Expression and quantitative variation of the low-incidence blood group antigen He on some S-s-red cells

BACKGROUND: Red cells devoid of glycophorin B (GPB)-borne S, s, and U antigens are classified as an S-s-U- or S-s-U variant (U+var) and can arise from deletion and nondeletion genetic backgrounds. In nondeletion forms of S-s-U-, little information is available on whether the altered GPB gene (GYPB) is expressed in red cells. STUDY DESIGN AND METHODS: Red cells classified as S-s-U- or S-s-U+var were tested with anti-U, anti-U/GPB, anti-He, and anti-N by hemagglutination. Selected samples were tested by flow cytometry, immunoblotting, and polymerase chain reaction amplification using allele-specific primers. RESULTS: He (MNS6) was found on 23 percent (20/87) of samples. These and another 21 of the 87 samples were agglutinated by an anti-U/GPB reagent; this indicated that approximately 50 percent of S-s-samples possessed GPB variants. The strength of He varied among the samples. Genomic polymerase chain reaction with allele-specific primers showed the presence of expected DNA GPB-like products encoding He. Immunoblotting showed that He was carried on a membrane component with a relative molecular mass indistinguishable from that of GPB. CONCLUSION: The finding of He on S-s- red cells provides direct evidence for the presence of an altered form of GPB in red cells previously thought to be devoid of this glycophorin. Quantitative variation in He antigen expression was observed in a subset of S-s- red cells.     

A custom-made prosthesis attached to an existing femoral component for the treatment of peri- and sub-prosthetic fracture

Peri- and sub-prosthetic fractures, or pathological fractures below an existing well-fixed femoral component, with or without an ipsilateral knee replacement, present a difficult surgical challenge. We describe a simple solution, in which a custom-made prosthesis with a cylindrical design is cemented proximally to the stem of an existing, well-fixed femoral component. This effectively treats the fracture without sacrificing the good hip. We describe five patients with a mean age of 73 years (60 to 81) and a mean follow-up of 47 months (6 to 108). The mean overlap of the prosthesis over the femoral component was 7.5 cm (5.5 to 10). There have been no mechanical failures, no new infections and no re-operations. We suggest that in highly selected cases, in which conventional fixation is not feasible, this technique offers a durable option and avoids the morbidity of a total femoral replacement.     

Biological reconstruction after excision, irradiation and reimplantation of diaphyseal tibial tumours using an ipsilateral vascularised fibular graft

The purpose of this study was to assess the outcome of 15 patients (mean age 13.6 years (7?to 25)) with a primary sarcoma of the tibial diaphysis who had undergone excision of the affected segment that was then irradiated (90?Gy) and reimplanted with an ipsilateral vascularised fibular graft within it. The mean follow-up was 57 months (22 to 99). The mean time to full weight-bearing was 23 weeks (9 to 57) and to complete radiological union 42.1 weeks (33 to 55). Of the 15?patients, seven required a further operation, four to obtain skin cover. The mean Musculoskeletal Society Tumor Society functional score at final follow-up was 27 out of 30 once union was complete. The functional results were comparable with those of allograft reconstruction and had a similar rate of complication. We believe this to be a satisfactory method of biological reconstruction of the tibial diaphysis in selected patients.     

Early results of a non-invasive extendible prosthesis for limb-salvage surgery in children with bone tumours

We reviewed our initial seven-year experience with a non-invasive extendible prosthesis in 34 children with primary bone tumours. The distal femur was replaced in 25 cases, total femur in five, proximal femur in one and proximal tibia in three. The mean follow-up was 44?months (15 to 86) and 27 patients (79%) remain alive. The prostheses were lengthened by an electromagnetic induction mechanism in an outpatient setting and a mean extension of 32 mm (4 to 80) was achieved without anaesthesia. There were lengthening complications in two children: failed lengthening in one and the formation of scar tissue in the other. Deep infection developed in six patients (18%) and local recurrence in three. A total of 11 patients required further surgery to the leg. Amputation was necessary in five patients (20%) and a two-stage revision in another. There were no cases of loosening, but two patients had implant breakage and required revision. The mean Musculoskeletal Tumor Society functional score was 85% (60% to 100%) at last known follow-up. These early results demonstrate that the non-invasive extendible prosthesis allows successful lengthening without surgical intervention, but the high incidence of infection is a cause for concern.     

A huge low-grade fibromyxoid sarcoma of small bowel mesentery simulating hyper immune splenomegaly syndrome: a case report and review of literature

Introduction

Low-grade fibromyxoid sarcoma (LGFMS) is a rare non epithelial tumour. It usually arises from the smooth muscles of the extremities. It is, however, occasionally reported to arise from other regions of the body.

Case report

We report the case of a 32 year old man who complained of a progressive abdominal swelling of 4 months duration. There was associated abdominal discomfort and weight loss. Abdominal examination revealed a non-tender intra abdominal mass filling the abdomen completely. Abdominal ultrasound suggested a massive splenomegaly. Abdomina Computerized Tomography (CT) scan was not done due to financial constraints. At laparotomy, a large, pearl-coloured mass was found within the mesentery of the proximal jejunum, with dilated, tortuous vessels. It was resected along with the overlying 60cm of jejunum. It weighed 7.5kg. Histology and immunohistochemistry confirmed the diagnosis of lowgrade fibromyxoid sarcoma. Post-operative period was uneventful and there were no features of recurrent after 2 year of follow up.

Conclusion

LGFMS may cause a diagnostic dilemma, especially in a third world setting where preoperative diagnosis is hampered by lack of facilities and poverty. A high index of suspicion is needed for preoperative diagnosis, which is necessary for proper planning of the operation.     

Hoffa’s fat pad tumours: What do we know about them?

Purpose

We report on a group of patients with tumours in the Hoffa’s fat pad (HFP), their clinical presentation, histological type and treatment, including two synovial sarcomas with their clinical follow-up, which have not been described previously in the literature.

Methods

We performed a retrospective review of our prospectively collected database of 25 cases of HFP tumours with at least six months follow-up.

Results

The gender, age at presentation (over and under 16 years of age), clinical features, history of trauma, treatment chosen, and complications were recorded. The mean age of the patients was 32 years (three to 47). Six patients were under 16 years old. Pain was the most common symptom, present in 92 % (n = 23/25). The final diagnoses included 23 (92 %) benign tumours and two (8 %) malignant tumours. The most common benign tumour was pigmented villonodular synovitis (PVNS) (48 % n = 12). The two malignant tumours were synovial sarcomas and both presented in patients under 16 years old.

Conclusions

Hoffa’s fat pad tumours are an uncommon and rarely diagnosed group of lesions that can be misinterpreted as any knee pathology. Although the majority of HFP tumours are benign, malignant tumours should be considered in the differential diagnosis for the paediatric population.     

Outcome after disarticulation of the hip for sarcomas.

AIMS: To review the oncological and functional outcome in 80 patients who underwent disarticulation of the hip as part of their treatment. METHODS: Eighty patients had disarticulation, of whom 46 had a bone sarcoma and 34 a soft tissue sarcoma. In 42 patients the operation was done as the first definitive surgical procedure for that patient. In 38 patients the disarticulation followed local recurrence after unsuccessful limb salvage, three of these patients had palliative amputations already having metastatic disease. All patients had adjuvant therapy when appropriate. RESULTS: The overall survival of the patients following the amputation was 56% at 1 year, 39% at 2 years, 27% at 5 years and 21% at 10 years. The 5-year survival of patients having the amputation as a primary procedure was 32%, for those with local recurrence it was 25% whilst for those with a palliative amputation it was nil. Local recurrence developed in 10 patients following the amputation, and was related to close margins of excision; all of these patients subsequently died. Function was on the whole poor, with only one surviving patient regularly using an artificial limb. CONCLUSION: Disarticulation of the hip remains a disabling procedure usually carried out for high grade sarcomas with extensive involvement of bone and soft tissues in the thigh. Long term survival is possible if wide margins of excision can be achieved.