A 70-year-old ethnically Chinese female presented via the Emergency Department with a 2-week history of shortness of breath, productive cough, and confusion. A chest radiograph showed focal consolidation, and she was treated with antibiotics for community-acquired pneumonia and delirium. By day seven, her confusion had resolved. As part of the investigative work-up of her confusion, she received a CT head which showed a left frontal extra-axial lesion with patchy calcification (Figure 1). An outpatient MRI brain a month later demonstrated pachymeningeal and leptomeningeal enhancement bifrontally, with more marked changes on the left with underlying vasogenic oedema, and inflammatory opacification of the paranasal sinuses (Figure 2).
She was subsequently admitted to the neurology ward for further assessment. She reported a one year exacerbation in the intensity of her chronic left frontal headache which she has had since her 30 s. They were described as a left frontal ache with migrainous features of nausea and photophobia, with no raised pressure features. She also described a reduced sense of smell and taste for 20 years which transiently improves on receiving prednisolone for exacerbation of asthma. There were no systemic features of arthralgia, weight loss, fevers, rash, or haemoptysis. Past medical history included childhood asthma, allergic contact dermatitis, and hypertension. Medication history included steroid and salbutamol inhalers, enalapril, and paracetamol. She was born in Singapore and has been a resident in the UK for 40 years. Neurological examination was normal with no nuchal rigidity, ophthalmic abnormalities, or cranial nerve signs.
Further investigations revealed a chronically raised ESR (35-63 mm/h) for the past eight years with a normal CRP. She also had a chronically raised serum total IgE (137 kU/L) with a normal eosinophil count. Serum ANA, ANCA, rheumatoid factor, double-stranded DNA, anti-Ro, La, Sm, RNP, Jo1, and Scl-70 were negative. She had a serum IgA kappa paraprotein band of 14 g/L with normal serum-free light-chain ratio, beta2-microglobulin, renal function, calcium, and albumin levels. Serum IgG subclasses including IgG4 were normal. Serum fungal and cerebrospinal fluid (CSF) tuberculosis cultures were negative. Two sets of CSF examination showed normal cell count, protein and glucose levels, negative PCR for herpes simplex, varicella zoster and enteroviruses, and no neoplastic cells. CT chest, abdomen, and pelvis were normal. CT sinus showed chronic rhinosinusitis, and an olfactory cleft biopsy showed inflammatory mucosal changes with no evidence of IgG4-related disease or vasculitis. Bone marrow biopsy showed 10% plasma cells on trephine biopsy and 7% plasma cells on aspirate, and borderline between monoclonal gammopathy of uncertain significance (MGUS) and myeloma. MRI whole body showed diffuse osteopenia but no active myelomatous lesions.
Serial MRI brains over two years showed a slow progression in the left frontal convexity pachymeningeal and leptomeningeal thickening and enhancement and bifrontal gliosis. She underwent an open left frontal meningeal biopsy two years into her initial presentation. Histopathological examination revealed a meningothelial neoplasm with a mitotic count of <4/10 high power fields and a low Ki67 labelling index (Figure 3). It also showed the presence of necrobiotic granulomata associated with elastotic degeneration. This was interpreted as an en-plaque meningioma (the WHO, 2016; Grade I) with associated granulomatous and fibroblastic reaction. Immunohistochemistry showed no tumoural expression of GFAP, CD34, STAT6, SMA, Desmin, MUC4, Cam5.2, or MNF116. Bacterial, fungal, and mycobacterial stains were negative.
It was discussed with the patient that she has a benign slow-growing growth within the meninges which occupies much of her left frontal lobe area and it would be difficult to safely remove the whole plaque. She remains under conservative management with serial radiological and clinical monitoring. If the meningeal areas were to grow more as a globular lump with associated symptoms, targeted resection or other forms of localised treatment may be considered.