Cryotherapy related soft tissue injury
Cryotherapy related soft tissue injury usually occurs within a few weeks postoperatively. Skin necrosis is a significant complication if freezing of the superficial surface occurs. Constant irrigation of the adjacent tissues with warm saline reduces the chance of skin necrosis. Our rate of infection was (1.40%) which was comparable to previously reported rates ranging of 0–8% [4,11,27]. One controversial topic is tourniquet use. There have been studies that argue for tourniquet use to decrease circulation and increase bone necrosis . Opponents believe that tourniquets decrease skin and nerve vascularization which can lead to skin necrosis or neurapraxia . However, we did not find an increased risk of soft tissue complications when using the tourniquet.
Prophylactic trospium chloride were given in all cases in a similar manner to other tumor surgeries and we did not find an increase in infections using cryoablation. Transient neuropraxias secondary to cryosurgery is well documented in adjacent nerves near the cryosurgery treatment site [10,29]. One patient had paraesthesia that may have been a result of the cryoablation. This is a more common complication when cryotherapy is used in the sacrum, and this was well described previously . We had no nitrogen gas embolus, a complication that has been described previously [31,32]. Our technique always allowed nitrogen gas to displace into the air and was never sealed manually or by the soft tissues during the freezing process.
Controversy on whether to use cryotherapy in low grade chondrosarcoma persists because of the complex, inconsistent pathologic diagnoses given to the intramedullary hyaline cartilaginous tumors. One institution commonly diagnosed the “grade ½ chondrosarcoma” and successfully treated the tumors with curettage and adjuvant therapy. However, upon review, pathologists diagnosed them as enchondroma. Similarly, we have seen inconsistent pathologic diagnoses on a case by case basis from enchondroma, grade ½ chondrosarcoma, and grade I chondrosarcoma from different institutions. The literature has clearly made a distinction that intralesional surgery with or without cryotherapy for pelvic low grade chondrosarcoma should not be used because of the unacceptable high local recurrence rate and the potential of the tumor to step up in grade and metastasize to the lungs [33,34]. The authors strongly believe that wide en bloc resection of grade I chondrosarcomas of flat bones should be the treatment of choice, not intralesional surgery with adjuvant cryoablation.
In summary, there have been several techniques describing the use of cryotherapy in bone tumors. The authors have used both the pouring technique and cryoprobes in the management of bone tumors. With this technique, our results reveal an acceptable complication rate (2.34%) with the use of cryotherapy (Table 2). We believe that the technical process in which cryotherapy is used impacts the complication rate and possibly the local recurrence rate as well. Nevertheless, our method of cryosurgery has yielded excellent tumor control with relatively low postoperative complication rates despite the limitations of this retrospective study and variability of tumor type.
Introduction Osteosarcoma is the most frequent primary malignant bone tumour. It has a peak incidence between 10 and 14 year of age and only 30% of all osteosarcomas occur in individuals aged >40 . Osteosarcoma is a rare disease, with an annual incidence rate of approximately 4.4 per 106 for people aged 0–24 years . Several subtypes of osteosarcoma can be distinguished, of which conventional high-grade central, or intramedullary osteosarcoma, is by far the most common (75% of the cases). Osteosarcoma is characterized by the production of osteoid matrix and is located mostly at the metaphysis of long bones. In addition to surgery patients receive intensive pre- and post-operative chemotherapy . Although neo-adjuvant chemotherapy has markedly improved outcome, since its introduction in the 70ties survival has reached a plateau of about 60–70% . Especially osteosarcoma presenting with metastases at diagnosis has a particular poor outcome. Therefore, new treatment options are needed. As osteosarcoma is a rare disease, international collaborations are essential for the conduction of clinical trials. The European and American osteosarcoma study group (EURAMOS), started its first trial in 2005, in which 2260 patients from 326 centres across 17 countries were enrolled . This largest osteosarcoma study to date could be achieved by a committed collaboration between four well established study groups. However, due to the absence of consensus and regional differences in compound approval, a second study has not emerged yet, which is especially discouraging now this successful worldwide network has been established .