Anissa Moktefi

Tumor heterogeneity of fibroblast growth factor receptor 3 (FGFR3) mutations in invasive bladder cancer: implications for perioperative anti-FGFR3 treatment

BACKGROUND Fibroblast growth factor receptor 3 (FGFR3) is an actionable target in bladder cancer. Preclinical studies show that anti-FGFR3 treatment slows down tumor growth, suggesting that this tyrosine kinase receptor is a candidate for personalized bladder cancer treatment, particularly in patients with mutated FGFR3. We addressed tumor heterogeneity in a large multicenter, multi-laboratory study, as this may have significant impact on therapeutic response. PATIENTS AND METHODS We evaluated possible FGFR3 heterogeneity by the PCR-SNaPshot method in the superficial and deep compartments of tumors obtained by transurethral resection (TUR, n = 61) and in radical cystectomy (RC, n = 614) specimens and corresponding cancer-positive lymph nodes (LN+, n = 201). RESULTS We found FGFR3 mutations in 13/34 (38%) T1 and 8/27 (30%) ≥T2-TUR samples, with 100% concordance between superficial and deeper parts in T1-TUR samples. Of eight FGFR3 mutant ≥T2-TUR samples, only 4 (50%) displayed the mutation in the deeper part. We found 67/614 (11%) FGFR3 mutations in RC specimens. FGFR3 mutation was associated with pN0 (P < 0.001) at RC. In 10/201 (5%) LN+, an FGFR3 mutation was found, all concordant with the corresponding RC specimen. In the remaining 191 cases, RC and LN+ were both wild type. CONCLUSIONS FGFR3 mutation status seems promising to guide decision-making on adjuvant anti-FGFR3 therapy as it appeared homogeneous in RC and LN+. Based on the results of TUR, the deep part of the tumor needs to be assessed if neoadjuvant anti-FGFR3 treatment is considered. We conclude that studies on the heterogeneity of actionable molecular targets should precede clinical trials with these drugs in the perioperative setting.

Minimal Change Nephrotic Syndrome Associated With Non-hodgkin Lymphoid Disorders: A Retrospective Study of 18 Cases

AbstractFew studies have examined the occurrence of minimal change nephrotic syndrome (MCNS) in patients with non-Hodgkin lymphoma (NHL). We report here a series of 18 patients with MCNS occurring among 13,992 new cases of NHL. We analyzed the clinical and pathologic characteristics of this association, along with the response of patients to treatment, to determine if this association relies on a particular disorder. The most frequent NHLs associated with MCNS were Waldenström macroglobulinemia (33.3%), marginal zone B-cell lymphoma (27.8%), and chronic lymphocytic leukemia (22.2%). Other lymphoproliferative disorders included multiple myeloma, mantle cell lymphoma, and peripheral T-cell lymphoma. In 4 patients MCNS occurred before NHL (mean delay, 15 mo), in 10 patients the disorders occurred simultaneously, and in 4 patients MCNS was diagnosed after NHL (mean delay, 25 mo). Circulating monoclonal immunoglobulins were present in 11 patients. A nontumoral interstitial infiltrate was present in renal biopsy specimens from 3 patients without significant renal impairment. Acute kidney injury resulting from tubular lesions or renal hypoperfusion was present in 6 patients. MCNS relapse occurred more frequently in patients treated exclusively by steroid therapy (77.8%) than in those receiving steroids associated with chemotherapy (25%). In conclusion, MCNS occurs preferentially in NHL originating from B cells and requires an aggressive therapeutic approach to reduce the risk of MCNS relapse.

C1q binding is not an independent risk factor for kidney allograft loss after an acute antibody-mediated rejection episode: a retrospective cohort study

After kidney transplantation, C4d is an incomplete marker of acute antibody‐mediated rejection (AMR) and C1q‐binding donor‐specific antibodies (DSA) have been associated with allograft survival. However, the impact on allograft survival of C1q+ DSA after clinical AMR has not been studied yet. We analysed retrospectively in clinical AMR C4d staining and C1q‐binding impact on allograft survival. We compared clinical, histological and serological features of C4d− and C4d+ AMR, C1q+ and C1q− DSA AMR and analysed C4d and C1q‐binding impact on allograft survival. Among 500 for‐cause kidney allograft biopsies, 48 fulfilled AMR criteria. C4d+ AMR [N = 18 (37.5%)] have significantly higher number class I DSA (P = 0.02), higher microvascular score (P = 0.02) and more transplant glomerulopathy (P = 0.04). C1q+ AMR [N = 20 (44%)] presented with significantly more class I and class II DSA (P = 0.005 and 0.04) and C4d+ staining (P = 0.01). Graft losses were significantly higher in the C4d+ group (P = 0.04) but similar in C1q groups. C4d+ but not C1q+ binding was an independent risk factor for graft loss [HR = 2.65; (1.11–6.34); P = 0.028]. In our cohort of clinical AMR, C4d+ staining but not C1q+ binding is an independent risk factor for graft loss. Allograft loss and patient survival were similar in C1q+ and C1q− AMR.

Membranous Nephropathy Associated With Immunological Disorder-Related Liver Disease: A Retrospective Study of 10 Cases.

Abstract The association between membranous nephropathy (MN) and immunological disorder-related liver disease has not been extensively investigated, and the specific features of this uncommon association, if any, remain to be determined. We retrospectively identified 10 patients with this association. We aimed to describe the clinical, biological, and pathological characteristics of these patients and their therapeutic management. The possible involvement of the phospholipase A2 receptor (PLA2R) in these apparent secondary forms of MN was assessed by immunohistochemistry with renal and liver biopsy specimens. The mean delay between MN and liver disease diagnoses was 3.9 years and the interval between the diagnosis of the glomerular and liver diseases was <1.5 years in 5 patients. MN was associated with a broad spectrum of liver diseases including primary biliary cirrhosis (PBC), autoimmune hepatitis (AIH), and primary sclerosing cholangitis (PSC). AIH whether isolated (n = 3) or associated with PBC (n = 2) or PSC (n = 2) was the most frequent autoimmune liver disease. Circulating PLA2R antibodies were detected in 4 out of 9 patients but the test was performed under specific immunosuppressive treatment in 3 out of 9 patients. Seven of the 9 patients with available renal tissue specimens displayed enhanced expression of PLA2R in glomeruli whereas PLA2R was not expressed in liver parenchyma from these patients or in normal liver tissue. The study of immunoglobulin (Ig) subclasses of deposits in glomeruli revealed that the most frequent pattern was the coexistence of IgG1 and IgG4 immune deposits with IgG4 predominating. Detection of PLA2R antibodies in glomeruli but not in liver parenchyma is a common finding in patients with MN associated with autoimmune liver disease, suggesting that these autoantibodies are not exclusively detected in idiopathic MN.

Reappraisal of HER2 status in the spectrum of advanced urothelial carcinoma: a need of guidelines for treatment eligibility

Although human epidermal growth factor receptor 2 (HER2) may represent a therapeutic target, its evaluation in urothelial carcinoma of the bladder does not rely on a standardized scoring system by immunohistochemistry or fluorescent in situ hybridization (FISH), as reflected by various methodology in the literature and clinical trials. Our aim was to improve and standardize HER2 amplification detection in bladder cancer. We assessed immunohistochemical criteria derived from 2013 American Society of Clinical Oncology (ASCO)/College of American Pathologists (CAPs) guidelines for breast cancer and investigated intratumoral heterogeneity in a retrospective multicentric cohort of 188 patients with locally advanced urothelial carcinoma of the bladder. Immunohistochemistry was performed on 178 primary tumors and 126 lymph node metastases, eligible cases (moderate/strong, complete/incomplete membrane staining) were assessed by FISH. HER2 overexpression was more frequent with 2013 ASCO/CAP than 2007 ASCO/CAP guidelines (p < 0.0001). The rate of positive HER2 FISH was similar between primary tumor and lymph node metastases (8%). Among positive FISH cases, 48% were associated with moderate/strong incomplete membrane staining that were not scored eligible for FISH by 2007 ASCO/CAP criteria. Among 3+ immunohistochemistry score cases, 67% were associated with HER2-positive FISH. Concordance between primary tumors and matched lymph node metastases was moderate for immunohistochemistry (κ = 0.54 (CI 95%, 0.41–0.67)) and FISH (κ = 0.50 (CI 95%, 0.20–0.79)). HER2-positive FISH was more frequent in micropapillary carcinomas (12%) and carcinoma with squamous differentiation (11%) than in pure conventional carcinoma (6%). Intratumoral heterogeneity for HER2 immunohistochemistry was observed in 7% primary tumor and 6% lymph node metastases; 24% positive HER2 FISH presented intratumoral heterogeneity. Our study suggests that HER2 evaluation should include an immunohistochemistry screening step with eligibility for FISH including incomplete/complete and moderate/strong membrane staining. Spatial or temporal intratumoral heterogeneity prompts to perform evaluation on both tumor and lymph node, and for each histological variant observed.

Monotypic plasma cell interstitial nephritis as the only clinical manifestation in a patient with previously undiagnosed indolent multiple myeloma: A case report.

Introduction: Predominantly monotypic plasma cell infiltrates are an uncommon renal finding in patients with malignant lymphoplasmacytic proliferation. Case presentation: We report the case of a 52-year-old man with chronic kidney disease and significant proteinuria associated with a monoclonal immunoglobulin spike (IgG&kgr;). Kidney biopsy revealed the presence of atypical multinucleated CD138+ plasma cells with voluminous nuclei stained exclusively with a &kgr; antibody. Electron microscopy showed mesangial and segmental parietal electron-dense, nonorganized hyaline deposits without immunogold labeling for the &kgr; light chain. The bone marrow aspirate revealed 6% of apparently mature plasmocytes without dystrophy. We therefore concluded that the patient had an indolent multiple myeloma with specific renal involvement in the form of malignant monotypic interstitial plasmacytic infiltration. We initiated a specific chemotherapy regimen including bortezomib–cyclophosphamide–dexamethasone. After 4 months of follow-up, creatinine levels had improved slightly and free &kgr; light-chain levels had decreased significantly within the normal range. Conclusion: This case highlights the need to consider neoplastic interstitial plasma cell infiltration systematically in patients diagnosed with an apparently benign monoclonal gammopathy and to consider adaptation of the chemotherapy regimen, to improve renal function.

Multiple ways to detect IDH2 mutations in angioimmunoblastic T-cell lymphoma: from immunohistochemistry to next-generation sequencing

Angioimmunoblastic T-cell lymphoma (AITL) is a peripheral T-cell lymphoma associated with chemoresistance and a poor prognosis. Various nonsynonymous mutations in the R172 residue of IDH2 are present in 20% to 30% of AITL patients. In addition to their diagnostic value, these mutations are potentially targetable, especially by isocitrate dehydrogenase (IDH) 2 inhibitor, and therefore their identification in a routine setting is clinically relevant. However, in AITL, the neoplastic cells may be scarce, making the identification of molecular anomalies difficult. We evaluated the diagnostic value of different methods to detect IDH2 mutations in formalin-fixed, paraffin-embedded tumor samples. Immunohistochemistry with an anti-IDH2 R172K antibody, Sanger sequencing, high-resolution melting PCR, allele-specific real-time quantitative PCR, and next-generation sequencing (NGS) were applied to biopsy specimens from 42 AITL patients. We demonstrate that the IDH2 R172K antibody is specific to this amino acid substitution and highly sensitive for the detection of the IDH2R172K variant, the most frequent substitution in this disease. In our study, NGS and allele-specific real-time quantitative PCR displayed a good sensitivity, detecting 96% and 92% of IDH2 mutations, respectively, in contrast to Sanger sequencing and high-resolution melting PCR, which showed a significantly lower detection rate (58% and 42%, respectively). These results suggest that a combination of immunohistochemistry and AS-PCR or NGS should be considered for the identification of IDH2 mutations in AITL in a routine setting.

Mott cell interstitial nephritis revealing Waldenström macroglobulinaemia

Dear Editor, A 77-year-old man was referred to our department for a recent deterioration of renal function. Relevant medical history included hypertension, type 2 diabetes, and calreticulinmutated essential thrombocythemia with myelofibrosis. A monoclonal IgM spike, considered to correspond to a monoclonal gammopathy of undetermined significance (MGUS), had been diagnosed 25 years earlier. Physical examination revealed lower limb edema and isolated splenomegaly without enlarged palpable lymph nodes or peripheral neuropathy. Laboratory investigations revealed an impairment of renal function (creatinine = 170 μmol/L versus 115 μmol/L 2 years ago) associated with marked proteinuria (3.2 g/day) and normal albumin concentration. The patient also exhibited anemia (9.8 g/dl) and thrombocytosis (720,000/mm) but electrolyte concentrations were normal. Immunoelectrophoresis analysis demonstrated the presence of a circulating monoclonal IgMκ (4 g/ L). Immunonephelometric assays confirmed the presence of free light-chain kappa at a concentration of 41.7 mg/L with a κ/λ ratio of 1.45. Serum complement levels were within the normal range and no cryoglobulinemia was detected. Urine immunoelectrophoresis was positive for kappa light chain and albuminuria. A renal biopsy demonstrated diabetic glomerulopathy and focal and segmental glomerular sclerosis lesion (not shown), which could be responsible for the marked proteinuria. A striking interstitial infiltration of voluminous, round cells with inconspicuous eccentric nucleus and polychromatophilic cytoplasm on Masson’s trichrome staining was highly suggestive of the presence of Mott cells in the renal parenchyma (Fig. 1(a–b)). They were CD79a-positive, reflecting their lymphoplasmacytic lineage (Fig. 1(c)). Immunofluorescence assays revealed positive staining for the μ chain with κ light chain restriction (Fig.1(d)) in the Mott cells, demonstrating the neoplastic nature of these cells. Ultrastructural analysis showed Russel bodies, corresponding to cytoplasmic immunoglobulins inclusions without crystal formation (Fig.1(e)), and immunogold staining confirmed κ light chain restriction (Fig.1(f)). Computed tomography detected sub-centimeter lymphadenopathy and trephine biopsy of the bone marrow showed lymphoplasmacyt ic lymphoma. As Waldenst röm macroglobulinaemia (WM)-related nephropathy is an established indication for initiation of therapy [1], specific anti-Bruton tyrosine kinase treatment (Ibrutinib) was initiated. * Anissa Moktefi anissa.moktefi@aphp.fr

Acute kidney failure with renal carcinomatous lymphangitis secondary to advanced colon cancer.

A 72-year-old man was admitted with acute kidney failure. His previous medical history included clear-cell renal cell carcinoma of the right kidney treated with an enlarged nephrectomy 1 year ago. An adenocarcinoma of the right colon had been recently diagnosed and treated with a right colectomy and chemotherapy (folinic acid, fluorouracil, and oxaliplatin: cumulative dose 85 mg/m2). Anuria had developed over the previous 3 weeks. Renal ultrasound ruled out obstruction of the left urinary tract, and a Doppler excluded vascular thrombosis. Hemodialysis was started, and a transjugular renal biopsy was performed to determine the cause of kidney injury (Figure 1). Several lymphatic capillaries were dilated by clusters of atypical cells with a high nuclear/cytoplasm ratio, coarse chromatin, and prominent nucleoli. Immunochemistry revealed a nuclear expression of CDX2, a marker for colonic carcinoma (Figure 2). An 18F-fluorodeoxyglucose positron emission tomography/computed tomography examination confirmed the diagnosis of massive, hypermetabolic, carcinomatous lymphangitis in both lungs and kidney. As far as we are aware, this is the first report of a carcinomatous lymphangitis of non-renal origin spreading into the kidney. Whether the carcinomatous lymphangitis per se caused the kidney failure here is uncertain.