Modified primary tumour/vessel tumour/nodal tumour classification for patients with invasive ductal carcinoma of the breast

Abstract

Background: We previously reported that the primary tumour/vessel tumour/nodal tumour (PVN) classification is significantly superior to the UICC pTNM classification and the Nottingham Prognostic Index for accurately predicting the outcome of patients with invasive ductal carcinoma of the breast in a manner that is independent of the nodal status and the hormone receptor status.

Methods: The purpose of the present study was to compare the outcome predictive power of a modified PVN classification to that of the newly devised pathological UICC pTNM classification and the reclassified Nottingham Prognostic Index in a different group of patients with invasive ductal carcinoma (n=1042) using multivariate analyses by the Cox proportional hazard regression model.

Results: The modified PVN classification clearly exhibited a superior significant power, compared with the other classifications, for the accurate prediction of tumour recurrence and tumour-related death among patients with invasive ductal carcinoma in a manner that was independent of the nodal status, the hormone receptor status, and adjuvant therapy status.

Conclusion: The modified PVN classification is a useful classification system for predicting the outcome of invasive ductal carcinoma of the breast.

Figure 1

Histological factors of the modified PVN classification (A–G). (A) Invasive ductal carcinomas with a fibrotic focus. A fibrotic focus measuring 13.4 × 6.8 mm is visible within the tumour (panoramic view, arrows). The fibrotic focus shows a scar-like feature and is surrounded by invasive ductal carcinoma cells. (B) Invasive ductal carcinoma cells showing marked variations in nuclear features; mitotic figures are also visible in the tumour cells. (C) Several apoptotic bodies and apoptotic tumour cells are visible (arrows), and three mitotic tumour cells (arrowheads) are visible in the tumour embolus in the lymph vessel. (D) One blood vessel tumour embolus is seen adjacent to one artery. Seven apoptotic bodies or apoptotic tumour cells are seen in the blood vessel tumour embolus, and red blood cells are also visible. (E) Lymph node metastases exhibited a severe grade of tumour stroma. (F) Five extranodal blood vessel tumour emboli are seen in metastatic carcinoma to the lymph node (arrows). (G) Six mitotic tumour cells are visible in the tumour of the lymph node (arrows).

Figure 2

Disease-free survival curve and overall survival curve according to the modified PVN classification for all the patients in the present study (A and B). The disease-free survival curve (A) and the overall survival curve (B) for each class significantly decrease according to the increasing order of the classifications (P<0.001).