Comparison between Peritumoral and Intratumoral Budding in Colorectal Cancer

Tumor budding (TB) is classified, based on location, into peritumoral budding (PTB) or intratumoral budding (ITB). This study aimed to evaluate the relationship between PTB and ITB in colorectal cancers (CRCs). PTB and ITB were investigated and subsequently divided into high and low groups. CRCs were divided into three groups: (1) high PTB/ITB, (2) high PTB or ITB, and (3) low PTB/ITB. The clinicopathological and prognostic significances were evaluated according to the three tumor budding (TB) groups. High PTB/ITB and low PTB/ITB were identified in 32 (12.0%) and 135 (50.8%) patients, respectively. A total of 99 patients (37.2%) were found to have high PTB or ITB. TB was significantly correlated with lymphatic and perineural invasion, lymph node metastasis, metastatic lymph node ratio, distant metastasis, and a higher pTNM stage. A significant correlation was found between high PTB and high ITB (p = 0.010). The amount of PTB was found to increase significantly with the amount of ITB (p < 0.001) in a linear regression test. Patients with high PTB/ITB had worse overall and recurrence-free survival than those with high PTB or ITB. Conversely, patients with low PTB/ITB had better overall and recurrence-free survival rates than those with high PTB or ITB. However, there was no significant difference in overall and recurrence-free survival between patients with high PTB/low ITB and high ITB/low PTB (p = 0.336 and p = 0.623, respectively). In summary, the presence of TB, regardless of PTB or ITB, was significantly correlated with aggressive tumor behavior and a worse prognosis than the absence of TB. Additionally, the present study demonstrated that it is feasible to stratify the prognosis of patients based on whether they have both PTB and ITB or only one of the two.

Prognostic Implications of Intratumoral Budding in Colorectal Cancer: Detailed Analysis Based on Tumor-Infiltrating Lymphocytes

BACKGROUND

This study aims to understand the clinical and pathological importance of intratumoral budding (ITB) in colorectal cancer (CRC) and its relationship with tumor-infiltrating lymphocytes (TILs). CRCs can be classified into hot (high immunoscore (IS)) and cold (low IS) tumors.

METHODS

We investigated the number of ITBs in a hotspot area and categorized them into high-ITB (≥5) and low-ITB (<5) groups. The clinicopathological significance of ITB in human CRCs was evaluated, and a detailed analysis based on tumor-infiltrating lymphocytes (TILs) was also performed.

RESULTS

High ITB was identified in 59 of 266 CRC cases (22.2%). High ITB significantly correlated with a poorly differentiated tumor, lympho-vascular invasion, perineural invasion, higher pT stage, lymph node metastasis, and higher metastatic lymph node ratio. High ITB was also significantly correlated with a low IS and low CD8-positive lymphocytic infiltrate. The number of ITBs was substantially higher in the low-IS group than in the high-IS group (3.28 ± 3.31 vs. 2.19 ± 2.59; p = 0.005). High ITB significantly correlated with worse overall survival (p = 0.004). In the low-IS group, CRCs with high ITB had a significantly worse prognosis than those with low ITB (p = 0.021). However, there was no significant difference in prognosis between the high- and low-ITB groups in the high-IS group (p = 0.498).

CONCLUSIONS

Taken together, high ITB was significantly correlated with aggressive tumor behaviors and worse survival in patients with CRCs. In addition, ITB can be useful for the prognostic stratification of CRCs with low IS.

Combined histopathological risk score using TP53 protein expression, CD8+ T cell density and intratumoral budding is an independent predictor of neoadjuvant therapy response in rectal adenocarcinoma

AIMS

Neoadjuvant therapy is the recommended treatment for locally advanced rectal adenocarcinoma; however, there remains significant variability in response to therapy. Tumour protein 53 (TP53) has been associated with therapy response and prognosis with conflicting data. Recently, we demonstrated that immune cell density and intratumoral budding (ITB) are predictive factors in rectal cancer. We investigated the predictive value of TP53 immunohistochemistry with CD8⁺ T cell density and ITB on pretreatment biopsies of rectal adenocarcinoma for response to neoadjuvant therapy.

METHODS AND RESULTS

Pretreatment biopsies of rectal adenocarcinoma from 117 patients with neoadjuvant therapy were analysed for TP53 expression by immunohistochemistry, ITB, CD8⁺ T cell density and mismatch repair protein (MMR) status. Most rectal adenocarcinomas displayed aberrant TP53 expression (86 of 117, 74%). Compared to wild-type TP53, aberrant TP53 expression was associated with proficient MMR status (P = 0.003) and low CD8⁺ T cell density (P = 0.001). Aberrant TP53 was significantly associated with a partial to poor response to neoadjuvant therapy [odds ratio (OR) = 2.42, 95% confidence interval (CI) = 1.04-5.62, P = 0.04]. A combined histopathological risk score (HRS) was created using CD8⁺ T cell density, ITB and TP53 expression. Patients were separated into low (none to one factor) and high (two to three factors) HRS categories. In the multivariable model, patients with a high HRS were 3.25-fold more likely to have a partial or poor response to neoadjuvant therapy (95% CI = 1.48-7.11, P = 0.003).

CONCLUSIONS

Our study demonstrates that aberrant TP53 expression, high ITB and low CD8⁺ T cell density in pretreatment biopsies can help predict response to neoadjuvant therapy. These biomarkers may be helpful in identifying patients at risk for therapy resistance.

Evaluation of Tumor Budding in Primary Colorectal Cancer and Corresponding Liver Metastases Based on H&E and Pancytokeratin Staining

In colorectal cancer, tumor budding is associated with tumor progression and represents an additional prognostic factor in the TNM classification. Tumor buds can be found at the invasive front (peritumoral budding; PTB) and in the tumor center (intratumoral budding; ITB) of primary tumors. Previous studies have shown that tumor buds are also present in colorectal liver metastases (CRLM). Data on the prognostic and predictive role in this clinical context are still sparse and no standardized approach to evaluate budding in CRLM has been published so far. This study aimed to analyze and correlate perimetastatic (PMB) and intrametastatic budding (IMB) on H&E and pancytokeratin staining, compare it to budding results in corresponding primary tumors and to propose a standardized scoring system in CRLM as the basis for future studies. Tumor tissue of 81 primary tumors and 139 corresponding CRLM was used for ngTMA construction. For each primary tumor and metastasis, two punches from the center and two punches from the periphery from areas with highest tumor budding density were included. TMA slides were stained for H&E and pancytokeratin (Pan-CK). PTB, ITB, PMB, and IMB were analyzed and classified as bd1, bd2, and bd3 according to ITBCC guidelines. ITB and PTB as well as IMB and PMB showed significant correlation on H&E and Pan-CK staining. No correlation was found for tumor bud counts in primary tumors and corresponding metastases. The agreement for categorized tumor bud counts showed fair to good agreement for metastases and poor agreement for primary tumors between different classes on H&E and Pan-CK staining. Based on our results, tumor budding in primary tumors and CRLM seems to be different processes which might be the results of differing surrounding microenvironments. The evaluation of tumor budding in CRLM is challenging in cases without desmoplastic stroma reaction or intense perimetastatic ductular reaction. We therefore propose to evaluate tumor budding only in metastases with desmoplastic stroma reaction based on H&E staining since important morphological features are obscured on Pan-CK staining.