Residual mediastinal masses in Hodgkin disease: prediction of size with MR imaging.

Abstract

Eighteen patients with mediastinal involvement of Hodgkin disease were examined with magnetic resonance (MR) imaging before and during therapy to find out if size of residual masses could be predicted from the MR characteristics of the tumor at diagnosis. After the first treatment, a significant decrease in T2 values and signal intensity ratios of tumor to fat and tumor to muscle was found in all patients. There was no significant change in T1 values. The relative decrease in tumor size correlated well with signal intensity ratios and poorly with T2 values of the original tumor. No correlation with T1 values was found. The authors conclude that size of the residual mass can be predicted from the initial size of the tumor and the signal intensity ratios at diagnosis. Since the degree of low signal intensity in the tumor before treatment probably reflects the amount of fibrotic tissue, these results support the hypothesis that residual masses after treatment are remnants of the fibrotic stroma of the original tumor.

Residual mass after treatment of primary cervical lymphoma: The utility of gallium 67 and MRI

“…This allowed the patient to be followed without additional therapy. The utility of MR imaging in differentiating fibrosis from tumor recurrence in patients with thoracic Hodgkin's lymphoma [6] and patients with gynecologic malignancy [7] has been described. Residual fibrotic mass demonstrates relatively decreased signal intensity on long TR/TE sequences when compared to muscle or subcutaneous fat, whereas residual or recurrent tumor shows increased signal intensity.…”

Thoracic positron emission tomography using18F-fluorodeoxyglucose for the evaluation of residual mediastinal Hodgkin disease

“…MRI has been reported to provide prognostic information by discriminating between active malignant tissue and fibrosis/normal tissue in T2-weighted images. [17][18][19] However, MRI has a low sensitivity and is therefore not useful for lymphoma. 20 67 Gallium scintigraphy is a metabolic imaging technique to detect active tumor tissue, but it has disadvantages such as a low spatial resolution, lack of specificity, and difficulty in quantification of uptake.…”

“…A delay in the diagnosis of progression or early relapse may result from this strategy and could mean a loss of precious time for salvage therapy. 18 F-fluorodeoxyglucose (FDG) positron emission tomography (PET) is a relatively new diagnostic method compared with CT or MRI and has been reported to detect active tumors in many cancer entities, especially in lymphomas. [7][8][9][10] There are 2 clinically relevant indications for FDG PET in patients suffering from HD.…”

Response during radiotherapy may be associated with outcome in mediastinal Hodgkin's disease

“…However, as shown by Willett et al [2], a more accurate method to assess the amount of disease within the mediastinum is to measure mediastinal volumes with serial thoracic CT scans. MRI may also emerge as a useful technique to predict the size of residual mediastinal masses in this patient population [15].…”