99mTc-tetrofosmin scintigraphy in musculoskeletal tumours: the relationship between P-glycoprotein expression and tetrofosmin uptake in malignant lesions.

The aims of this study were to assess the role of (99m)Tc-tetrofosmin scintigraphy in the diagnosis of malignant vs. benign musculoskeletal tumours and to determine the relationship between P-glycoprotein expression and tetrofosmin uptake in malignant lesions. Forty-six patients (32 malignant, 14 benign) with various musculoskeletal lesions were studied. Each patient underwent (99m)Tc-methylene diphosphonate three-phase bone scanning initially. At least 2 days later, dynamic and static (99m)Tc-tetrofosmin scans were obtained. The tetrofosmin scans were evaluated by visual and quantitative analysis. The count ratio of the lesion to the contralateral normal area (uptake ratio, UR) was calculated from the region of interest drawn on the tetrofosmin scan. The lesions were then resected by open biopsy to obtain a histopathological diagnosis. P-glycoprotein levels were determined immunohistochemically in 22 of 32 malignant lesions. A significant difference between the mean UR values of benign and malignant lesions was found (1.36 +/- 0.47 vs. 3.35 +/- 2.08, P = 0.000). Visual analysis showed an accuracy of 85%, and the accuracy of the quantitative analysis was 87% with the threshold level of UR as 1.76. When perfusion findings were added to the evaluation criteria, the accuracies of visual and quantitative analysis were increased to 87% and 89%, respectively. The relationship between the levels of P-glycoprotein and the UR values of tetrofosmin was not statistically significant (r = -0.235, P = 0.2). In addition, the mean UR value of the patients with P-glycoprotein expression was not statistically different from that of the patients without P-glycoprotein expression (3.01 +/- 1.48 vs. 4.27 +/- 2.90, P = 0.297). In conclusion, visually significant tetrofosmin uptake and increased perfusion in a musculoskeletal lesion strongly suggest that the lesion is malignant (positive predictive value, 96%). P-glycoprotein expression was not found to be a major factor interfering with 30 min tetrofosmin uptake in a malignant musculoskeletal lesion. However, the relatively high false-negative rate among negative results (28%) limits the value of (99m)Tc-tetrofosmin scintigraphy as a single diagnostic tool in differentiating between benign and malignant musculoskeletal tumours.

The use of recombinant human granulocyte colony-stimulating factor in combination with single or fractionated doses of ifosfamide and doxorubicin in patients with advanced soft tissue sarcoma.

Sixty patients with stage III-B and IV soft tissue sarcomas were randomized to receive either ifosfamide 5 g/m2xdx1 and doxorubicin 60 mg/m2xdx1 given every 3 weeks (arm A) or ifosfamide 1.8 g/m2xdx5 and doxorubicin 60 mg/m2xdx1 given every 4 weeks (arm B). Recombinant human granulocyte colony-stimulating factor (r-met Hu G-CSF: 250 micrograms/m2xd) was applied with a prophylactic intent to patients in arm A only. The response rate was higher in arm A patients (56% versus 33%, p = 0.03). In stage III patients, the complete response rate was significantly higher (53% versus, 13.3%, p = 0.01) and the duration of response was significantly longer in arm A (20 +/- 8.2 months versus, 13.4 +/- 7 months, p = 0.05). Chemotherapy related myelotoxicity and mucositis were also less frequent in this arm as a result of prophylactic r-met Hu G-CSF administration (p = 0.04, p = 0.003). It was concluded that single dose ifosfamide and doxorubicin combinations deserve further investigation under the cover of hematopoietic growth factors, particularly in patients with stage III soft tissue sarcomas.

Congenital insensitivity to pain with anhidrosis. A case report.

We present a five-year-old girl with congenital insensitivity to pain with anhidrosis. A skeletal radiographic survey revealed several old fractures. Application of pilocarpine showed anhidrosis and nerve biopsy revealed a significant decrease in the number of myelinated and unmyelinated nerve fibres.