Cancer Treatment

Cardiac CT

Over the past decade, electron beam computed tomography (CT) and multidetector CT have increasingly been used to identify and measure coronary artery calcification. Calcification levels can be related to the extent and severity of underlying atherosclerosis and can potentially improve cardiovascular risk prediction. However, broad use of these methods for screening is controversial. The American Heart Association (AHA) has released guidelines for the use of cardiac CT when evaluating patients for coronary artery disease (Table 1).

Asymptomatic patients at low or high risk of cardiovascular disease do not benefit from coronary calcium measurements. However, these measurements may benefit asymptomatic, intermediate-risk patients by refining the risk assessment and prompting lifestyle changes and pharmacologic therapy. Coronary calcium measurements may be reasonable in some symptomatic patients, especially to determine the etiology of cardiomyopathy, to assess patients who have equivocal treadmill or functional test results, and to assess patients with chest pain who have equivocal or normal echocardiography findings and negative cardiac enzyme test results.

http://radiology.rsnajnls.org/cgi/reprint/235/3/723.pdf

Amber Huntzinger AHA guidelines on cardiac CT for assessing coronary artery disease
American Family Physician,  March 1, 2008 

Imaging for osteoporosis

Three major imaging modalities are commonly used in the clinical setting: DXA, quantitative computed tomography (QCT), and calcaneal ultrasonography. DXA is the msot commonly used. QCT measures the lumbar spine as well as peripheral sites (Figure 3). The results are less likely to be affected by degenerative spinal changes than PA spine DXA scanning. Also, unlike DXA, QCT allows for selective assessment of both cortical and trabecular bone. Trabecular bone, because of its higher rate of turnover compared with cortical bone, would be expected to show metabolic changes earlier. Its ability to enable prediction of spinal fracture, however, is equal to that of DXA scanning; the cost and level of radiation exposure are higher.

Deciding which bone imaging modality to use is not always easy.Vertebral fractures are of much greater concern than hip fractures in women who are younger than 65 years of age or within 15 years of menopause. Any of the imaging modalities may be appropriate, especially those that include imaging of the spine. In women older than 65 years, hip fractures become more of a concern, and degenerative spinal changesand aortic calcification,25 are more prevalent. Thus, in this population, hip imaging, lateral spine DXA, and peripheral imaging (e.g., calcaneal ultrasonography) may be suitable alternatives. PA spinal DXA should be avoided.

QCT measures the lumbar spine as well as peripheral sites. The results are less likely to be affected by degenerative spinal changes than PA spine DXA scanning. Also, unlike DXA, QCT allows for selective assessment of both cortical and trabecular bone. Trabecular bone, because of its higher rate of turnover compared with cortical bone, would be expected to show metabolic changes earlier.

1. Genant HK, Engelke K, Fuerst T, Gluer CC, Grampp S, Harris ST, et al. Noninvasive assessment of bone mineral and structure: state of the art. J Bone Miner Res 1996;11:707-30.
2. Greenspan SL, Maitland-Ramsey L, Myers E. Classification of osteoporosis in the elderly is dependent on site-specific analysis. Calcif Tissue Int 1996;58: 409-14.
3. 30. Cheng S, Tylavsky F, Carbone L. Utility of ultrasound to assess risk of fracture. J Am Geriatr Soc 1997;45:1382-94.
4. Baran DT, Faulkner KG, Genant HK, Miller PD, Pacifici R. Diagnosis and management of osteoporosis: guidelines for the utilization of bone densitometry. Calcif Tissue Int 1997;61:433-40.
5. Patel R, Blake GM, Rymer J, Fogelman I. Long-term precision of DXA scanning assessed over seven years in forty postmenopausal women. Osteoporos Int 2000;11:68-75.
6. Richmond BJ, Dalinka MK, Daffner RH, Bennett DL, JA Jacobson, Resnik CS, Roberts CC, Rubin DA, Schweitzer ME, Seeger LL, Taljanovik M, Weissman BN, Haralson RH, Expert Panel on Musculoskeletal Imaging. Osteoporosis and bone mineral density. [online publication]. Reston (VA): American College of Radiology (ACR); 2007. 12 p. [62 references]

IN-111 octreotide to treat carcinoid

GThe most important treatment modality for the carcinoid syndrome (flushing, diarrhea etc) due  to carcinoid secreted hormones)  is octreotide, a synthetic hormone similar in structure to the naturally-occurring hormone, somatostatin. Octreotide, like somatostatin, binds to receptors on the cells of carcinoid tumors and inhibits the manufacture and release of tumor hormones. Octreotide is very effective in controlling the symptoms of flushing and diarrhea that are part of the carcinoid syndrome. Octreotide has been found to reduce the excretion of 5-HIAA in some patients. Octreotide also has been found to slow the growth of carcinoid tumors, and, in a few patients, even reduce the size of the tumors and their metastases. Treatment with octreotide prior to surgery is important in order to prevent life-threatening carcinoid crisis in patients with carcinoid syndrome undergoing surgery.

Octreotide generally is well tolerated. Side effects include nausea, headache, dizziness, abdominal pain, diarrhea, elevated blood sugar levels, and gallstones. The major drawback of octreotide is the need to inject it under the skin three times daily. Other longer-acting synthetic hormones resembling somatostatin (for example, lanreotide) can be given intramuscularly every two weeks, but they are not yet available in the U. 

This patient received this therapy but what is being proposed is high-dose IN-111 octreotide as therapy.
There are a number of cse reports of this modlaity that suggest effectiveness and tumor regression; however, there have been no randomized studies and it remains an unproven treatment. In addition, this patient appears to be enrolled into a clincail study of this treatment.

S.. A. Kaltsas, G. M. Besser, and A. B. Grossman
The Diagnosis and Medical Management of Advanced Neuroendocrine Tumors
Endocr. Rev., June 1, 2004; 25(3): 458 - 511.

P. L. Filosso, E. Ruffini, A. Oliaro, E. Papalia, G. Donati, and O. Rena
Long-term survival of atypical bronchial carcinoids with liver metastases, treated with octreotide
Eur. J. Cardiothorac. Surg., May 1, 2002; 21(5): 913 - 917.

nccn.org, carcinoid

Buscombe, J. R.; Caplin, M. E.; Hilson, A. J.W Treating disseminated NETs with high activity In-111 Octreotide.  Nuclear Medicine Communications. 21(6):567, June 2000.

http://www.liebertonline.com/doi/pdf/10.1089/cbr.2005.20.215?cookieSet=1

MRI for Ovarian Cancer

Lay Summary: MRI should be reserved for problem solving when CT is not conclusive.

RI is an excellent problem-solving technique by virtue of its ability to define common conditions such as fibroids, dermoid cysts, endometriomas, and other benign lesions. Two studies found no statistical difference between CT and MRI in defining disease extent. A multivariate analysis showed that the accuracy of MRI with gadolinium enhancement in diagnosing ovarian malignancy was 93%. Gadolinium enhancement improved diagnostic confidence and tissue characterization. However, the role of MRI has been limited because the use of intraluminal gastrointestinal contrast agents with MRI is not routine as it is with CT, MRI generally costs more than CT, and there are fewer experienced radiologists to interpret MRI. Thus, CT is currently the recommended modality to stage ovarian cancer. MRI is recommended for patients with a contraindication to the use of iodinated contrast agents (allergy, renal insufficiency), patients who are pregnant, and those for whom CT findings are inconclusive.

A recent guideline rates MRI as 8 : "Evidence shows equivalent staging accuracy compared to CT. Problem solving modality for patients who cannot have contrast enhanced CT. "

Javitt MC, Fleischer AC, Andreotti RF, Angtuaco TL, Horrow MM, Lee SI, Lev-Toaff AS, Scoutt LM, Zelop C, Expert Panel on Women's Imaging. Staging and follow-up of ovarian cancer. [online publication]. Reston (VA): American College of Radiology (ACR); 2007. 5 p. [38 references]

Sohaib, SA, Mills, TD, Sahdev, A, Webb, JA, Vantrappen, PO, Jacobs, IJ and Reznek, RH. (2005) The role of magnetic resonance imaging and ultrasound in patients with adnexal masses. Clin Radiol 60: 340-8

PET for renal cell carcinoma

In regard to PET/CT, little reliable information exists. There is currently limited experience with FDG-PET and renal cell carcinoma. One of the first studies evaluating 29 patients with solid renal masses demonstrated a sensitivity of 77% (20 of 26 patients with renal cancer)and 3 false positives (angiomyolipoma, pericytoma and pheochromocytoma). In another 3 patients, FDG-PET detected regional nodal metastases.
A second study  evaluating factors in the degree of FDG uptake in renal cell carcinoma (n = 11) demonstrated that patients with higher grade tumors had positive FDG-PET studies. The fact that many renal cell carcinomas are lower in grade may explain the relatively low sensitivity.

Another limitation with FDG-PET evaluation of renal cell carcinoma is the fact that FDG is excreted by the kidneys. Thus, variable degrees of increased uptake are normally seen in the renal parenchyma and collecting system, making detection of focal increased uptake in a tumor difficult. In this particular case, evaluation was simplified by the exophytic nature of the mass. PET scanning has been shown to be potentially useful in differentiating benign from malignant hepatic lesions, but limitations include false-positive and false-negative results.  Its sensitivity for detecting metastatic lesions is better than for determining the presence of cancer in the renal primary site.

Delbeke D, Martin WH, Sandler MP, Chapman WC, Wright JK Jr, Pinson CW. Evaluation of benign vs malignant hepatic lesions with positron emission tomography. Arch Surg. 1998;133:510-515.

Motzer RJ, Hutson TE, Tomczak P, et al. Sunitinib versus interferon alfa in metastatic renal-cell carcinoma. N Engl J Med. 2007;356(2):115-124.

Dilhuydy MS, Durieux A, Pariente A, de Clermont H, Pasticier G, Monteil J, Ravaud A.. PET scans for decision-making in metastatic renal cell carcinoma: a single-institution evaluation.Oncology. 2006;70(5):339-44

Ak I, Can C..F-18 FDG PET in detecting renal cell carcinoma.Acta Radiol. 2005 Dec;46(8):895-9

How long to PET after remission of lymphoma

Although CT remains the gold standard for the staging and follow-up of malignant lymphomas, 18F-FDG PET has a potential role in accurately staging disease and in predicting response to therapy. This role has the potential to affect both the initial choice of chemotherapy and the decision to alter management based on the initial response to therapy . PET performed early in a chemotherapeutic regimen has demonstrated a role in identifying patients who will experience relapse and may require further treatment, but attention to the timing of the scan in relation to chemotherapy and growth factors is crucial.

In regard to followup, a recent study showed that a negative PET scan after completion of therapy does not exclude the presence of residual microscopic disease and does not indicate complete remission. The majority of studies evaluating FDG-PET in lymphoma include patients with diffuse large B-cell non-Hodgkin’s lymphoma (NHL) or Hodgkin’s disease. There are limited data available on the role of PET in other histologies.

A negative PET scan at the end of therapy appears to provide favorable prognostic information. Persistently positive PET scans at the end of therapy, or in follow-up, warrant close follow-up or additional diagnostic procedures, since some of those patients may remain in prolonged remission.

The Imaging Subcommittee of the International Harmonization Project (IHP) in Lymphoma developed guidelines for performing and interpreting positron emission tomography (PET) for treatment assessment in patients with lymphoma. The new recommendations, targeting both clinical practice and clinical trials, are published in the January 22 Early Release issue of the 2007 al of Clinical Oncology. They are based on experts' consensus and not randomized evidence.

Specific recommendations related to followup are:

After treatment completion, PET should be performed at least 3 weeks, and preferably 6 to 8 weeks, after chemotherapy or chemoimmunotherapy, and 8 to 12 weeks after radiation or chemoradiotherapy. Noncontrast PET/CT can be used instead of contrast-enhanced diagnostic CT to follow-up patients with lymphoma, although patients with hepatic or splenic involvement should continue to receive contrast-enhanced diagnostic CT. Attenuation-corrected PET is much preferred over nonattenuation-corrected scans.

In regard to this case, I consider the PET to be medically necessary ONCE. This is because PET after the initial post-therapy PET is not recommended by NCCN, is not recommended specifically for T-cell histology and the duration of PET followup after remission is not well defined in guidelines.

Freudenberg LS, Antoch G, Schutt P, et al. FDG-PET/CT in re-staging of patients with lymphoma. Eur J Nucl Med Mol Imaging. 2004;31:325–329

Yuliya S. Jhanwar and David J. Straus The Role of PET in Lymphoma Journal of Nuclear Medicine Vol. 47 No. 8 1326-1334, 2006

Lavely WC, Delbeke D, Greer JP, Morgan DS, Byrne DW, Price RR, Hallahan DE, G PET in the follow-up management of patients with newly diagnosed Hodgkin and non-Hodgkin lymphoma after first-line chemotherapy.Int J Radiat Oncol Biol Phys. 2003 Oct 1;57(2):307-15.

Jonathan W. Friedberg, Vaseem ChengaziPET Scans in the Staging of Lymphoma: Current Status The Oncologist, Vol. 8, No. 5, 438–447, October 2003

J. W. Fletcher, B. Djulbegovic, H. P. Soares, B. A. Siegel, V. J. Lowe, G. H. Lyman, R. E. Coleman, R. Wahl, J. C. Paschold, N. Avril, et al.
Recommendations on the Use of 18F-FDG PET in Oncology
J. Nucl. Med., March 1, 2008; 49(3): 480 - 508.

Thermography for breast cancer detection

Thermography, when used in a clinical setting, is a diagnostic imaging procedure that detects, records, and produces an image (thermogram) of a patient's skin surface temperatures and/or thermal patterns. The procedure uses equipment that can provide both qualitative and quantitative representations of these temperature patterns.

Standardized interpretation guidelines in thermal breast imaging have been utilized since the adoption of the 20 point TH interpretation and classification system in the early 1980’s. This system has been continually updated as ongoing research has dictated. Many large-scale studies performed over the last three decades, encompassing well over 300,000 women participants, confirm the objectivity and accuracy of this interpretation and classification system. This system of interpretation is the most up-to-date method for use in the qualitative and quantitative analysis of thermal breast images. The 20 point TH interpretation and classification system is the accepted standard in thermal breast imaging analysis.

Thermography has been proposed as an alternative method of breast cancer screening. Currently, the gold standard for breast cancer screening is mammography; therefore, sensitivities, specificities, and positive and negative predictive values of thermography need to be compared against those of mammography in order to evaluate whether or not thermography is equivalent or superior to mammography. There are no published studies in the peer-reviewed scientific literature comparing the two screening techniques. Furthermore, there are no national published evidence-based practice guidelines which endorse thermography as the appropriate method of screening for early detection of breast cancer.

Thermography has been approved for this purpose for many years by the US FDA (United States Food and Drug Administration). Breast thermography is very accurate, but only in the hands of trained personnel using the correct type of thermography cameras. The accuracy of the examination varies around the world but varies from 87%-96% depending on old the literature is. Over 800 peer-reviewed studies on breast thermography exist in the index medicus literature.  In this database, well over 300,000 women have been included as study participants.  The numbers of participants in many studies are very large (10,000, 37,000, 60,000, 85,000, etc.)  Some of these studies have followed patients for up to 12 years.  These studies, however, were not definitive and many were poorly designed and hard to interpret. They showed, using mammography as the gold-standard comparison, that thermography was very sensitive but had many false positives.

Unfortunately, early enthisiasm let to widepread adoption of thermography not only in breast cancer deteection but also by chropractics and non-allopathic practitioners. Many did not have the appropriate training or experience. Farther study of this new technique diminshed in the late 1980's.

Moskowitz M. Thermography as a risk indicator of breast cancer. Results of a study and a review of the recent literature. Journal of Reproductive
Medicine 1985;30(6)):451-459.

BC guidelines -  BC Cancer Agency (http://www.bccancer.bc.ca).

http://www.nzbcf.org.nz/education/position_statements.asp

International Agency for Research on Cancer (IARC). Breast Cancer Screening. 1st ed. Lyon, France: IARC Press, 2002.

Royal Australian and New Zealand College of Radiologists Breast Imaging Reference Group policy on the use of thermography to detect breast
cancer 2001. http://www.ranzcr.edu.au/open/policies/diagnostic_imaging/pol7_3.htm

American Medical Association thermography update H-175.988: AMA Policy Finder undated.
http://www.ama-assn.org/apps/pf_new/pf_online?f_n=browse&doc=policyfiles/HnE/H-175.988.HTM

Compute Aided Detection (CAD) for MRI

Lay Summary: CAD is still investigational for breast MRI.

The use of computer-aided detection (CAD) is proposed to supplement radiologists' interpretation of contrast-enhanced magnetic resonance imaging (MRI) of the breast. MRI of the breast is sometimes used as an alternative to mammography or other screening and diagnostic tests because of its high sensitivity in detecting breast lesions, even among those women—for example, younger women and those with denser breasts—in whom mammography is less accurate. However, MRI has a high false-positive rate because of the difficulty in distinguishing between benign and malignant lesions. It is also used to look for more extensive disease in women diagnosed with breast cancer and to gauge the impact of treatment. Unfortunately, the literature on the use of CAD with MRI of the breast was sparse overall, and few studies addressed the specific situations in which CAD with MRI is used in a clinical setting. A recent TEC Asessment by BCBS found it to be experimental.

http://www.bcbs.com/betterknowledge/tec/vols/21/21_04.html

Deurloo EE, Peterse JL, Rutgers EJ et al. Additional breast lesions in patients eligible for breast-conserving therapy by MRI: impact on preoperative management and potential benefit of computerized analysis. Eur J Cancer 2005;41(10):1393-401

DeMartini WB, Lehman CD, Peacock S et al. Computer-aided detection applied to breast MRI: assessment of CAD-generated enhancement and tumor size in breast cancers before and after neoadjuvant chemotherapy. Acad Radiol 2005;12(7):806-14

MRI for back pain

The American College of Physicians (ACP) and the American Pain Society (APS) have issued a comprehensive joint clinical practice guideline for the diagnosis and treatment of low back pain, which is published in the October 2, 2007 issue of the Annals of Internal

For patients with nonspecific low back pain, clinicians should not routinely order imaging studies, including radiographs, computerized tomography (CT) scans, magnetic resonance imaging (MRI), or other diagnostic tests. These tests should be used to evaluate only those patients who have severe or progressive neurologic deficits or who are suspected to have cancer, infection, or other underlying condition as the cause of their low back pain.

For patients with nonspecific low back pain, clinicians should not routinely perform imaging studies, including radiographs, CT scans, and MRI, or other diagnostic tests (strong recommendation; moderate-quality evidence).

Patients with severe or progressive neurologic deficits, or in whom history and physical examination suggest cancer, infection, or other underlying condition as the cause of their low back pain, should undergo imaging studies and other appropriate diagnostic tests (strong recommendation; moderate-quality evidence).

Patients with persistent low back pain and signs or symptoms of radiculopathy or spinal stenosis should undergo MRI or CT only if positive results would potentially lead to surgery or epidural steroid injection for suspected radiculopathy. In choosing an imaging procedure, MRI is preferred to CT (strong recommendation; moderate-quality evidence).

Ann Intern Med. 2007;147:478-491.

MRI to evaluate breast implants

Lay Summary: MRI is indicated to evaluate possible breast implant rupture.

Women who have had previous surgery for breast cancer, have silicone implants, or have radiographically dense breasts may have inconclusive results from clinical examination, mammography, and ultrasound. When these methods of evaluation are inconclusive, the radiologist may recommend an MRI if it is likely to provide more diagnostic information. Breast MRI can often distinguish between scar tissue and recurrent cancer and its image quality is not significantly impaired by dense tissue or implants. If a clinical suspicion of silicone implant rupture exists, breast MRI is the most accurate test for evaluation. FDA recommends magnetic resonance imaging (MRI) as the current method of choice for detecting silent rupture of silicone gel-filled breast implants.

http://www.fda.gov/cdrh/ode/guidance/1239.html

Hölmich, L.R., et al. 2005b. The diagnosis of breast implant rupture: MRI findings compared to findings at explantation. 2005. Eur J. Radiol. 53: 213-25.