Subepithelial immune complex deposition in glomerular disease causes local inflammation and proteinuria by podocyte disruption. A rat model of membranous nephropathy, the passive Heymann nephritis, suggests that Abs against specific podocyte Ags cause subepithelial deposit formation and podocyte foot process disruption. In this study, we present a mouse model in which a polyclonal sheep anti-mouse podocyte Ab caused subepithelial immune complex formation. Mice developed a nephrotic syndrome with severe edema, proteinuria, hypoalbuminemia, and elevated cholesterol and triglycerides. Development of proteinuria was biphasic: an initial protein loss was followed by a second massive increase of protein loss beginning at approximately day 10. By histology, podocytes were swollen. Electron microscopy revealed 60–80% podocyte foot process effacement and subepithelial deposits, but no disruption of the glomerular basement membrane. Nephrin and synaptopodin staining was severely disrupted, and podocyte number was reduced in anti-podocyte serum-treated mice, indicating severe podocyte damage. Immunohistochemistry detected the injected anti-podocyte Ab exclusively along the glomerular filtration barrier. Immunoelectron microscopy localized the Ab to podocyte foot processes and the glomerular basement membrane. Similarly, immunohistochemistry localized mouse IgG to the subepithelial space. The third complement component (C3) was detected in a linear staining pattern along the glomerular basement membrane and in the mesangial hinge region. However, C3-deficient mice were not protected from podocyte damage, indicating a complement-independent mechanism. Twenty proteins were identified as possible Ags to the sheep anti-podocyte serum by mass spectrometry. Together, these data establish a reproducible model of immune-mediated podocyte injury in mice with subepithelial immune complex formation.

ObjectivesSuperficially invasive stage IA squamous vulvar cancer (VSCC) is defined as a single lesion measuring ≤2 cm with a depth of invasion of ≤1.0 mm (FIGO stage IA). This article examines the natural course and prognosis of superficially invasive VSCC.MethodsThis is a retrospective case series of 46 patients (median age 58 years) with superficially invasive stage IA VSCC receiving wide local excision between January 1996 and November 2014 in the University Medical Center Hamburg-Eppendorf.ResultsMedian tumor size was 4 mm. In 39/46 (84.8%) patients peri-tumoral high-grade intraepithelial neoplasia (HSIL) and/or lichen sclerosus (LS) of the vulva were histologically detected: 34 (74.0%) usual type high-grade vulvar intraepithelial neoplasia (uVIN, HSIL), 4 (8.7%) LS with simultaneous VIN (3 uVIN, 1 differentiated VIN (dVIN)), 1 (2.2%) with LS only. 37/46 (80.4%) patients had a R0 resection; in 2 (4.3%) a high-grade VIN was detected in the margin and in 7 (15.2%) the resection status was unknown. The mean follow-up was 58 (range 10–185) months. Four patients (8.7%) suffered from an invasive recurrence after 4, 17, 40, and 54 months, three in the vulva and one in the groin. All local recurrences occurred in women with LS in a combination with high-grade VIN (3 uVIN, 1 dVIN). Two were treated surgically again including inguino-femoral lymphadenectomy (ifLAE) (no regional lymph node metastasis histologically) as invasion depth exceeded 1 mm. The third patient refused treatment. Inguinal recurrence was treated with a bilateral ifLAE, revealing one positive lymph node, followed by adjuvant radiotherapy (groins, pelvis). None of these patients had experienced further recurrences at last follow-up.ConclusionsSuperficially invasive VSCC is characterized by having a very good prognosis. Sole surgical therapy is highly effective. Patients with LS might benefit additionally from intensified surveillance and adequate maintenance therapy in specialized centers.

Therapeutic options in recurrent or metastasized VSCC not amenable to radiotherapy or radical surgery are limited. Evidence for the use of targeted therapies is sparse. All patients with VSCC treated at the Gynecological Cancer Center Hamburg-Eppendorf 2013 - 2019 were retrospectively evaluated for targeted therapeutic approaches. Furthermore, a MEDLINE, EMBASE-, Web of Science-, Scopus- and OVID database search was performed using the terms: ‘vulvar cancer’ AND ‘targeted therapy’, ‘erlotinib’, ‘EGFR’, ‘bevacizumab’, ‘VEGF’, ‘pembrolizumab or ‘immunotherapy’. 12/291 patients (4.1%) with VSCC received at least one targeted therapy at our institution. Previously, one or more platinum-based chemotherapy was applied to all patients (median 3.5 previous lines (range 2-5). In the erlotinib subgroup 2/5 patients (40%) achieved stable disease (SD) while two patients (2/5, 40%) experienced partial response (PR). Treatment was given as monotherapy in 2nd/3rd line for a median of 3.4 months (range 2-6 months). Bevacizumab (n=9) was given as maintenance therapy after platinum-based first-line chemotherapy (9/9), best response was complete response (CR) (n=2/9 22.2%). Median duration of treatment was 7 months (range 4-13 months) with two patients still under ongoing treatment. Best response in the pembrolizumab (n=3) subset was SD (n=1/3 33%). Treatment was given as monotherapy in 2nd/3rd line for a median of 3.3 months (range 3-4 months). 9/12 patients (75%) experienced treatment-related AEs (TRAEs), most commonly grade 1/2. Rapidly evolving antibody treatments have proven clinical benefit especially in HPV-driven tumor entities, however, clinical investigations in VSCC are still limited. These reported cases provide evidence for the clinical utility and feasibility while ensuring an acceptable safety profile.

TN. Rho-kinase inhibition prevents proteinuria in immune-complex-mediated antipodocyte nephritis.