Enhancement characteristics of retroperitoneal lymphomatous lymph nodes.

BACKGROUND: Previous studies of CT enhancement of lymphomatous lymph nodes (LLN) of the neck and the mediastinum showed that the LLN had lower enhancement values than normal lymph nodes. PURPOSE: To elucidate the contrast medium enhancement curves of LLN in the retroperitoneum by comparing the curves of LLN with those of normal lymph nodes, to test whether differences between these curves could be of diagnostic value, and to compare the present enhancement curves of LLN of the retroperitoneum with the curves of LLN of the neck and the mediastinum from previous similar investigations. MATERIAL AND METHODS: Twenty-eight consecutive patients with LLN of the retroperitoneum (three with Hodgkin's lymphoma [HL]) and 21 control patients with sarcomas and thus presumably normal retroperitoneal nodes underwent dynamic CT examinations. The previous, similar investigation of lymph nodes of the neck comprised 28 patients with LLN and the investigation of mediastinal lymph nodes comprised 24 patients with LLN. RESULTS: The enhancement curves of the retroperitoneal LLN had significantly lower attenuation than those of the retroperitoneal control nodes. A combination of peak contrast value and time to peak adjusted to total body weight yielded a diagnostic accuracy which at the best showed a sensitivity of 90.5% with a specificity of 82.6%. The LLN of the retroperitoneum had higher attenuation values than corresponding nodes of the mediastinum but no significant difference was found between LLN of the retroperitoneum and LLN of the neck in previous similar investigations. CONCLUSION: The comparison of enhancement curves of retroperitoneal LLN with retroperitoneal control nodes showed a marked similarity with and substantiates our previous findings in lymph nodes of the neck and of the mediastinum. The best diagnostic accuracy was achieved by combining the parameters peak contrast value and time to peak and adjusting these values to the body weight. Peak enhancement of the retroperitoneal LLN was higher and arrived earlier than that of the mediastinal nodes from the previous investigation.

Enhancement characteristics of lymphomatous lymph nodes of the mediastinum.

BACKGROUND: Previous studies of CT enhancement of lymphomatous lymph nodes (LLN) of the neck showed that the LLN had lower enhancement values than normal lymph nodes. PURPOSE: To elucidate the contrast medium enhancement curves of LLN in the mediastinum by comparing the curves of LLN with those of normal lymph nodes, and to compare the present enhancement curves of LLN of the mediastinum with the curves of LLN of the neck from a previous similar investigation. MATERIAL AND METHODS: Twenty-four consecutive patients with LLN in the mediastinum (9 with Hodgkin's lymphoma [HL]) and 23 control patients with sarcomas and thus presumably normal mediastinal nodes underwent dynamic CT examinations. The previous, similar investigation of lymph nodes of the neck comprised 28 patients with LLN and 20 control patients. RESULTS: The enhancement curves of the mediastinal LLN had significantly lower values than those of the mediastinal control nodes. The LLN of the mediastinum had lower mean peak contrast values than the corresponding nodes of the neck from a previous investigation. CONCLUSION: The comparison of enhancement curves of mediastinal LLN with mediastinal control nodes showed a marked similarity with and substantiates our previous findings in lymph nodes of the neck.

Enhancement characteristics of lymphomatous lymph nodes of the neck.

BACKGROUND: Previous studies of computed tomography (CT) enhancement of lymphomatous lymph nodes suggest that these nodes might have lower post contrast attenuation values than normal lymph nodes. We have previously found that the contrast medium enhancement curves of lymphomatous lymph nodes of the neck had significantly lower enhancement than those of presumably normal lymph nodes. PURPOSE: To prospectively compare CT contrast medium enhancement curves of a homogeneous population of 28 patients with lymphomatous lymph nodes of the neck with 20 controls; to compare enhancement curves before and after successful treatment and to compare nodes with Hodgkin lymphoma (HL) and nodes with non-Hodgkin lymphoma (NHL). MATERIAL AND METHODS: Twenty-eight consecutive patients (12 with HL) with lymphomatous lymph nodes of the neck and 20 control patients with sarcomas and presumably normal neck nodes underwent dynamic CT examinations. Seventeen of the patients in complete remission after lymphoma treatment were also examined. RESULTS: The lymphomatous lymph nodes had significantly lower mean enhancement values than those of the control group (mean HU value at 90 s 77.9+/-10.5 HU and 93.4+/-15.3 HU, respectively, sensitivity 91% for values <92 HU at 90 s). Late enhancement values in the treated patients were significantly higher than those in the untreated patients. Patients with HL and patients with NHL had similar enhancement curves except that those with NHL had higher values at 7 min. No significant difference in mean percentage loss of enhancement was found between normal nodes and lymph nodes with HL before treatment, but there was a slightly significant difference between normal nodes and lymph nodes with NHL. No significant difference in percentage loss of enhancement was found between normal nodes and lymphomatous lymph nodes after treatment. CONCLUSION: Dynamic CT examinations showed that lymphomatous lymph nodes had significantly lower mean enhancement values than those of the control group and confirmed the findings from a pilot study. Before treatment the mean enhancement values of HL were significantly higher than those of NHL at 7 min. There was no significant difference between the curves after treatment.

Effects of growth factors on growth and radiation sensitivity of the human breast cancer cell line T-47D.

Different growth factors are supposed to be involved in evolution of breast cancer. Radiation therapy is used in treatment of breast cancer patients, and the possible relationships between the influence of growth factors on cells and their radiation sensitivity are therefore of interest. Cell growth and radiation sensitivity of the human oestrogen and progesterone receptor positive cell line T-47D were investigated following exposure to the growth factors IGF-1, TGF-alpha and TGF-beta. Experiments were done with standard medium and in growth factor defined medium. Changes in cell cycle distribution were investigated by flow cytometry. The cell growth was significantly decreased by removal of growth factors in the culture medium, an effect which partly could be reversed by supplementation of growth factors. The growth factors decreased the cellular doubling time in standard medium, but to a smaller extent than seen in growth factor defined medium. The radiation sensitivity and plating efficiency were slightly affected by growth factor defined versus standard growth conditions. Additional growth factor exposure was able to some extent to change the radiation sensitivity, mainly by effects due to changes in repair of sublethal damage. Only minor changes were seen in phase distribution of these cells. Cellular growth was dependent on presence of different growth factors, and changes in growth factor conditions greatly influenced the cellular doubling time in vitro. Corresponding changes in radiation sensitivity were minor for doses relevant for radiation therapy.