Association of Tumour Budding With Histological Type And Grade, Pathological Stage And Lymph Node Metastasis In Colorectal Carcinoma

Objective: To investigate the association between the tumour budding of colorectal carcinoma and its histological type, grade, lymph node metastasis, and pathological stage. Study Design: Cross-sectional study Place and Duration of Study: Histopathology Department, Armed Forces Institute of Pathology, Rawalpindi Pakistan, from Dec 2021 to Mar 2023. Methodology: One hundred and twenty colorectal carcinoma patients were examined for existence and severity using Hematoxylin and Eosin-stained sections. According to the number of tumour buds, cases were categorised as low grade (<10/200X), intermediate grade (10-19/200X), and high grade (>20/200X). These categories were related to lymph node involvement, histological type and grade, and pathological staging. In challenging cases, pan-cytokeratin immunohistochemistry labelling was conducted to confirm tumour budding. Results: The mean age of presentation was 55.78±12.47 years. The most common site of involvement was the ascending colon 66(55%), followed by the recto-sigmoid colon 29(24.2%). Most cases were conventional adenocarcinoma 80(67%), followed by mucinous carcinoma 31(26%). Most cases were moderately differentiated 62(52%) and were stage III 79(66%). Forty-two (35%) had low-grade, and thirty-four (28.3%) had intermediate-grade and high-grade tumour budding. Tumour budding significantly correlates with tumour size, histological grade, invasion extent, and lympho-vascular invasion (p-value <0.05). Conclusion: Tumour budding is strongly associated with nodal metastasis and a high grade of colorectal carcinoma; thus, it must be considered an important independent adverse prognostic indicator for colorectal carcinoma.