Sellar germinoma mimicking IgG4-related hypophysitis: a case report

Background The differential diagnosis of IgG4-related hypophysitis and other inflammatory diseases or tumors involving sellar region is challenging even after sellar biopsy. Sellar germinoma is usually infiltrated by lymphocytes or plasma cells, and may be confused with hypophysitis. Case presentation A 36-year-old man with diabetes insipidus, elevated serum IgG4 level (336 mg/dl), and sellar mass was suspected to have IgG4-related hypophysitis, and no other lesion of IgG4-related disease was detected. After treated by prednisone and mycophenolate mofetil, the serum IgG4 decreased to 214 mg/dl. However, after withdrawal of the drugs, the IgG4 level increased to 308 mg/dl. Endocrine assessments revealed panhypopituitarism, and the sellar mass enlarged. Transsphenoidal sellar exploration and biopsy was conducted. Pathological examination showed that the lesion was germinoma with lymphocytes and plasma cells infiltration, and IgG4-staining was positive (70/HPF, IgG4/IgG ratio = 10%). The patient was then treated by cisplatin and etoposide. After four cycles of chemotherapy, the serum IgG4 was 201 mg/dl, and the sellar mass was invisible. Conclusion Sellar germinoma can mimic the clinical characteristics of IgG4-related hypophysitis. Poor response to glucocorticoids can be used as an exclusion criterion in the clinical diagnosis of IgG4-related hypophysitis.

Use of Rituximab as an off-Label medication in Glomerular Diseases: Clinical Perspective

Objectives: We review rituximab (RTX) use and outcomes in immune-mediated glomerular diseases (GN) and compare it to established literature. Methods: Adult GN patients who received RTX between January 2014 and January 2018 in three public hospitals were reviewed. Membranous nephropathy (MN) and minimal change disease (MCD) were considered diseases with literature supporting RTX use. Lupus nephritis (LN), 1o focal segmental glomerulosclerosis (1o FSGS), IgA nephropathy (IgAN), IgG4 related disease, and C3GN had insufficient literature support for RTX use. Clinical Remission was assessed six months after receiving RTX. Results: A total of 61 cases analyzed. RTX was an add on therapy in 87%. Remission rate was 95% in MCD and MN vs. 56 % in off-label group (P=.002). LN patients had a mean initial eGFR of 69mL/min. All class III LN achieved remission, and 11 of 21 class IV achieved remission. Mean initial eGFR for 1o FSGS was 33mL/min and it did not improve, and only 2 of 5 had partial resolution of proteinuria. Proteinuria improved in 3 of 5 IgG4-related disease cases with eGFR stabilization but failed to improve in C3GN cases with eGFR deterioration. Vasculitis cases (6 ANCA-associated vasculitis and 2 IgA vasculitis) were analyzed separately. Remission achieved in only 2 ANCA vasculitis cases, and none in IgA vasculitis cases. Conclusion: Our data support RTX use in resistant MCD and MN. RTX showed success in LN and IgG4 related disease, but not FSGS or C3GN. The small vasculitis cases number does not allow drawing a conclusion on RTX effectiveness.

Ossifying fibrous epulis as an IgG4-related disease of the oral cavity: a case report and literature review

Background Fibrous sclerosing tumours and hypertrophic lesions in IgG4-related disease (IgG4-RD) are formed in various organs throughout the body, but disease in the oral region is not included among individual organ manifestations. We report a case of ossifying fibrous epulis that developed from the gingiva, as an instance of IgG4-RD. Case presentation A 60-year-old Japanese man visited the Department of Oral and Maxillofacial Surgery, Gunma University Hospital, with a chief complaint of swelling of the left mandibular gingiva. A 65 mm × 45 mm pedunculated tumour was observed. The bilateral submandibular lymph nodes were enlarged. The intraoperative pathological diagnosis of the enlarged cervical lymph nodes was inflammation. Based on this diagnosis, surgical excision was limited to the intraoral tumour, which was subsequently pathologically diagnosed as ossifying fibrous epulis. Histopathologically, the ossifying fibrous epulis exhibited increased levels of fibroblasts and collagen fibres, as well as infiltration by numerous plasma cells. The IgG4/IgG cell ratio was > 40%. Serologic analysis revealed hyper-IgG4-emia (> 135 mg/dL). The patient met the comprehensive clinical diagnosis criteria and the American College of Rheumatology and European League Against Rheumatism classification criteria for IgG4-RD. Based on these criteria, we diagnosed the ossifying fibrous epulis in our patient as an IgG4-related disease. A pathological diagnosis of IgG4-related lymphadenopathy was established for the cervical lymph nodes. Concomitant clinical findings were consistent with type II IgG4-related lymphadenopathy. Conclusions A routine serological test may be needed in cases with marked fibrous changes (such as epulis) in the oral cavity and plasma cells, accompanied by tumour formation, to determine the possibility of individual-organ manifestations of IgG4-related disease.

The risk of malignancy in patients with IgG4-related disease: a systematic review and meta-analysis

Background The relationship between IgG4-related disease (IgG4-RD) and the risk of malignancy is still controversial. This article focused on assessing the risk of cancer in patients with IgG4-RD by meta-analysis. Methods We conducted a systematic review of the literature and meta-analysis characterizing the associated risk of overall malignancy and four site-specific malignancies (pancreas, lung, gastric and lymphoma) in patients with IgG4-RD. A search from 2003 to 2020 was performed using specified terms from PubMed, Embase, Web of Science and SinoMed. Random-effects model analysis was used to pool standardized incidence ratios (SIRs) and 95% confidence intervals (CIs). Subgroup and sensitivity analyses were conducted to clarify the heterogeneity of the included studies. Begg’s funnel plot and Egger’s linear regression test were used to evaluate the bias of the meta-analysis. A P value < 0.05 indicated the existence of publication bias. Results A total of 10 studies were included in the article. The overall SIR estimates suggested an increased risk of overall cancer in IgG4-RD patients (SIR 2.57 95% CI 1.72–3.84) compared with the general population. The specific SIRs for pancreas and lymphoma were higher than those of the general population in IgG4-RD patients (SIR 4.07 95% CI 1.04–15.92, SIR 69.17 95% CI 3.91–1223.04, respectively). No significant associations were revealed in respiratory and gastric cancer (SIR 2.14 95% CI 0.97–4.75, SIR 0.95 95% CI 0.24–3.95, respectively). Four studies were found to be the major sources of heterogeneity by sensitivity analysis. There was no evidence of publication bias via Egger’s test. Conclusion Compared with the general population, patients with IgG4-RD appear to have a higher risk of overall cancer, especially pancreatic and lymphoma. The risk of lung and gastric cancer was not different between IgG4-RD patients and the general population.