The combination of bevacizumab/Avastin and erlotinib/Tarceva is relevant for the treatment of metastatic renal cell carcinoma: the role of a synonymous mutation of the EGFR receptor

Metastatic clear cell renal cell carcinomas (mRCC) over-express the vascular endothelial growth factor (VEGF). Hence, the anti-VEGF antibody bevacizumab/Avastin (BVZ) combined with interferon alpha (IFN) was approved for the treatment of mRCC. However, approval was lost in July 2016 due to the absence of sustained efficacy. We previously showed that BVZ accelerates tumor growth in experimental models of mRCC in mice, results in part explained by down-regulation of the phospho tyrosine phosphatase receptor kappa (PTPRκ) in tumor cells. The epidermal growth factor receptor (EGFR) is a direct target of PTPRκ. Its down-regulation leads to constitutive activation of EGFR, an observation which prompted us to test the effect of the EGFR inhibitor erlotinib/Tarceva (ERLO) in addition to BVZ/IFN. The influence of the long non-coding RNA, EGFR-AS1, on ERLO efficacy was also addressed.

Methods: The effect of BVZ/IFN/ERLO was tested on the growth of experimental tumors in nude mice. The presence of germline mutation in the EGFR was evaluated on cell lines and primary RCC cells. In vitro translation and transfections of expression vectors coding the wild-type or the EGFR mutated gene in HEK-293 cells were used to test the role of EGFR mutation of the ERLO efficacy. Correlation between EGFR/EGFR-AS1 expression and survival was analyzed with an online available data base (TCGA).

Results: Tumor growth was strongly reduced by the triple combination BVZ/IFN/ERLO and linked to reduced levels of pro-angiogenic/pro-inflammatory cytokines of the ELR+CXCL family and to subsequent inhibition of vascularization, a decreased number of lymphatic vessels and polarization of macrophages towards the M1 phenotype. Cells isolated from surgical resection of human tumors presented a range of sensitivity to ERLO depending on the presence of a newly detected mutation in the EGFR and to the presence of EGFR-AS1.

Conclusions: Our results point-out that the BVZ/IFN/ERLO combination deserves testing for the treatment of mRCC that have a specific mutation in the EGFR.

[Peritoneal serous borderline tumor discovered during a cesarean section. A case report]

During a caesarean section performed in a 36-year-old woman, we discovered small granulations on the pelvic peritoneum. Biopsies were performed. The diagnosis of primitive borderline serous tumor was confirmed by pathologists. The patient was operated twice: once for diagnostic evaluation, and again six months later. A radical gesture was then decided for therapeutic purposes. The optimal attitude regarding these borderline peritoneal tumors in young women remains difficult and requires a multidisciplinary workout between pathologists and surgeons.

Gains and complex rearrangements of the 12q13-15 chromosomal region in ordinary lipomas: the "missing link" between lipomas and liposarcomas?

Well-differentiated liposarcomas (WDLPS) classically contain high-level amplification of 12q14-15 sequences, including the MDM2 and CDK4 genes, while lipomas are characterized by simple structural chromosome aberrations often involving HMGA2 at 12q15. Previous studies have shown that low-level gain of the 12q14-15 region, such as trisomy 12 and 12q15-24 duplication, might be sufficient for the development of minimal atypia and formation of WDLPS. Moreover, because some features, such as overexpression of HMGA2, are shared by both lipomas and WDLPS, it has been hypothesized that lipomas and WDLPS may form a genetic and morphological continuum. We report here the results of molecular cytogenetic analysis of 8 lipomas that had unusual chromosomal features resulting in gains of 12q14-15. While 3 cases had simple numerical rearrangements (trisomy 12) or structural rearrangements (unbalanced translocations with 12q gains), 5 cases were particularly intriguing because of peculiar features such as giant chromosomes, supernumerary chromosomes or neocentromeres that usually are the hallmark of WDLPS. Gain of 12q14-15 sequences including extra copies of MDM2 and CDK4 were detected by fluorescence in situ hybridization analysis in all analyzed cases but no expression of MDM2 and CDK4 was observed suggesting that these genomic imbalances had no functional consequence. We observed rearrangements of HMGA2 in 5 out 8 cases. Altogether, our results indicate that moderate gains of 12q are not always associated with a malignant phenotype, and that some intermediary forms exist between classical lipomas and classical WDLPS. Some of these intermediary forms may correspond to a genomic premalignant condition while some may have no malignant potential.

Sources of variability in histological scoring of chronic viral hepatitis

Inter-observer agreement on activity and fibrosis scores used in chronic viral hepatitis has only been studied under selected conditions. The aim of this study was to identify the sources of variability due to specimen characteristics and observers. This study included 254 liver specimens and 15 pathologists and used the Metavir score. In 44 specimens scored by 4 academic pathologists, agreement of Metavir score was good overall, but better for fibrosis (kappa = 0.59) than for activity (kappa = 0.43) and poor for lobular necrosis (kappa = 0.15). The mean agreement was better for senior (0.60 +/- 0.24) than junior pathologists (0.52 +/- 0.30, P < .05). Mean intrabserver agreement was better than inter-observer agreement (0.77 +/- 0.18 vs. 0.58 +/- 0.26, P < .01). In 157 specimens scored by 2 expert pathologists (one senior, one junior), agreement of Metavir score was only good but greatly improved after consensus reading (fibrosis: kappa = 0.48 and 0.77, activity: kappa = 0.44 and 0.70, respectively, before and after consensus). Several causes of disagreement were identified: specimen length, fibrosis class number, observer bias, and putative causes related to Metavir score or specimen. In an intercenter evaluation involving 59 specimens, 1 expert and 10 nonacademic pathologists, agreement was very poor and did not improve over 5 years for activity (kappa = 0.22-0.25) or fibrosis (kappa = 0.13-0.18). In conclusion, the level of experience (specialization, duration, and location of practice) has more influence on agreement than the characteristics of the specimen (length, fibrosis class number, miscellaneous factors). Agreement can be improved by experienced pathologist or consensus reading.

[Primary pleomorphic rhabdomyosarcoma of the kidney in adults: unusual tumor]

Primary rhabdomyosarcoma (RMS) of the kidney in an adult is a very rare and unusual tumor in this site. The clinical signs associated with the flank tumoral syndrome, the histologic appearance of cytoplasmic double striation in rhabdomyoblasts and the immunohistochemical expression of skeletal muscle differentiation (desmin, myoglobin, myogenin) are described in the context of a rapidly evolving renal RMS in a 77-year old man. The differential diagnosis are mainly represented by sarcomatoid renal cell carcinoma. According to the neoplastic extent, the treatment includes radical nephrectomy, chemotherapy and surgery. The prognosis of primary renal RMS is extremely poor, with lymph node, hepatic, bone marrow and pulmonary metastasis and a short survival rate.

Rearrangement involving chromosomes 1 and 8 in a retroperitoneal lipoma

Superficial lipomas are very common benign adipose tissue tumors. In contrast, deep-seated lipomas such as retroperitoneal lipomas, are extremely rare and have to be carefully distinguished from well-differentiated liposarcomas for appropriate treatment and follow-up. We report to, our knowledge, the first cytogenetic analysis of a retroperitoneal lipoma occurring in an adult, which showed a complex rearrangement interpreted as t(1;8)(q32;q22-q23) followed by a pericentric inversion of der(8). There was no detectable rearrangement of chromosome 12, and in particular no 12q14-q15 amplification. Because rearrangements of the 8q11-q13 region involving the PLAG1 gene have been described in lipoblastoma-another kind of benign adipose tumor--we used fluorescence in situ hybridization analysis to determine in the present case the chromosomal breakpoint on 8q was located between the ETO (8q22) and COX6C (8q22-q23) genes at a great distance from PLAG1. Karyotypic analysis of additional cases of retroperitoneal lipomas will be required to assess the significance of chromosome 1 and 8 rearrangements in a continuous effort to attain a better classification of adipose tissue tumors. Of great importance is the determination of such genetic markers as additional tools for the differential diagnosis between benign and malignant forms of adipose tumors, and to avoid erroneous diagnoses.

[Pelvic malignant ectomesenchymoma: a case report]

We report the case of a 19 month old boy referred to our institution because of a pelvic tumor initially identified as an embryonal rhabdomyosarcoma and treated with surgery and chemotherapy. Eight years after the initial surgery, a local tumor recurrence with bone metastasis was found. Histological examination and immunohistochemistry showed a double differentiation with both muscular and neuronal cells. This double differentiation was retrospectively found in the initial tumor, then allowing the diagnosis of malignant ectomesenchymoma also called gangliorhabdomyosarcoma. This rare tumor, occurring mainly during childhood, is composed of neuroblasts and / or ganglion cells and of malignant mesenchymal cells (usually rhabdomyosarcomatous cells).

[Apropos of 1 case of paratesticular papillary serous cystadenocarcinoma]

The occurrence within the testis or paratesticular tissue of serous tumors, similar to ovarian tumors, is rare. This article reports a primary serous paratesticular cystadenocarcinoma in a 39 year-old man. From data of the literature, we offer guidelines for diagnosis, histogenesis and treatment of this rare tumor.

[Prognostic value of Fürhman's grade in renal cell carcinoma. A study of 170 cases]

In order to evaluate the prognostic value of the anatomical stage (pTNM 1992) and of the histological factors (Führman's grade, cellular and architectural types), 170 renal cell carcinoma diagnosed between 1971 and 1991 were reviewed. In univariate analysis, the prognosis was correlated with the anatomical stage and Führman's grade: for the 125 patients without metastasis, grades 1 and 2 had a good prognosis, whereas grades 3 and 4 did poorly. The cellular type was not related to survival. Among architectural types, only the pseudo-sarcomatous type was correlated with prognosis. Multivariate analysis revealed that grade and metastasis at diagnosis were two independent predictors of survival; the grade was prognostically superior to metastasis. Führman's grade is essential in determining prognosis; its statistical value is superior to anatomical stage in multivariate analysis.

[Histopathology of neuroendocrine tumors]

Neuroendocrine (NE) tumors are a heterogeneous group of neoplasms arising in various organs and sharing the features of the NE cell system. The term "neuroendocrine" is used for cells characterized by their secretory products and some cytoplasmic proteins rather than by their localization and embryological derivation. Some tumor types can show a characteristic pattern on conventional histology but, to obtain an accurate diagnosis of many NE tumors it is necessary to employ various special methods, mainly electron microscopy and immuno-histochemistry. The classification of NE tumors in four categories according to Travis et al. is largely used: typical carcinoid and atypical carcinoid are low grade neoplasms; small cell NE carcinoma and large cell NE carcinoma are high grade neoplasms. The size, extension into surrounding tissues, angioinvasion and hormonal function are also important to consider in the prognostic evaluation of some NE tumors. Tumors exhibiting multidirectional differentiation must be classified in carcinoma with interspersed NE cells, carcinoid with interspersed non NE cells, composite tumors and amphricine tumors. Finally, some NE tumors may present features suggesting a Multiple Endocrine Neoplasia, ie. multifocality and association with hyperplasia of endocrine cells.

[Mucinous ductal ectasia. Apropos of 2 cases]

Mucinous ectasia of the pancreas ducts is a recently described cystic lesion which usually occurs in acute pancreatitis. Endoscopic retrograde pancreatography provides diagnosis. Mucinous ductal ectasia is considered to be a precancerous lesion. Surgical exeresis is recommended. Our two cases emphasize the difficulties encountered for differential diagnosis with other cystic lesions of the pancreas.