Clinical Applications of FDG-Probe Guided Surgery

Background : For a definitive diagnosis in many oncological, inflammatory and infectious diseases histological examination is required. Non-palpable lesions detected with PET/CT scanning that cannot be localized with conventional imaging methods can be localized and excised using FDG-probe guided surgery. We describe the application of FDG-probe guided surgery in 9 patients.

Methods : The application of FDG-probe guided surgery used in 9 consecutive patients with oncological and infectious diseases is described. Four hours before surgery, 3.5 MBq/Kg body weight FDG was intravenously administered after which a FDG-PET-scan was performed to confirm the FDG-avid lesion(s). The lesions with highest activity were detected with the FDG-probe and the lesions were subsequently excised and sent for histopathological examination. Results : In all of the 9 cases the target lesion was successfully identified and subsequently removed. When multiple and/or macroscopically normal lymph nodes were found, the use of the FDG-probe allowed selection of the PET-avid lymph nodes for resection.

Conclusion : FDG-probe guided surgery is a relatively simple surgical technique to identify and excise FDG-accumu-lating suspicious lesions in oncological, inflammatory and infectious diseases.     

The constrictor knot is the best ligature

Introduction

An ideal ligature should tighten readily and remain tight. Ligature failure can be a critical complication of invasive procedures in human and veterinary surgical practice. Previous studies have tested various knots but not the constrictor knot.

Methods

A new test bench was employed to compare six ligatures using four suture materials. As tension in a ligature is not readily measured, the study employed a surrogate measurement: the force required to slide a ligature along a rod. Benchmark values tested each suture material wrapped around the rod to establish the ratio between this force and the ligature tension for each material. Each ligature was tested first during tightening and then again afterwards. The benchmark ratios were employed to calculate the tensions to evaluate which ligature and which suture material retained tension best.

Results

The model provided consistent linear relationships between the tension in the suture and the force required to pull the ligature along the rod. The constrictor knot retained tension in the ligature best (55–107% better than the next best ligature). Among the suture materials, polydioxanone had the greatest ability to retain the tension in a ligature and polyglactin the least.

Conclusions

The constrictor knot showed superior characteristics for use as a ligature, and should be introduced into teaching and clinical practice for human and veterinary surgery. The new test bench is recommended for future testing of ligatures as well as objective comparison of suture materials.     

Comparison of patient reported outcomes after Triathlon? and Kinemax Plus prostheses

INTRODUCTION

The Triathlon^® (Stryker, Kalamazoo, MI, US) total knee replacement was designed to improve patient function and survivorship. The aim of this study was to determine whether the Triathlon^® prosthesis produces better patient reported outcomes than a previous design by the same manufacturer, the Kinemax Plus.

METHODS

The outcome of 233 knees of patients with a mean age of 68 years (range: 40–80 years) who received the Kinemax Plus prosthesis were compared with the outcomes of 220 knees of patients with a mean age of 70 years (range: 42–90 years) who received the Triathlon^® prosthesis. Data were collected via postal questionnaire prior to surgery as well as at 8–12 weeks and at 1 year following surgery. Validated questionnaires were used including the WOMAC^® (Western Ontario and McMaster Universities) pain and function scales, the Knee injury and Osteoarthritis Outcome Score quality of life scale and the self-administered patient satisfaction scale.

RESULTS

This study found that patients who had the Triathlon^® prosthesis had significantly better pain relief (p<0.0001), function (p=0.028), knee related quality of life (p<0.0001) and satisfaction (p=0.0003) at three months after surgery than those who received the Kinemax Plus prosthesis. In addition, knee related quality of life (p=0.002) and satisfaction (p=0.021) were significantly higher at one year after surgery in Triathlon^® patients.

CONCLUSIONS

The findings suggest that return to function and reduction in pain may occur more quickly in patients with a Triathlon^® prosthesis than in those with the Kinemax Plus.     

i(12p)-negative testicular germ cell tumors. A different group?

Cytogenetic analysis was performed of three seminomas, two primary nonseminomas, and two mature residual teratomas following chemotherapy, all lacking i(12p). Testicular germ cell tumors without an i(12p) may represent a subgroup of germ cell tumors, also in their clinical course, compared with those having i(12p).     

Involvement of E-cadherin and beta-catenin in germ cell tumours and in normal male fetal germ cell development

Intercellular contacts, mediated by E-cadherin, are essential for germ cell migration and maturation. Furthermore, it has been suggested that decrease or loss of E-cadherin correlates with tumour progression and invasive behaviour. beta-catenin is involved in a number of different processes, including cell--cell interaction when bound to cadherins, and determination of cell fate in pluripotent cells when activated via the Wnt signal-transduction pathway. To shed more light on the role of these factors in normal fetal germ cell development and the pathogenesis of germ cell tumours (GCTs), the present study investigated the presence and localization of E-cadherin and beta-catenin by immunohistochemistry. E-cadherin was only weakly expressed in or absent from fetal germ cells of the second and third trimesters, and was not expressed in carcinoma in situ/intratubular germ cell neoplasia unclassified (CIS/ITGCNU) and gonadoblastoma, the precursor of an invasive GCT in dysgenetic gonads. In GCTs, it was generally not expressed in seminoma and dysgerminoma, but was found in the vast majority of non-seminoma cells. beta-catenin was found in the cytoplasm of fetal germ cells at all gestational ages and in spermatogenesis in post-pubertal testes. It was also present in CIS/ITGCNU and gonadoblastoma. Whereas seminomas and dysgerminoma were negative, non-seminoma cells were frequently found to express beta-catenin. Expression of both factors therefore reflects the degree of differentiation of these tumours. No differences for either E-cadherin or beta-catenin were observed between samples of tumours resistant or sensitive to chemotherapy, and E-cadherin expression did not correlate with vascular invasion. E-cadherin and beta-catenin therefore play a role in both normal and malignant germ cell development and differentiation that warrants further investigation, but they seem to be of limited value as predictive or prognostic factors in GCTs.     

Microduplication of Xp11.23p11.3 with effects on cognition,behavior, and craniofacial development

El‐Hattab AW, Bournat J, Eng PA, Wu JBS, Walker BA, Stankiewicz P, Cheung SW, Brown CW. Microduplication of Xp11.23p11.3 with effects on cognition, behavior, and craniofacial development. We report an ～1.3 Mb tandem duplication at Xp11.23p11.3 in an 11‐year‐old boy with pleasant personality, hyperactivity, learning and visual‐spatial difficulties, relative microcephaly, long face, stellate iris pattern, and periorbital fullness. This clinical presentation is milder and distinct from that of patients with partially overlapping Xp11.22p11.23 duplications which have been described in males and females with intellectual disability, language delay, autistic behaviors, and seizures. The duplicated region harbors three known X‐linked mental retardation genes: FTSJ1, ZNF81, and SYN1. Quantitative polymerase chain reaction from whole blood total RNA showed increased expression of three genes located in the duplicated region: EBP, WDR13, and ZNF81. Thus, over‐expression of genes in the interval may contribute to the observed phenotype. Many of the features seen in this patient are present in individuals with Williams‐Beuren syndrome (WBS). Interestingly, the SYN1 gene within the duplicated interval, as well as the STX1A gene, within the WBS critical region, co‐localize to presynaptic active zones, and play important roles in neurotransmitter release.     

A novel SRY missense mutation affecting nuclear import in a 46,XY female patient with bilateral gonadoblastoma

Patients with disorders of sex development (DSD), especially those with gonadal dysgenesis and hypovirilization, are at risk of developing the so-called type II germ cell tumors (GCTs). Both carcinoma in situ and gonadoblastoma (GB) can be the precursor lesion, resulting in a seminomatous or non-seminomatous invasive cancer. SRY mutations residing in the HMG domain are found in 10–15% of 46,XY gonadal dysgenesis cases. This domain contains two nuclear localization signals (NLSs). In this study, we report a unique case of a phenotypical normal woman, diagnosed as a patient with 46,XY gonadal dysgenesis, with an NLS missense mutation, on the basis of the histological diagnosis of a unilateral GB. The normal role of SRY in gonadal development is the upregulation of SOX9 expression. The premalignant lesion of the initially removed gonad was positive for OCT3/4, TSPY and stem cell factor in germ cells, and for FOXL2 in the stromal component (ie, granulosa cells), but not for SOX9. On the basis of these findings, prophylactical gonadectomy of the other gonad was performed, also showing a GB lesion positive for both FOXL2 (ovary) and SOX9 (testis). The identified W70L mutation in the SRY gene resulted in a 50% reduction in the nuclear accumulation of the mutant protein compared with wild type. This likely explains the diminished SOX9 expression, and therefore the lack of proper Sertoli cell differentiation during development. This case shows the value of the proper diagnosis of human GCTs in identification of patients with DSD, which allows subsequent early diagnosis and prevention of the development of an invasive cancer, likely to be treated by chemotherapy at young age.