that assessment of CDG based on tumour budding and cell nest size is feasible on pSCC biopsies and harbours stage independent prognostic information in resectable as well as non-resectable pSCC. Integration of this grading approach into clinicopathological routine should be considered.

Tumour budding and poorly differentiated clusters in colon cancer - different manifestations of partial epithelial-mesenchymal transition.

Morphological features including infiltrative growth, tumour budding (TB), and poorly differentiated clusters (PDCs) have a firmly established negative predictive value in colorectal cancer (CRC). Despite extensive research, the mechanisms underlying different tumour growth patterns remain poorly understood. The aim of this study was to investigate the involvement of epithelial-mesenchymal transition (EMT) in TB and PDCs in CRC. Using laser-capture microdissection, we obtained distinct parts of the primary CRC including TB, PDCs, expansive tumour front, and the central part of the tumour, and analysed the expression of EMT-related markers, i.e. the miR-200 family, ZEB1/2, RND3, and CDH1. In TB, the miR-200 family and CDH1 were significantly downregulated, while ZEB2 was significantly upregulated. In PDCs, miR-141, miR-200c, and CDH1 were significantly downregulated. No significant differences were observed in the expression of any EMT-related markers between the expansive tumour front and the central part of the tumour. Our results suggest that both TB and PDCs are related to partial EMT. Discrete differences in morphology and expression of EMT-related markers between TB and PDCs indicate that they represent different manifestations of partial EMT. TB seems to be closer to complete EMT than PDCs. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.