Peritoneal Elastic Lamina Changes and D2-40 Expression in Colorectal Carcinoma: A Histopathological and Immunohistochemical Study EC01-EC05
Dr. Abeer Mohammad Amal,
Villa 6, District C, Suburb 9, 15th May City, Cairo, Egypt.
Introduction: Peritoneal elastic lamina invasion (PELI) has been reported as an important negative prognostic factor in pT3 Colorectal cancer (CRC). Lymphovascular invasion (LVI) is a crucial step in the dissemination of tumour cells and is correlated with lymph node metastasis and adverse prognosis.
Aim: Assess PELI and LVI in colorectal carcinoma cases and determine their role in evaluating pT3 CRC and correlating them with tumour prognostic parameters and pT4a tumours.
Materials and Methods: This retrospective study included 60 cases of CRC including pT3 (40 cases) and pT4a (20 cases). Samples were immunohistochemically analysed for D2-40 to highlight lymphovascular invasion. The pT3 cases stained by Verhoeff’s stain are to detect peritoneal elastic lamina invasion. The presence of PELI and LVI was correlated with clinicopathologic variables.
Results: PELI was associated with lymph node metastasis (p-value=0.001), LVI (p-value=0.009), distant metastasis (p-value=0.036) and advanced TNM stage (p-value <0.001). D2-40 immunostaining identified LVI in 10 cases (16.7%) which could not be identified on H&E. D2-40 detected LVI were significantly correlated with lymph node metastasis (p-value=0.0002), H&E detected LVI (p-value=0.0007), distant metastasis (p-value=0.038) and TNM stage (p-value <0.01). The sensitivity, specificity, positive predictive value, and negative predictive value of lymphovscular invasion identified by D2-40 immunostaining to predict lymph node metastasis were 69.44%, 79.17%, 83.33% and 63.33%, respectively. pT3 cases with positive PELI and D2-40 detected LVI were significantly correlated to adverse prognostic factors.
Conclusion: Positive PELI and D2-40 detected LVI are adverse prognostic factors in patients with pT3 CRC being significant predictors of lymph node deposits, distant metastasis and tumour stage. This would recommend upgrading of pT3 CRC cases with PELI into pT4a that would enable histopathological correlation with patients’ treatment.