Bone-marrow MR imaging before and after autologous marrow transplantation in lymphoma patients without known bone-marrow involvement.

PURPOSE: To study lumbar bone marrow by means of MR imaging before and after bone-marrow transplantation in lymphoma patients. Particular emphasis was paid to heterogeneity and to focal manifestations, i.e. appearances that could simulate tumor. MATERIAL AND METHODS: Twenty-two patients who were disease-free for a minimum of 30 months after transplantation were studied in 107 MR examinations. Two radiologists visually evaluated coronal T1-weighted and short inversion time inversion-recovery (STIR) images. RESULTS: T1-weighted images demonstrated a more heterogeneous marrow after transplantation than before it. Sharply defined focal low signal intensity areas appeared on this sequence in 5 (23%) of the 22 patients at between 21 and 60 weeks after transplantation. The mean age of these 5 patients was 48.4 years (range 42-54 years). The difference in age between these 5 patients and the remaining 17 patients, who had a mean age of 33.4 years (range 14-51 years), was statistically significant (p < 0.01, Student's t-test, 2-sided test). CONCLUSION: Sharply defined focal low signal intensity areas may be seen on T1-weighted images of bone marrow in patients who are in complete remission after transplantation, particularly in those aged over 40-45 years.

Critical soft tissues of the female pelvis: serial MR imaging before, during, and after radiation therapy.

PURPOSE: To evaluate the findings in the irradiated critical soft-tissue organs of the female pelvis at magnetic resonance (MR) imaging within 30 months after radiation therapy. MATERIALS AND METHODS: Twenty-three patients (13 premenopausal and 10 postmenopausal women) with advanced cervical carcinoma underwent 276 MR examinations (T1- and T2-weighted imaging) scheduled before, three times during, and 7 weeks and 3, 6, 9, 12, 18, 24, and 30 months after the end of radiation therapy. A visual evaluation of the ureters, bladder, rectum, parametrium, and perivesical and perirectal soft tissues was performed by two radiologists. RESULTS: Fifteen abnormally wide ureters (diameter range, 7-23 mm; mean diameter, 14 mm) were seen in 10 (seven premenopausal and three postmenopausal women) (43%) of 23 patients at a median time of 18 months after the end of radiation therapy (range, 9-30 months). An abnormally wide ureter was a transient finding in eight (53%) of 15 abnormal ureters. Two premenopausal women (9%) of 23 patients had rectovaginal fistulas. One of these two patients also had a vesicovaginal fistula. CONCLUSION: Ureteral dilatation was seen in nearly half of the patients and occurred more frequently in premenopausal women than in postmenopausal women. Knowledge about the appearances of radiation-induced abnormalities of the critical soft tissues may be of help in the interpretation of MR images of the pelvis.

Incidence of radiation-induced insufficiency fractures of the female pelvis: evaluation with MR imaging.

OBJECTIVE: The purpose of this study was to assess the incidence, time of appearance, and evolution of radiation-induced insufficiency fractures of the female pelvis with MR imaging. SUBJECTS AND METHODS: Eighteen women (nine premenopausal and nine postmenopausal) with advanced cervical carcinoma were studied prospectively with MR imaging. The examinations totaled 216 and were scheduled before radiation therapy, three times during radiation therapy, and eight times after radiation therapy. T1-weighted and short inversion time inversion recovery images were obtained. The images were evaluated by two radiologists in consensus. The criterion for fracture was edema, indicated by an area of high signal intensity on short inversion time inversion recovery images and corresponding low signal intensity on T1-weighted images. CT scans (n = 61) and bone scans (n = 58) were used to confirm each diagnosis of fracture. RESULTS: Sixteen (89%) of 18 patients (seven premenopausal and nine postmenopausal) showed findings compatible with insufficiency fractures. Thirteen patients had more than one lesion. The first fracture was detected between 3 and 12 months after the end of radiation therapy. During the study, the fractures associated with edema subsided without treatment in 41 (79%) of 52 lesions in 15 (94%) of 16 patients. Fractures were confirmed with additional imaging in all 16 patients (CT in 14 patients and bone scanning in nine patients). CONCLUSION: Radiation-induced insufficiency fractures were frequently seen in premenopausal and postmenopausal women within 12 months after radiation therapy. Multiple fractures developed within 24 months. Twenty-one percent of the lesions healed during the observation period of 30 months.

Noncritical soft tissues of the female pelvis: serial MR imaging before, during, and after radiation therapy.

PURPOSE: To present the findings of the irradiated noncritical soft tissues of the female pelvis at magnetic resonance (MR) imaging within 18 months after radiation therapy (RT). MATERIALS AND METHODS: The soft tissues of the pelvis of 24 women with advanced cervical carcinoma were studied in 240 MR examinations scheduled before, three times during, and 7 weeks and 3, 6, 9, 12 and 18 months after RT. Two radiologists visually evaluated the signal intensity (SI) of the subcutaneous fat, muscles, and presacral space (PS) on T1- and T2-weighted and short inversion time inversion-recovery images. RESULTS: SI compatible with edema appeared in the PS, pelvic muscles, and subcutaneous fat within 3 months after the end of RT and was observed in 23 (96%) of the 24 patients. During the observation period, the edema subsided. Eighteen months after treatment, edema in the PS was seen in 12 (50%) of the 24 patients. CONCLUSION: The soft tissues of the female pelvis showed a characteristic pattern of varying edema after irradiation.

Female pelvic bone marrow: serial MR imaging before, during, and after radiation therapy.

PURPOSE: To study early changes in irradiated pelvic and adjacent nonirradiated bone marrow with T1-weighted magnetic resonance (MR) and short inversion time inversion-recovery (STIR) imaging. MATERIALS AND METHODS: The bone marrow of 31 women with advanced cervical carcinoma was studied in 161 MR examinations before, during, and 7 weeks after radiation therapy. Two radiologists visually evaluated the marrow signal intensity (MSI) on T1-weighted and STIR images. RESULTS: Changes in irradiated and adjacent nonirradiated marrow were shown on T1-weighted images in 31 (100%) and 18 (58%) of the 31 patients, respectively. MSI changes on images were observed as early as 8 days after the start of radiation therapy and occurred more frequently in irradiated than in adjacent nonirradiated marrow. In the irradiated regions, a complete fatty marrow was seen on T1-weighted images obtained 6-8 weeks after the start of radiation therapy in 28 (90%) of the 31 patients. CONCLUSION: T1-weighted and STIR images obtained during and soon after radiation therapy complement each other in showing changes in bone marrow.

Radiation-induced insufficiency fractures of the sacrum: evaluation with MR imaging.

In patients with malignant pelvic tumors, radiation-induced insufficiency fractures of the sacrum may be mistaken for metastasis. Magnetic resonance (MR) imaging was performed in 18 patients with this condition, and the findings were studied retrospectively. The diagnosis was confirmed with at least one additional imaging modality in 16 patients, whereas the other two patients underwent clinical follow-up at 13 and 20 months without evidence of metastasis. In 17 patients, the lesions were consistent with edema and had diffuse low signal intensity on T1-weighted images and diffuse high signal intensity on short-inversion-time inversion-recovery images, thereby simulating metastasis. In one patient, bilateral sacral wing fractures were demonstrated directly as fairly well-defined linear zones. The alae sacri were involved in all patients; 16 patients had bilateral lesions. Awareness of this clinical entity and of the high sensitivity of MR imaging for demonstrating edema caused by the fracture should prevent confusion with metastatic disease and inappropriate treatment.

Clinical stage I carcinoma of the cervix. Value of MR imaging in determining invasion into the parametrium.

Using MR imaging with a body coil parametrial invasion was determined prospectively in 169 consecutive patients considered on the basis of clinical examination to have carcinoma confined to the cervix. After radical hysterectomy correlation with histologic examination was performed for the left and right parametrium separately. The criterion for parametrial invasion was a high-signal-intensity lesion with disruption of the full thickness of the cervical stroma combined with areas of abnormal signal intensity within the parametrial region on T2-weighted images. Histologic examination showed that 18 parametria in 13 patients were invaded by tumor. MR had an overall accuracy of 93%, a sensitivity of 89%, and a specificity of 93% in demonstrating parametrial involvement. Positive and negative predictive values were 43% and 99%. The main weakness of MR was 21 false-positive tests. This represents a limitation when MR is performed with a body coil.

Cancer of the endometrium: value of MR imaging in determining depth of invasion into the myometrium.

The depth of invasion into the myometrium correlates with the frequency of lymph node metastases in patients with cancer of the endometrium. A distinction between superficial invasion (less than 50% of the thickness of the myometrium) and deep invasion (greater than 50%) is particularly important. The ability to distinguish between these two groups on MR was studied in 33 patients with endometrial cancer who had primary hysterectomy. The overall accuracy of MR in showing deep invasion was 82%, with a sensitivity of 91% and a specificity of 64%. The main limitation of MR was four false-positive results with regard to deep invasion. In all of these, the erroneous diagnosis was found at histologic examination to be due to a large polypoid tumor that distended the uterus so that a thin rim of myometrium was stretched over it rather than being deeply infiltrated by it. Our experience shows that MR can be used to distinguish between superficial and deep invasion of the myometrium. However, degree of invasiveness may be overestimated in exophytic polypoid tumors with significant intraluminal extension.

Clinical stage I carcinoma of the cervix: value of MR imaging in determining degree of invasiveness.

The depth of tumor invasion measured at histologic examination is the most important prognostic factor in early-stage carcinoma of the uterine cervix. The ability of MR to estimate the depth of tumor invasion was studied in 47 patients who subsequently underwent radical hysterectomy. In two patients, MR failed to detect tumors with infiltration depths of 2 and 4 mm. The maximum sagittal tumor length along the axis of the cervix (D) and the maximum tumor area on sagittal (S) and axial (A) images were measured with MR. The depth of tumor infiltration determined histologically (I) correlated with the degree of infiltration noted on MR images. The univariate correlation coefficients for log I vs log D, log S, and log A were .87, .84, and .77, respectively. By stepwise inclusion of the variables in a multivariate analysis, the contributions to the coefficient of determination from including log S and log A after log D were less than 1%. The regression analysis showed that the best estimate for the depth of invasion was close to half of the sagittal tumor length measured on MR, I = D/2. Our experience shows that MR is valuable in determining the degree of invasiveness in clinical stage I tumors.

Osteogenic sarcoma: MR signal abnormalities of the brain in asymptomatic patients treated with high-dose methotrexate.

The advent of lesions with high signal intensity in periventricular white matter was incidentally observed on T2-weighted images in one patient who underwent magnetic resonance (MR) imaging of the brain after administration of high-dose methotrexate (HDMTX) for osteogenic sarcoma. Twenty-one additional symptom-free patients who had been treated with the same regimen and 10 patients who had undergone cisplatin-based chemotherapy for testicular cancer also underwent examination. Fourteen of the patients with osteosarcoma showed high-signal-intensity lesions in white matter on T2-weighted images. The interval between the last course of chemotherapy and MR imaging was a factor in this finding, as 12 of 14 patients who underwent examination within 2 years after chemotherapy had a positive finding, as opposed to two of eight patients who underwent examination later. The patients with testicular cancer had normal MR images. The occurrence of MR imaging abnormalities in asymptomatic patients treated with HDMTX for osteogenic sarcoma may be subclinical evidence of treatment-related central nervous system toxicity.

CT in primary malignant germ cell tumors of the retroperitoneum.

Malignant germ cell tumors may exist as a primary entity in the retroperitoneum. In a CT study of 14 males with this condition (2 seminomas and 12 non-seminomatous tumors) all masses were large, lobulated and of mixed density. Fat plane obliteration against adjacent structures was frequent. The aorta was embedded in 9 patients and the inferior vena cava was affected in 7, 2 of whom had signs of compromised caval blood flow. Distant metastases were found in the lungs (7 patients), liver (n=4), posterior mediastinum (n=3), and in brain and supraclavicular lymph nodes in one patient each. Serum biomarkers were elevated in 11 patients. An extragonadal germ cell tumor should be considered when CT of the abdomen reveals a large retroperitoneal mass with mixed density.

Magnetic resonance imaging of malignant extradural tumors with acute spinal cord compression.

Thirty-six cancer patients with extradural spinal metastatic disease and acute symptoms of spinal cord compression underwent magnetic resonance (MR) imaging at 1.5 T. Cord involvement was found in all 36, 7 of whom had lesions at 2 different sites. Vertebral metastases in addition to those corresponding to the cord compressions were detected in 27 patients, and 18 of these had widespread deposits. MR displayed the extent of the tumors in the craniocaudal and lateral directions. The ability to identify multiple sites of cord and vertebral involvement and to delineate tumor accurately makes MR the examination of choice in cancer patients with suspected spinal cord compression. It obviates the need for myelography and postmyelography CT in this group of patients.

Management of patients with poor-prognosis nonseminomatous germ cell cancer.

The treatment and outcome of 57 patients with poor-prognosis metastatic nonseminomatous germ cell cancer were reviewed. The patients were treated between 1980 and 1986. Poor-prognosis patients were characterized by the presence of at least one of the following findings: (1) retroperitoneal tumor mass greater than 10 cm; (2) greater than 3 lung metastases, the largest being greater than 2 cm; (3) extrapulmonary, extralymphatic, metastases; and (4) extragonadal primary tumor. The intended treatment consisted of cisplatin-based combination chemotherapy followed by secondary surgery. From 1980 to 1983 a modified Einhorn regimen was used (cisplatin 100 mg/m2 per cycle; CVB). In case of unacceptable vinblastine toxicity, this drug was substituted by VP-16 (500 mg per m2 per cycle; BEP20). From October 1983 the intention was to replace at least 3 of the CVB/BEP20 cycles by BEP60 cycles (days 1-3: cisplatin 60 mg/m2, days 1-3: VP-16 120 mg/m2; days 1, 5, 15: bleomycin 30 mg). There were 33 patients in the CVB/BEP20 group and 24 patients in the BEP60 group. Two patients of the CVB/BEP20 group and 6 patients of the BEP60 group were not evaluable for response, but are included in the survival analysis. The reasons for exclusion from response evaluation were that these patients could not receive the intended chemotherapy in appropriate doses due to severely reduced pretreatment general condition or due to early death. Fourteen patients with multiple lung metastases but no other poor-prognosis criteria had a 93% survival indicating that they did not represent poor-prognosis germ cell cancer. After excluding these 14 patients, the 4-year survival was 58% for 19 CVB/BEP20 patients and 72% for BEP60 patients. This difference did not reach the level of statistical significance in this limited series. The introduction of high-dose cisplatin had thus not led to clearly superior treatment results as compared to CVB/BEP20.

Computed tomography in primary non-seminomatous germ cell tumors of the mediastinum.

Germ cell tumor exists as a primary entity in the anterior mediastinum. In a CT study of two males and one female with primary non-seminomatous germ cell tumors all masses were large and lobulated with a mixed density. The fat planes were for the most part obliterated. A high attenuating border was present around parts of the tumor in all three cases, and the pleura-lung interfaces were irregular. One patient had pericardial and left pleural effusions as well as tumor invasion of the anterior chest wall. An extragonadal germ cell tumor should be considered when CT of the thorax reveals a large mass in the anterior mediastinum of a young adult.