Pseudotumours are uncommon complications of haemophilia, occurring in 1%-2% of patients with haemophilia.1 , 2 It is a slowly expanding haematoma as a result of recurrent haemorrhage, surrounded by a fibrous capsule. It can occur in both bone and soft tissue, and progressive enlargement may result in bone destruction and/or muscle and skin necrosis. Pseudotumours by themselves are usually painless though its mass effect can result in nerve compression resulting in pain or neurologic symptoms. It may also predispose to pathologic fractures (as in our case) and superimposed infections.2 , 3.

UNASSIGNED: Sternal pseudotumour is an important but rare entity thought to be an inflammatory, non-neoplastic lesion that can mimic tumours. The purpose of this paper was to illustrate the imaging features of this lesion to avoid unnecessary investigations.
UNASSIGNED: The clinical notes and imaging features of four patients with a diagnosis of sternal pseudotumour were reviewed over a period from February 2016 to July 2019.
UNASSIGNED: All patients were afebrile with no history of trauma. The median age at presentation was 12.5 months. The median length of symptoms prior to presentation was 3.5 days. One patient had a mildly elevated C-reactive protein. Chest radiographs showed a pre-sternal soft-tissue mass, with or without osseous destruction of the subjacent sternum. Ultrasound showed a heterogeneous, hypoechoic pre-sternal soft-tissue mass with variable internal vascularity with extension between sternal ossification centres. CT and MRI showed an enhancing dumbbell-shaped lesion with a pre-sternal and retro-sternal soft-tissue component. The median time to complete resolution was 3 months. One patient had a biopsy that showed chronic inflammation and fibrosis.
UNASSIGNED: These lesions present in young children typically with a 1- to 2-week history of a focal 2- to 4-cm swelling over the sternum. The aetiology is unknown but may be on the basis of a yet-to-be identified pathogen. Inflammatory markers and cultures are normal or mildly elevated. Important differential considerations include sternal osteomyelitis or neoplastic causes such as Ewing sarcoma, rhabdomyosarcoma, Langerhans cell histiocytosis and infantile fibrosarcoma.
UNASSIGNED: Sternal pseudotumor is a rare but important entity to be aware of to avoid unnecessary invasive biopsy or further investigations. Our suggestion is that this is a \'Don\'t touch\' lesion that requires close short-interval follow-up at a surgical outpatient clinic and with ultrasound until resolution.

Inflammatory pseudotumour of the testis is a rare but important clinical entity to be recognised by the surgical trainee. We present a case of a 30-year-old gentleman who presented with a hard painless testicular mass. Ultrasound scrotum revealed a diffuse paratesticular swelling arising from the tunica vaginalis with a normal-appearing testis. Germ cell tumour markers were normal. Exploration through an inguinal approach confirmed it to be arising from the tunica vaginalis. Wide excision of the tumour along with a cuff of adherent tunica albuginea was done. Final histopathology revealed a diffuse fibrous pseudotumour of the tunica vaginalis confirming its benign nature.

UNASSIGNED: Metal reaction and pseudotumor formation are very rare complications following ceramic on polyethylene total hip replacement. Pseudotumors have been described in the case of metal on polyethylene as well as in metal on ceramic interfaces. We report the largest pseudotumor formation to be observed after a thorough literature review following ceramic on polyethylene total hip replacement in a case of ankylosing spondylitis and chronic kidney disease.
UNASSIGNED: The patient had reported 7 years following the index surgery with an uncemented total hip arthroplasty and presented with osteolytic changes of the right proximal femur and later was lost to follow-up due to the COVID-19 pandemic. The patient returned again 2 years later presenting with the pseudotumor. Owing to the presence of extensive osteolysis with gross necrotic muscle mass around the proximal one-third of femur and since bone stock was available, reconstruction of the hip joint was not considered and hence a right side hind-quarter amputation was performed.
UNASSIGNED: This immune reaction was possibly exacerbated due to the underlying ankylosing spondylitis and chronic kidney disease requires more stringent follow up protocols and early intervention. It is, thereby, necessary to evaluate patients with serial radiography following total hip replacement, especially those with conditions which could accelerate the immune responses to the metal. This could potentially avoid an amputation and allow for reconstruction of the hip with appropriate immunomodulation.

BACKGROUND: Granulomatosis with polyangiitis (GPA) is characterised by granulomatous inflammation and small-to-medium vessel necrotising vasculitis, mainly affecting respiratory tract and kidneys. Renal involvement presenting as tumour-like lesions poses diagnostic and treatment challenges.
METHODS: Following the observation of a GPA patient presenting with multiple renal tumour-like lesions, we conducted a systematic literature review on MEDLINE/PubMed, EMBASE, and Cochrane databases. Data gathered from the literature were analysed to summarise the diagnostic approach, management, and outcome of renal GPA-related tumour-like lesions.
RESULTS: a 49-year-old female presented with persistent constitutional symptoms and multiple bilateral renal lesions. Renal biopsy showed chronic interstitial inflammation with necrotising granulomas. Laboratory tests disclosed positive anti-proteinase 3 (PR3) anti-neutrophil cytoplasmic antibody (ANCA) leading to a final diagnosis of GPA. She was effectively treated with high-dose glucocorticoids and rituximab. Literature search yielded 41 articles, concerning 42 GPA patients with renal masses, presenting bilaterally in 23.8% of the cases. Positive PR3-ANCA was observed in 86.5% of the cases. Half of 42 patients showed kidney abnormalities. Treatment with glucocorticoids (83.3%) and immunosuppressive agents (80.9%) resulted in an overall good remission rate and favourable prognosis.
CONCLUSIONS: GPA should be considered in the differential diagnoses of kidney tumour-like lesions. The diagnosis is challenging, and histological examination greatly contributes to the diagnostic work-up.

BACKGROUND: Relapsing or recurrent tumefactive demyelination is rare and has not been studied beyond individual case reports.
OBJECTIVE: We examined the clinical course, neuroimaging, cerebrospinal fluid (CSF), treatment and outcomes of patients with recurrent tumefactive demyelinating lesions (TDLs).
METHODS: We used PubMed to identify reports of recurrent TDLs and included the details of an additional, unpublished patient.
RESULTS: We identified 18 cases (11F, 7 M). The median age at onset of the index TDL was 37 years (range 12-72) and most were solitary lesions 72 % (13/18). CSF-restricted oligoclonal bands (OCBs) were detected in 25 % (4/16). Only one of those tested (n = 13) was positive for AQP4-IgG. A moderate-to-marked treatment response (high dose corticosteroid with or without additional plasmapheresis, IVIg or disease modifying therapies) was evident in 89 % of treated patients. Median EDSS at the median follow-up of 36 months (range 6-144) was 2 (range 1-10). Most remained ambulatory (EDSS < 4 in 13/18), but 1 patient died.
CONCLUSIONS: The median age of patients with relapsing TDLs is similar to that of typical MS, but differences include a lower female:male sex ratio, larger lesions, and a comparative lack of CSF-restricted OCBs. Outcomes vary among this group of patients ranging from minimal disability through to death.

A chronic expanding hematoma (CEH) is a rare clinicopathologic entity that may simulate the clinical and radiologic presentation of soft tissue sarcomas. Etiology has been attributed to repeated exudation and bleeding from capillaries in granulation tissue, resulting in a gradually enlarging mass. A 51-year-old male presented with a large thigh mass following a gunshot wound one year prior. Diagnostic imaging revealed a large complex mass with cystic areas overlying cortical erosions in the femoral diaphysis suggestive of osteomyelitis versus a primary aggressive new growth. Biopsy confirmed CEH and the absence of malignant cells. Hip disarticulation was performed after noting massive necrosis of the thigh compartments and neurovascular compromise. CEH is an important differential diagnosis to be considered in a patient with a slow-growing soft tissue mass and history of significant trauma. Its similar clinical presentation with a soft tissue sarcoma necessitates a high index of suspicion, diagnostic imaging, and biopsy prior to performing definitive surgery.

Plasma cell granuloma is a rare, benign, space occupying lesions occurring after recurrent infections. It most commonly involves young adults with lungs being the most common site. They are usually rounded masses with bony expansion and destruction without any life threatening complications and surgery being the best choice of treatment. Here we reported a 33 year-old female with plasma cell granuloma of the maxillary sinus treated with surgery and no recurrence has been noted.

Paratesticular masses are not infrequent, however the diagnosis is challenging. Differentiation from testicular tumours is of utmost importance. One of the rare forms is a fibrous pseudotumours with only about a couple of hundred cases documented worldwide. We present a case of left paratesticular inflammatory pseudotumour.

Inflammatory myofibroblastic tumour arising from the kidney is a rare occurrence. In this case report, we present a rare case of inflammatory myofibroblastic tumour arising from the kidney diagnosed after the presentation with a large retroperitoneal abscess for the first time in literature. A 55-year-old woman with diabetes mellitus presented to us with painful lump in the left lumbar region of the back for 1-week duration. On examination, there was a firm, diffuse lump in the left lumbar region of the back. Her inflammatory markers were high, but the serum creatinine and blood urea were within the normal range. Abdominal ultrasonography showed a distorted left kidney with a heterogeneous mass consisting cystic and solid components measuring approximately 7 × 9 × 8 cm in size. A contrast-enhanced computed tomography scan showed an 11 × 9 × 9 cm-sized low-density mass posterior to the left kidney with multiple contrast-enhancing septations which appeared posterior to but separate from the left kidney within the left renal fascia. There was breeching of the Gerota\'s fascia with extension posteriorly up to subcutaneous tissue. Since the radiological opinion was in favour of a complex perinephric abscess, open drainage of the abscess was performed after failed attempts of ultrasound-guided drainage. The biopsy of the abscess wall was suggestive of a renal cell carcinoma and radical nephrectomy was planned. Due to tumour invasion, the radical nephrectomy was combined with a splenectomy and the specimen sent for histology. It showed an inflammatory myofibroblastic tumour or pseudotumour with the periphery showing ulceration and abscess formation. The patient had an uneventful recovery following surgery. Thus, we report the first case of renal inflammatory myofibroblastic tumour presenting with a large retroperitoneal abscess extending to the subcutaneous tissue plane. Final diagnosis was made only after radical surgery which was curative.