Management of Osteoid Osteoma in Unusual Locations

PURPOSE OF THE STUDY Osteoid osteoma is a benign tumor that forms in bone, which accounts for 3% of all primary bone tumors. The classical clinical finding is substantial nocturnal pain and imaging findings. The management of osteoid osteomas include open surgical excision or minimally invasive percutaneous interventions. Why and which treatment modality should be considered between CT-guided radiofrequency ablation and open surgical excision for osteoid osteomas in unusual locations? MATERIAL AND METHODS We retrospectively reviewed 17 patients with osteoid osteomas in unusual locations included cuboid, triquetrum, coronoid process, and proximal phalanx. We evaluated the duration from symptoms to diagnosis, activity related pain, clinical findings, and possible recurrence or complications. The minimum clinical follow-up was 51 ± 34.8 months. RESULTS CT-guided radiofrequency ablation was applied to 3 patients and open surgical excision procedures to 14. All the complaints of patients gone after treatment. No major complications were observed following CT-guided radiofrequency ablation or surgical excision. Transient weakness/paresthesia was determined in 1 patient in the treated shoulder after CT-guided radiofrequency ablation, which resolved spontaneously in the 6th week. There was only recurrence seen in 1 patient, who had 2nd proximal phalangeal osteoid osteoma. Proximal interphalangeal joint arthrodesis was performed after recurred lesion. DISCUSSION The main challenge in management of the osteoid osteomas of the unusual locations are the diagnosis. When we examined the literature, the interval from the beginning of the symptoms to accurate diagnosis did not change over the past decades. Techniques for management of these lesions should be chosen with consideration of the location of the lesion. CONCLUSIONS If there is long-term complaint of undiagnosed limb pain, the physician should suspect osteoid osteoma. However, the selection of treatment modality should be considered according to the location of the lesion. Which management modality is superior may change depending on the location of the lesion between CT-guided radiofrequency ablation and surgical excision. Key words: osteoid osteoma, unusual locations, CT guided, radiofrequency ablation, benign bone tumor.

Prognostic importance of RASSF2 expression in patients with gastric cancer who had undergone radical gastrectomy

BACKGROUND

Although Ras-association domain family of gene 2 (RASSF2) has been shown to undergo promoter methylation at high frequency in some cancer types and in brain metastases, its clinical utility as a useful prognostic molecular marker remains unclear in gastric cancer.

METHODS

Prognostic significance of RASSF2 expression was retrospectively analysed by immunohistochemically in 105 patients with gastric cancer who underwent curative gastrectomy.

RESULTS

Low RASSF2 expression was detected in 58 (55 %) patients, whereas 47 patients (45 %) had high RASSF2 expression. Lymph node involvement, pT stage, TNM stage, vascular invasion, perineural invasion and the presence of recurrence were found to be significantly related to RASSF2 expression levels. Low PRL-3 expression was closely correlated with lymph node metastasis (p = 0.001), advanced pT stage (p = 0.021), advanced TNM stage (p < 0.001), the presence of vascular invasion (p < 0.001), perineural invasion (p = 0.018) and high prevalence of recurrence (p = 0.003) compared with high RASSF2 expression. The median disease-free survival (DFS) time for patients with low RASSF2 expression was significantly worse than that of patients with high RASSF2 expression (10.2 vs. 50.6 months, p < 0.001). In addition, patients with high RASSF2 expression had the higher overall survival (OS) interval compared to patients with low RASSF2 expression (NR vs. 14.9 months, p < 0.001). In the multivariate analysis, the rate of RASSF2 expression levels was an independent prognostic factor, for DFS [p < 0.001, HR 0.12 (0.10-0.88)] and OS [p < 0.001, HR 0.10 (0.04-0.46)], as were pT stage and TNM stage, respectively.

CONCLUSIONS

RASSF2 may be an important molecular marker for carcinogenesis, prognosis and progression in gastric cancer, but the potential value of RASSF2 expression as a useful molecular marker in gastric cancer progression should be evaluated, comprehensively. It would be possible to develop treatments targeting RASSF2 and advance new treatment strategies for gastric cancer.