Makhlouf Shorouk, Atallah Nehal M, Polotto Susanna, Lee Andrew H S, Green Andrew R, Rakha Emad A
Nottingham Breast Cancer Research Centre, Academic Unit for Translational Medical Sciences, School of Medicine, University of Nottingham, Nottingham NG7 2RD, UK.
Department of Pathology, Faculty of Medicine, Assiut University, Assiut 71515, Egypt.
Cancers (Basel). 2024 May 16;16(10):1893. doi: 10.3390/cancers16101893.
Invasive lobular carcinoma (ILC), the most common special type of breast cancer (BC), has unique clinical behaviour and is different from invasive ductal carcinoma of no special type (IDC-NST). However, ILC further comprises a diverse group of tumours with distinct features. This study aims to examine the clinicopathological and prognostic features of different variants of ILC, with a particular focus on characterising aggressive subtypes.
A large (n = 7140) well-characterised and histologically reviewed BC cohort with treatment and long-term follow-up data was investigated. The cohort was classified based on the WHO classification of tumours into main histological subtypes, including ILC and IDC-NST. ILCs were further classified into variants. Clinicopathological parameters and patient outcomes in terms of BC-specific survival (BCSS) and disease-free survival (DFS) were evaluated.
ILC constituted 11% of the cohort. The most common non-classic ILC variants were pleomorphic (pILC) and solid (sILC), constituting 19% of ILC. Compared to classic and related variants (alveolar, trabecular, papillary, and tubulolobular; cILC), pILC and sILC variants were associated with aggressive tumour characteristics. The histologic grade of ILC was an important prognostic variable. The survival patterns identified an aggressive ILC subtype encompassing pILC and high-grade sILC. These tumours, which comprised 14% of the cases, were associated with clinicopathological characteristics of poor prognosis and had high BC-specific death and recurrence rates compared not only to cILC ( < 0.001) but also to IDC-NST ( = 0.02) patients. Contrasting this, cILC patients had significantly longer BCSS and DFS than IDC-NST patients in the first 10 to 15 years of follow-up. Adjuvant chemotherapy did not improve the outcome of patients with aggressive ILC subtypes.
pILC and high-grade sILC variants comprise an aggressive ILC subtype associated with poor prognostic characteristics and a poor response to chemotherapy. These results warrant confirmation in randomised clinical trials.
浸润性小叶癌（ILC）是乳腺癌（BC）最常见的特殊类型，具有独特的临床行为，与非特殊类型的浸润性导管癌（IDC-NST）不同。然而，ILC进一步包括一组具有不同特征的肿瘤。本研究旨在探讨ILC不同变体的临床病理和预后特征，特别关注侵袭性亚型的特征。
对一个大型（n = 7140）特征明确且经过组织学审查的BC队列进行研究，该队列具有治疗和长期随访数据。根据世界卫生组织肿瘤分类将该队列分为主要组织学亚型，包括ILC和IDC-NST。ILC进一步分为不同变体。评估了临床病理参数以及BC特异性生存（BCSS）和无病生存（DFS）方面的患者结局。
ILC占该队列的11%。最常见的非经典ILC变体是多形性（pILC）和实性（sILC），占ILC的19%。与经典及相关变体（腺泡状、小梁状、乳头状和小管小叶状；cILC）相比，pILC和sILC变体与侵袭性肿瘤特征相关。ILC的组织学分级是一个重要的预后变量。生存模式确定了一种侵袭性ILC亚型，包括pILC和高级别sILC。这些肿瘤占病例的14%，与预后不良的临床病理特征相关，与cILC患者相比（<0.001），不仅BC特异性死亡和复发率高，与IDC-NST患者相比（=0.02）也是如此。与此形成对比的是，在随访的前10至15年中，cILC患者的BCSS和DFS明显长于IDC-NST患者。辅助化疗并未改善侵袭性ILC亚型患者的结局。
pILC和高级别sILC变体构成一种侵袭性ILC亚型，与不良预后特征和化疗反应不佳相关。这些结果有待在随机临床试验中得到证实。
