5-ALA-mediated fluorescence of musculoskeletal tumors in a chick chorio-allantoic membrane model: preclinical in vivo qualification analysis as a fluorescence-guided surgery agent in Orthopedic Oncology

Background Fluorescence-guided surgery (FGS) with 5-aminolevulinic acid (5-ALA) and other contrast agents has shown its efficacy in improving resection margins, local recurrence and survival rates in several medical disciplines. It is the objective of this study to analyze the engraftment rate of musculoskeletal tumor specimens on the chick chorio-allantoic membrane (CAM), the rate of tumor fluorescence (PDD), and the effects of photodynamic therapy (PDT) after exposure of tumors to 5-ALA in an in vivo environment. Methods A total of 486 CAMs were inoculated with macroscopic tumor grafts (n = 26; n = 478 eggs) and primary cell culture suspensions (n = 2; n = 8 eggs) from 26 patients on day 10 of egg development. On day 16, 2 mg/200 µl 5-ALA were topically applied per egg. After 4 h of incubation, Protoporphyrin IX was excited using blue light (420 ± 10 nm). Tumor fluorescence (PDD) was photo-documented. A subgroup of specimens was additionally exposed to red light (635 nm ± 10 nm; PDT). After the termination of the experiment, CAM-grown tumors were histopathologically analyzed. Results Benign and borderline tumors (chondroblastoma, giant cell tumor of bone and atypical chondrogenic tumor) presented with high rates of detectable fluorescence. Comparable results were found for chondrosarcoma, osteosarcoma and Ewing’s sarcoma among bone and dedifferentiated liposarcoma, myxofibrosarcoma and undifferentiated pleomorphic sarcoma among soft tissue sarcomas. Overall, tumor fluorescence was negative for 20.2%, single-positive (+) for 46.9% and double-positive (++) for 32.9% of macroscopic xenografts, and negative in 20% and (+) in 80% of primary cell culture tumors. Macroscopic tumor xenografts (n = 478) were identified as viable in 14.8%, partially viable in 2.9% and partially to completely regressive in 45.2%. All (n = 8) tumors grown from primary cell culture were viable. After PDT, tumor samples were found viable in 5.5%, partially viable in 5.5% and partially to completely regressive in 68%. Egg survival increased with decreasing PDT doses. Conclusions The CAM model proves to be a suitable in vivo model for the investigation of short-term observation questions in musculoskeletal tumors. The findings of this study warrant further investigation of PDT effects on musculoskeletal tumors and a possible incorporation of 5-ALA FGS in clinical Orthopedic Oncology care.

PET–CT for the diagnosis and treatment of primary musculoskeletal tumors in Chinese patients - experience from 255 patients in a single center

Objective: The current study was carried out to assess the value of positron emission tomography (PET)/CT on the diagnosis and staging of primary musculoskeletal tumors. Methods: PET–CT test results and histopathological study reports of all the patients with primary musculoskeletal tumors in our department from January 2006 to July 2015 were retrospectively reviewed. Maximum standardized uptake value (SUVmax) in these PET–CT reports were recorded and analyzed respectively for each type of sarcoma. Results: A total of 255 patients were included in the final analysis. Sensitivity of SUVmax based diagnosis was 96.6% for primary malignant osseous sarcomas and 91.2% for soft tissue sarcomas. SUVmax of high-grade osseous sarcomas (average 8.4 ± 5.5) was significantly higher (p < 0.001) than low-grade osseous sarcomas (average 3.9 ± 1.8); based on current case series, SUVmax of high-grade soft tissue sarcomas (7.5 ± 5.1) was not significantly different (p = 0.229) from that of low-grade soft tissue sarcomas (5.3 ± 3.7). Significant decrease of SUVmax value after chemotherapy was associated with favorable prognosis in patients with osteosarcoma. Conclusion: Results of the current study indicate that, the SUVmax based application of PET–CT can be a valuable supplementary method to histopathological tests regarding the diagnosis and staging of primary musculoskeletal sarcomas. Advances in knowledge: SUVmax based application of PET–CT is a highly sensitive method in diagnosis of primary osseous and soft tissue sarcomas in Chinese patients.

The Use of Mobile Applications for the Diagnosis and Treatment of Tumors in Orthopaedic Oncology – a Systematic Review

The use of smartphone apps is an essential part of everyday life. Mobile applications offer enormous opportunities for dealing with challenges in public health, and their number increases every day. This paper aims to review the existing literature on mobile applications in orthopaedic oncology and to summarize the current mobile applications for musculoskeletal tumors. A systematic literature review was conducted regarding articles on mobile applications in orthopaedic and trauma surgery. The focus was on identifying mobile applications that can be used in the treatment of patients with musculoskeletal tumors. Two reviewers independently assessed study eligibility, extracted data, and appraised methodological quality. In addition, the Apple App Store and Google Play Store were searched for suitable mobile applications. Ninety-one articles describing a mobile application in orthopaedic and trauma surgery were identified. Three articles focused on a mobile application for musculoskeletal tumors. Additionally, seven mobile applications were available in the App/Play Stores dealing with bone or soft tissue tumors in orthopaedic oncology without corresponding scientific articles. Increasing numbers of mobile applications are being developed in orthopaedic and trauma surgery. Currently, only three scientific articles on mobile applications in orthopaedic oncology are present, yet several more applications are available without scientific medical evaluation. Since mobile applications can facilitate the everyday life of orthopaedic and trauma surgeons, it is worthwhile to be aware of new developments in this field. A regular scientific evaluation of the subject is important in order to classify the significance of these applications.