[Neoadjuvant treatment of breast cancer: implications for the pathologist]. / Place du pathologiste dans la prise en charge néoadjuvante des cancers du sein.

These past few years, neoadjuvant strategy has taken an increasing place in the management of breast cancer patients. This strategy is mainly indicated to obtain a tumour bulk regression allowing a breast conserving surgery in patients that otherwise would have undergone mastectomy. Of note, development of new chemotherapy agents and targeted therapies has critically helped in the progress of neoadjuvant strategy as it is currently associated with better pathological response rates. In this context, the pathologist is at the crossroad of this multidisciplinary process. First, he provides on the initial core needle biopsy the tumour pathological characteristics that are critical for the choice of treatment strategy, i.e. histological type, histological grade, proliferative activity (mitotic count and Ki67/MIB1 index labeling), hormone receptor status (oestrogen receptor and progesterone receptor) and HER2 status. Secondly, the pathologist evaluates the pathological response and the status of surgical margins with regards to the residual tumour on the surgical specimen after neoadjuvant treatment. These parameters are important for the management of the patient, since it has been shown that complete pathological response is associated with improved disease free survival. Several grading systems are used to assess the pathological response in breast and axillary lymph nodes. The most frequently used in France are currently the systems described by Sataloff et al. and Chevallier et al. In this review, we detail the different steps involving the pathologist in neoadjuvant setting, with special regards to the quality process and future perspectives such as emerging predictive biomarkers.

[Adenocarcinomas of nasal cavities and paranasal sinuses: Diagnostic pitfalls in sinonasal glandular lesions]. / Adénocarcinomes des fosses nasales et des sinus : pièges diagnostiques des lésions glandulaires naso-sinusiennes.

Among primitive adenocarcinoma of nasal cavity and paranasal sinus, the 2005 WHO classification distinguishes two main categories: intestinal type adenocarcinoma (ITAC) and low-grade non-intestinal adenocarcinoma, entities with different clinical and epidemiological characteristics. Low-grade adenocarcinoma shows a respiratory type phenotype (CK20-/CK7+/CDX2-/villin-) and ITACs, an intestinal type profile (CK20+/CK7-/CDX2+/villin+). Because of histological, ultrastructural and phenotypical similarities between ITAC and colorectal adenocarcinomas, several studies have discussed a possible common pathway in carcinogenesis. But the review of literature shows conflicting results, suggesting different pathways of pathogenesis. Differential diagnoses of sinonasal intestinal-type adenocarcinoma are mainly respiratory epithelial adenomatoid hamartomas, inverted schneiderian papillomas, salivary glands-type carcinoma and more rarely metastasis of adenocarcinoma.