Negative bone scintigraphy with diffuse osteoblastic breast carcinoma metastases

Diffuse osteosclerosis in a patient with prostate cancer

A 61-year-old man was referred to our outpatient clinic because of severe bilateral upper leg pain for 1 year. On admission, the patient had anemia and a high serum alkaline phosphatase level. Lumbar and femoral neck T-scores were +10.5 and +9.6, respectively. His radius 33 % T-score was -2.8. Plain radiographs of the patient's pelvis, spine, and long bones revealed osteosclerosis. The patient had previously undergone a prostate biopsy, which showed prostate adenocarcinoma (Gleason score 3 + 4). The patient's total and free prostate-specific antigen were very high. According to previous records, the patient did not have anemia, and his serum alkaline phosphatase (ALP) level was normal. An abdominal radiograph taken 2 years earlier revealed a normal spine and pelvic bone. Bone scintigraphy yielded nontypical findings for prostate cancer metastasis. Computed tomography of the patient's thorax and abdomen showed heterogeneous sclerotic areas in all bones consistent with prostate cancer metastasis. A bone marrow biopsy disclosed disseminated carcinomatosis of bone marrow in association with prostate cancer. Clinicians should be aware of the possibility of prostate malignancy as a cause of high bone mineral density (BMD), even in the absence of typical localized findings on plain radiographs.

Human osteocalcin: a strong promoter for nitric oxide synthase gene therapy, with specificity for hormone refractory prostate cancer

BACKGROUND

Gene therapy has been identified as a promising treatment strategy for hormone refractory prostate cancer (HRPC). We report, for the first time, the use of the human osteocalcin (hOC) promoter to control inducible nitric oxide synthase (iNOS) transgene expression in HRPC.

METHODS

Human prostate carcinoma cells (PC3, DU145, LNCaP), colon cancer cells (HT29) and human microvascular endothelial cells (HMEC-1) were transfected in vitro with constitutively driven CMV/iNOS or hOC/iNOS plasmid DNA by cationic lipid vector. End points of these experiments were Western blotting, NO(.) generation using the Greiss test to measure accumulated nitrite, and clonogenic assay.

RESULTS

Transfection of the hOC/iNOS plasmid increased iNOS protein and total nitrite levels in PC3 and DU145 cells, but not LNCaP or HT29. Transfection with CMV/iNOS or hOC/iNOS resulted in no additional cytotoxicity in androgen-dependent LNCaP cells or in the non-prostate cell lines. However, transfection with either construct resulted in a greatly reduced cell survival (to 10-20%) in the androgen-independent PC3 and DU145 cell lines.

CONCLUSIONS

Utilising the tumour-type specific properties of the hOC promoter in tandem with the iNOS gene, we have demonstrated target cell specificity, and transgene activation, in the androgen-independent prostate cancer cell lines (PC3 and DU145), an effect absent in normal and androgen-dependent cells. Furthermore, the levels of NO(.) generated are comparable with those seen generated with constitutively (CMV)-driven iNOS. The data obtained from this study provide a basis for future development of hOC/iNOS gene therapy.

Alpha CTX as a Biomarker of Skeletal Invasion of Breast Cancer: Immunolocalization and the Load Dependency of Urinary Excretion

We recently showed that increased urinary excretion of the cross-linked, nonisomerized form of the C-telopeptide of collagen type I (alphaalphaCTX) could be a sensitive indicator of the presence of bone metastases in breast cancer patients. The present study was sought to investigate (a) the localization of alphaCTX epitopes in the proximity of a bone metastasis and (b) the relationship between number of metastases and the urinary excretion of alphaalphaCTX. Adjacent bone sections from breast cancer patients were stained for the presence of tumor cells (anti-cytokeratin antibody), osteoclasts (TRAcP activity), and alphaCTX (anti-alphaCTX antibody). The association between the extent of metastatic bone disease and urinary excretion of alphaalphaCTX measured with ELISA was assessed in 90 breast cancer patients (45 with bone metastasis and 45 without bone metastasis). Immunohistochemistry revealed accumulation of TRAcP-positive osteoclasts and intense staining for alphaCTX epitopes in the proximity of cytokeratin-positive bone metastasis. Areas of alphaCTX staining showed unstructured bone tissue under polarized light. In addition, there was a significant linear association between the number of bone metastases and the urinary levels of alphaalphaCTX in breast cancer patients with metastatic bone disease, independent of age and body mass index (r = 0.56, P < 0.001). The estimated relative increases in alphaalphaCTX associated with the presence of one, two, or three metastases are 38%, 57%, and 81%, respectively. Taken into account the 17% intraindividual variation of the assay, alphaalphaCTX could be a sensitive biochemical marker for the close monitoring of cancer patients aiming the facilitation of early metastasis detection.

The usefulness of 99mTc-HMPAO-labeled leukocyte scintigraphy in the diagnosis of skeletal metastases of cancers

The usefulness of bone marrow scintigraphy with 99mTc-HMPAO-labeled leukocytes (leukocyte bone marrow scintigraphy) in the diagnosis of skeletal metastases of cancers was investigated in 70 lesions in 27 patients with various types of cancer. The final diagnosis of skeletal metastases was based on one or more criteria consisting of histological confirmation, typical findings of metastases by bone radiograph, CT and MRI, or progressive swellings of the lesions with severe pain due to nerve compression. Of the 70 lesions, 55 were finally diagnosed as metastases, and 15 as benign lesions. Leukocyte bone marrow scintigraphy showed photopenic defects in 52 of the 55 metastatic lesions (sensitivity 95%), and the remaining 3 negative lesions were found positive for metastases by MRI. In contrast, MRI could evaluate only 39 of the 55 lesions because 16 lesions in the ribs, scapula and sternum were not visualized. Of these 39 lesions, MRI showed positive findings for metastases in 33 (sensitivity 85%), and negative findings in 6 with photopenic defects found by leukocyte bone marrow scintigraphy. Of the 15 benign lesions, 3 were false positive for metastases on leukocyte bone marrow scintigraphy (specificity 80%). We conclude that 99mTc-HMPAO-labeled leukocyte bone marrow scintigraphy may be useful in the diagnosis of skeletal metastases of cancers, particularly when MRI fails to evaluate the lesions.

Early detection and accurate description of extent of metastatic bone disease in breast cancer with fluoride ion and positron emission tomography

PURPOSE

Previous studies have shown that bone metastases are revealed by magnetic resonance imaging (MRI) or bone marrow scintigraphy several months before they are visible by conventional bone scintigraphy (BS). We present a new approach for detecting bone metastases in patients with breast cancer. We compared findings obtained with fluoride ion (F-18) and positron emission tomography (PET) with those obtained with conventional BS.

PATIENTS AND METHODS

Thirty-four breast cancer patients were prospectively examined using F-18-PET and conventional BS. F-18-PET and BS were performed within 3 weeks of each other. Metastatic bone disease was previously known to be present in six patients and was suspected (bone pain or increasing levels of tumor markers, Ca(2+), alkaline phosphatase) in 28 patients. Both imaging modalities were compared by patient-by-patient analysis and lesion-by-lesion analysis, using a five-point scale for receiver operating characteristic (ROC) curve analysis. A panel of reference methods was used, including MRI (28 patients), planar x-ray (17 patients), and spiral computed tomography (four patients).

RESULTS

With F-18-PET, 64 bone metastases were detected in 17 patients. Only 29 metastases were detected in 11 patients with BS. As a result of F-18-PET imaging, clinical management was changed in four patients (11.7%). For F-18-PET, the area under the ROC curve was 0.99 on a lesion basis (for BS, it was 0.74; P <.05) and 1.00 on a patient basis (for BS, it was 0.82; P <.05).

CONCLUSION

F-18-PET demonstrates a very early bone reaction when small bone marrow metastases are present, allowing accurate detection of breast cancer bone metastases. This accurate detection has a significant effect on clinical management, compared with the effect on management brought about by detection with conventional BS.

Total-body echo-planar MR imaging in the staging of breast cancer: comparison with conventional methods--early experience

PURPOSE

To test breast cancer staging with total-body echo-planar magnetic resonance (MR) imaging.

MATERIALS AND METHODS

Nineteen patients with newly diagnosed breast cancer were imaged by using a 1.5-T echo-planar MR system. By using a table sweep method, 180 contiguous axial images were obtained from the cranial vertex through the feet with T2-weighted spin-echo and inversion-recovery sequences. Results were compared with those of conventional imaging. Therapeutic decisions based on echo-planar MR imaging and conventional imaging results were compared. Diagnostic truth was determined by means of tissue diagnosis, further imaging findings, and follow-up findings (median, 18 months).

RESULTS

Staging with total-body echo-planar MR imaging was correct in 18 patients (95%)--eight with metastases and 10 without--while staging with conventional imaging was correct in 15 patients (79%). In one patient, both echo-planar MR imaging and conventional imaging findings incorrectly indicated probable metastases. In one patient thought to have bone metastases at conventional imaging, echo-planar MR imaging findings were normal, which was correct. Two patients with stage IV disease were not suspected to have disease at conventional imaging: One had liver involvement and the other had skeletal metastases. The therapeutic decisions in these two patients were altered by the echo-planar MR imaging results.

CONCLUSION

Total-body echo-planar MR imaging was at least as accurate as conventional imaging for staging newly diagnosed breast cancer and was faster, simpler, and completely noninvasive.

A musculoskeletal radiologist's view of nuclear medicine

The introduction of cross-sectional and multiplanar imaging techniques has not diminished the value of radionuclide bone scanning. Skeletal scintigraphy remains an extremely effective and relatively inexpensive tool for diagnosis of many disorders of bones and joints. The sensitivity of scintigraphy in detecting stress fractures approaches 100%, although it is less specific than plain film radiography. However, radionuclide bone scanning can reveal subtle early changes in bone metabolism. For evaluation of infections, particularly in patients with diabetic foot neuropathy, scintigraphy is the modality of choice, although a combination of imaging techniques may be necessary in previously damaged bone. Radionuclide bone scanning has retained its place in the evaluation of primary bone tumors and metastases, and in screening of patients with metabolic bone disease. The radiologist should be aware that although this modality is generally used as an ancillary technique in conjunction with plain radiography, conventional tomography, computed tomography (CT), and magnetic resonance imaging (MRI), at times it can be used as the primary modality not only for the identification of skeletal lesions but also to provide important information required to make a definite diagnosis.

Is it cancer or not?

Two cases are reviewed in whom a positive bone scan led to a diagnosis of metastatic bone disease and hospice referral. One of these was subsequently shown on magnetic resonance image (MRI) scanning to have benign metabolic bone disease; in the other, a repeat bone scan 18 months later confirmed benign pathology. The potential impact on patient and family in these situations is considerable and the usefulness of MRI in distinguishing benign from malignant bone disease is discussed.

Diagnostic bone scanning in oncology

Over the last several decades bone scanning has been used extensively in the evaluation of oncology patients to detect bone involvement. It can provide information about disease location, prognosis, and the effect of therapy. Bone scanning offers the advantages of whole body evaluation and the detection of lesions earlier than other techniques. However, as newer diagnostic tools become available, indications for bone scanning must be revised and the results combined with these other tests in order to provide optimum patient care. Advances in instrumentation and the subsequent improvement in image quality have allowed nuclear medicine physicians to provide more accurate bone scan interpretations. By optimizing image acquisition, it is often possible to determine lesion characteristics, which are more likely to represent malignancy. Knowledge of disease pathophysiology and other specific properties of the patient's primary tumor, along with subsequent correlation of scan abnormalities to patient history, physical examination, previous studies, and other radiological examinations, is essential for determining lesion significance. The differential diagnosis of a scan abnormality should also include consideration of both false normal and abnormal causes. The final interpretation should be clearly communicated to the clinician with appropriate recommendations for further evaluation. Only through careful attention to the patient, the clinician, and appropriate study acquisition parameters will bone scanning maintain its place in the evaluation of oncology patients.

Incidental detection of skeletal metastases on technetium-99m DTPA renal scintigraphy

A case is presented where skeletal metastases from a prostate carcinoma were detected during 99mTc DTPA scintigraphy performed for evaluation of renal function. The lumbar vertebrae in camera field of view were intensely perfused on the arterial phase of the radionuclide flow study. Tracer pooling in these vertebrae, visualized on initial serial images, progressively faded over the 30 minute study. Widespread areas of increased radionuclide uptake, consistent with skeletal metastases, were detected on 99mTc MDP bone imaging performed two days later. Subsequent prostatic biopsy revealed a well differentiated primary adenocarcinoma.