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Rita Kandel

Publications and source records attributed to Rita Kandel.

6 recordsLinked to original sources
PubMed2003

Misclassification in a matched case-control study with variable matching ratio: application to a study of c-erbB-2 overexpression and breast cancer.

We provide a simple analytic correction for risk factor misclassification in a matched case-control study with variable numbers of controls per case. The method is an extension of existing methodology, and involves estimating the corrected proportions of controls and cases in risk factor categories within each matched set. These estimates are then used to calculate the Mantel-Haenszel odds ratio estimate corrected for misclassification. A simulation-based interval estimate is developed. An example is given from a study of risk factors for progression of benign breast disease to breast cancer, in which the risk factor is a biological marker measured with poor sensitivity.

Breast Neoplasms↗
PubMed2003

Low-grade liposarcoma with osteosarcomatous dedifferentiation: radiological and histological features.

We describe the radiological and pathological findings of a rare case of a low-grade liposarcoma associated with a high-grade osteosarcomatous component in a 78-year-old woman. Pre-operative imaging demonstrated a well-encapsulated homogeneous fatty tumour in the right buttock deep to the gluteal musculature. Centrally within the fatty tumour a region of increased soft tissue attenuation on CT and heterogeneous high signal on fat-saturated T2-weighted MRI was seen with amorphous calcification/ossification. Histological assessment revealed a low-grade liposarcoma containing an area of dedifferentiation that resembled an osteosarcoma. We describe the radiological-pathological findings in this rarely reported clinical entity and discuss the differential diagnosis of calcification within lipomatous tumours.

Aged↗
PubMed2003

Cyclin alterations in giant cell tumor of bone.

Cyclins play an important role in regulating the passage of dividing cells through critical checkpoints in the cell cycle. Because alterations of several cyclins, especially cyclin D1, have been implicated in the development of many human neoplasms, we examined 32 cases of giant cell tumor of long bones for cyclin D1 gene amplification and protein overexpression using differential polymerase chain reaction and immunohistochemistry, respectively. In addition, the expression of cyclin D3, cyclin B1, and the proliferation-associated antigen Ki-67 (MIB-1) was assessed immunohistochemically. Low-level cyclin D1 gene amplification was detected in 61% of giant cell tumor cases. All tumors showed cyclin D1, cyclin D3, cyclin B1, and Ki-67 (MIB-1) staining; however, the distribution was very characteristic. Cyclin D1 protein expression was seen predominantly in the nuclei of the giant cells, with occasional mononuclear cells staining. There was no correlation between cyclin D1 gene amplification and protein overexpression. Cyclin D3 staining showed a similar distribution, with 88% of cases showing protein overexpression. Cyclin D1 and/or D3 staining in the giant cells was never associated with staining for either cyclin B1 or Ki-67 (MIB-1), as the expression of the latter two proteins was restricted to the mononuclear cells. Cyclin B1 overexpression was seen in 44% of cases. Ki-67 (MIB-1) staining was present in all cases, and between 10 to 50% of the mononuclear cells were positive. These results suggest that alterations in cyclin D1 and/or D3 might play a role in the pathogenesis of giant cell tumor of bone.

Adolescent↗
PubMed2002

Preoperative versus postoperative radiotherapy in soft-tissue sarcoma of the limbs: a randomised trial.

BACKGROUND: External-beam radiotherapy (delivered either preoperatively or postoperatively) is frequently used in local management of sarcomas in the soft tissue of limbs, but the two approaches differ substantially in their potential toxic effects. We aimed to determine whether the timing of external-beam radiotherapy affected the number of wound healing complications in soft-tissue sarcoma in the limbs of adults. METHODS: After stratification by tumour size (< or = 10 cm or >10 cm), we randomly allocated 94 patients to preoperative radiotherapy (50 Gy in 25 fractions) and 96 to postoperative radiotherapy (66 Gy in 33 fractions). The primary endpoint was rate of wound complications within 120 days of surgery. Analyses were per protocol for primary outcomes and by intention to treat for secondary outcomes. FINDINGS: Median follow-up was 3.3 years (range 0.27-5.6). Four patients, all in the preoperative group, did not undergo protocol surgery and were not evaluable for the primary outcome. Of those patients who were eligible and evaluable, wound complications were recorded in 31 (35%) of 88 in the preoperative group and 16 (17%) of 94 in the postoperative group (difference 18% [95% CI 5-30], p=0.01). Tumour size and anatomical site were also significant risk factors in multivariate analysis. Overall survival was slightly better in patients who had preoperative radiotherapy than in those who had postoperative treatment (p=0.0481). INTERPRETATION: Because preoperative radiotherapy is associated with a greater risk of wound complications than postoperative radiotherapy, the choice of regimen for patients with soft-tissue sarcoma should take into account the timing of surgery and radiotherapy, and the size and anatomical site of the tumour.

Aged↗