Metachronous mediastinal and lung metastases from head and neck cancer: A case series, literature review and considerations for treatment

Metachronous mediastinal and lung metastases (MMLM), important sources of morbidity and mortality, in people with head and neck cancer (HNC) have received little attention. Between 1980 and 2004, 37 patients with treated HNC and MMLM diagnosed on follow-up imaging (with histological confirmation in 14 cases) were identified. The median interval from diagnosis of HNC to the appearance of MMLM was 14.5 months. The overall median survival was 4 months, and the 1-year crude survival rate (CSR) was 16%. A meaningful difference in the 1-year CSRs between the palliative radiation treated and untreated subjects (39% and 4%, respectively, p < 0.01) was observed. Because associated costs of health care utilization are considerable, and yet survival is limited, optimum management of MMLM-HNC with improvement of prognosis remains a challenge.

Horner Syndrome Secondary to Metastatic Squamous Cell Carcinoma in the Neck: A Case Series

BACKGROUND

Horner syndrome caused by metastatic squamous cell carcinoma of the head and neck is not common, and when diagnosed, may have serious clinical implications. We aim at highlighting the clinical significance of this finding.

METHODS

We retrospectively reviewed charts of 6 patients with Horner syndrome secondary to metastatic head and neck squamous cell carcinoma (HNSCC) in the neck.

RESULTS

All 6 patients had pathologically confirmed nodal metastatic HNSCC. There was one unknown primary and in the remaining 5 patients the primary tumor was identified in the oropharynx, larynx, and oral cavity. Three patients died within 1 month of diagnosis, before initiation of any treatment. One patient received radiation only while 2 patients received chemoradiation with cisplatin as the tumors were unresectable given carotid sheath involvement. Median survival was 4.5 months. Only 1 out of the 6 patients survived and had complete resolution of Horner syndrome after treatment.

CONCLUSION

This is the first case series of neck metastasis from mucosal HNSCC as an unusual cause of Horner syndrome and is usually associated with very poor prognosis.

Bone marrow metastases in salivary duct carcinoma of the parotid gland

Salivary duct carcinoma (SDC) is a rare and extremely aggressive salivary gland cancer. An 81-year-old woman with SDC underwent a total parotidectomy with facial nerve sacrifice and a neck dissection. Following surgery, she was diagnosed with disseminated bone marrow metastases. She underwent chemotherapy and trastuzumab for palliation. We present a case of SDC of the parotid which was diagnosed with disseminated bone marrow metastasis following surgery for the primary. This case also highlights the importance of having a high index of suspicion while evaluating highly aggressive tumours like SDC for any atypical findings during workup.

Successful Treatment of Richter Transformation with Ibrutinib in a Patient with Chronic Lymphocytic Leukemia following Allogeneic Hematopoietic Stem Cell Transplant

Patients with chronic lymphocytic leukemia (CLL) who progress to Richter transformation (RT) have a poor prognosis. Multi-agent chemotherapy regimens do not have good response rates. There are few case reports on the use of ibrutinib in RT. Here, we present a patient who was heavily pretreated for CLL, including allogeneic stem cell transplant, and progressed to RT. She had a mixed response to multi-agent chemotherapy and was started on ibrutinib. She had a complete response for 16 months on single-agent ibrutinib with minimal toxicity.

Follicular dendritic sarcoma masquerading as fibrosing mediastinitis

Fibrosing mediastinitis (FM) is a rare disorder resulting from abnormal immunological-mediated fibro-proliferative reaction in the mediastinum. Here, we describe a case of a 46-year-old female with an incidentally found 11×9 cm posterior mediastinal mass. Multiple biopsies of this unresectable, 18-fluorodeoxyglucose avid mass revealed marked fibrosis without any evidence of malignancy, suggesting idiopathic fibrosing mediastinitis as our initial diagnosis. Multiple interventions including a trial of steroids, fluconazole, and azathioprine to target fibrosing mediastinitis were not successful. Repeat biopsy was consistent with primary mediastinal follicular dendritic cell sarcoma. The manuscript highlights the heightened need for suspecting occult malignancies in cases of FM presenting with an indeterminate cause.

FDG PET/CT and N0 mediastinal nodal status in early stage non-small cell lung cancer: A single institution retrospective experience

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Background: The increasing use of CT and now low-dose screening CT scans for at-risk patients have led to increasing detection of lung cancer at early stages. FDG PET/CT is used as an adjunct to conventional imaging to assess loco-regional lymph node spread. However, there is a potential for false-negative results, especially in smaller lesions or early nodal involvement. The main objective of this study was to study the value of PET/CT scan to evaluate for true negative mediastinal nodes in patients with early stage NSCLC. Accurate determination of N0 status can have a significant impact on the cost-effectiveness and timely management of early stage NSCLC. Methods: Of a total of 404 patients with NSCLC managed at our facility between 2008 to 2015, 29 adult patients whose PET scan showed no or equivocal mediastinal nodal involvement and subsequently underwent surgical exploration of mediastinal lymph nodes were included in the study. Data variables that were collected included the cancer site, date of PET, node status on PET, type and date of surgery, cancer histology, and the tissue diagnosis of the sampled nodes. SAS software was used for the analysis of the data. Results: Of the 29 patients with N0 or equivocal nodes on FDG PET/CT, 7 (24.13%) had evidence of malignancy on biopsy of the surgically resected lymph nodes. No statistically significant differences were noted between the site of the neoplastic lesion, cancer histology, duration between the date of PET and the date of surgery in the true negative (TN) and false negative (FN) groups. The recurrence rate was higher in the FN group 60 % (3/5) compared to 21 % (4/19) in the TN group who had follow up for atleast 2 years. Conclusions: Our findings suggest incidence of false negative results of FDG PET/CT for evaluation of N0 nodes in early stage NSCLC is 24.13%. This is comparatively higher than false negatives rates with mediastinoscopy (5-10%) reported in other studies. Although our sample size is small, if confirmed, such a relatively high incidence of false negative results on FDG PET/CT for N0 disease supports the current recommendations for exploratory mediastinoscopy and/or surgery for definitive staging in early stage NSCLC.

Exceptional response to cetuximab monotherapy in a patient with metastatic oropharyngeal squamous cell carcinoma: a molecular insight

Background

Metastatic head and neck squamous cell carcinoma (HNSCC) carries a very poor prognosis. A better understanding of the molecular driver of the disease and the identification of biomarkers of response remain paramount for an effective personalized therapy.

Case report

We report an original case of a 56-year-old patient diagnosed with metastatic HNSCC to both kidneys, who experienced a long-lasting complete response to a single-agent cetuximab, a monoclonal antibody-targeting EGFR. Comprehensive multiplatform biomarker analysis of the tumor revealed the presence of phosphatidyl-inositol 3 kinase mutation, EGFR overexpression, and the absence of PD-1/PD-L1 expression. Since PI3K, a downstream effector of EGFR, is activated, the tumor regression may have occurred mainly through a cetuximab-induced immune-mediated response, rather than EGFR signal blockade. It is plausible that this effect was enhanced by the lack of PD-1 and PD-L1 expression.

Conclusion

Our case proposes that the absence of PD-1 and PD-L1 expression in conjunction with EGFR overexpression may correlate with better response to cetuximab in HNSCC. This hypothesis needs to be examined through a large clinical trial.

Radium-223 dichloride therapy in breast cancer with osseous metastases

Osseous metastases occur frequently in patients with breast cancer. Few options exist for bone targeted therapy for hormone refractory patients with breast cancer with progressive bone metastases. We present a case of breast cancer with osseous metastases but no visceral metastases. The patient had been treated with surgery, chemotherapy, radiation and hormonal therapy, but still had extensive symptomatic osseous metastases. She received radium-223 dichloride, a therapeutic radiopharmaceutical Food and Drug Administration (FDA) approved for castration resistant prostate cancer with bone metastases. She tolerated the therapy well with no significant adverse effects. She had an excellent response with significant pain relief obviating need for regular analgaesics. Her tumour markers also dropped significantly. Osseous metastases assessed with F-18 fluorodeoxy glucose (FDG) positron emission tomography/CT (PET/CT) and F-18 sodium fluoride (NaF) bone PET/CT) scans at baseline, after two and six cycles, also showed interval improvement in the lesions. Radium-223 dichloride could potentially be a safe and useful therapeutic option in this setting.

Acquired constricting and restricting lesions of the descending duodenum

The descending duodenum is a structure with distinct pathologic processes and anatomic relationships that requires a systematic approach to the differential diagnosis. Because of its tubular shape and fixed position in the retroperitoneum, both intrinsic duodenal and juxtaduodenal diseases are capable of producing luminal narrowing and obstruction. Duodenal lesions may be located in the mucosa or submucosa. Extraduodenal lesions may originate in adjacent structures--such as the pancreas, liver, gallbladder, colon, and lymph nodes--or from other retroperitoneal structures. Causes of duodenal obstruction include intraluminal masses, such as bezoars; duodenal inflammation, such as as peptic ulcers and Crohn disease; hematomas; and benign or malignant mucosal and intramural tumors. Pancreatic inflammation; tumors; and extrinsic compression caused by gallbladder processes, hepatic masses, retroperitoneal fluid collections, and tumors, including lymphoma, may produce duodenal obstruction. Abdominal radiography, barium studies, multidetector computed tomography, magnetic resonance imaging, and positron emission tomography may be used to depict and characterize duodenal strictures. Integration of imaging, clinical, laboratory, and endoscopic findings plays a major role in establishing a diagnosis of obstructive duodenal strictures.

Impact of Plasma Glucose Level at the Time of Fluorodeoxyglucose Administration on the Accuracy of FDG-PET/CT in the Diagnosis of Pancreatic Lesions

BACKGROUND

High fasting plasma glucose (FPG) levels before fluorodeoxyglucose (FDG) administration for positron emission tomography/computed tomography (PET/CT) might affect the accuracy of 18-fluoro-deoxy-glucose-positron emission tomography-computed tomography (FDG-PET/CT) in diagnosis of pancreatic lesions. Current guidelines require FPG levels of < 200 mg/dL before FDG administration; however, the literature on the effect of FPG levels of < 200 mg/dL on the accuracy of FDG-PET/CT is scarce.

OBJECTIVES

The aim of this study was to evaluate the effect of FPG levels of < 200 mg/dL on the accuracy of FDG-PET/CT in diagnosis of pancreatic lesions.

PATIENTS AND METHODS

In this retrospective study, 161 patients who had FDG-PET/CT for initial diagnosis of pancreatic lesions were included. Fasting plasma glucose levels before FDG administration were recorded. Accuracy of FDG-PET/CT in diagnosis of pancreatic lesions was compared between patients who were non diabetic (FPG < 126 mg/dL) and hyperglycemic (126 ≤ FPG < 200 mg/dL).

RESULTS

Thirty-four patients were hyperglycemic and 127 non diabetic. Sensitivity, specificity, positive predictive value and negative predictive value of FDG-PET/CT were 90%, 88%, 87% and 91% in non diabetic and 82%, 92%, 95% and 73% in hyperglycemic patients, respectively. Overall, the accuracy was higher in non diabetic than hyperglycemic patients (89% vs. 85%).

CONCLUSIONS

Accuracy of FDG-PET/CT for primary diagnosis of pancreatic lesions is higher in patients with FPG levels < 126 mg/dL than in patients with FPG levels between 126 and 200 mg/dL.

Radium-223 dichloride bone-targeted alpha particle therapy for hormone-refractory breast cancer metastatic to bone

Background

Hormone-refractory breast cancer metastatic to bone is a clinically challenging disease associated with high morbidity, poor prognosis, and impaired quality of life owing to pain and skeletal-related events. In a preclinical study using a mouse model of breast cancer and bone metastases, Ra-223 dichloride was incorporated into bone matrix and inhibited proliferation of breast cancer cells and differentiation of osteoblasts and osteoclasts (all P values < .001) in vitro. Ra-223 dichloride also induced double-strand DNA breaks in cancer cells in vivo.

Methods

The US Food and Drug Administration recently approved radium-223 (Ra-223) dichloride (Ra-223; Xofigo injection) alpha-particle therapy for the treatment of symptomatic bone metastases in patients with castration-resistant prostate cancer. On the basis of a strong preclinical rationale, we used Ra-223 dichloride to treat bone metastases in a patient with breast cancer.

Results

A 44-year-old white woman with metastatic breast cancer who was estrogen receptor–positive, BRCA1-negative, BRCA2-negative, PIK3CA mutation (p.His1047Arg) positive presented with diffuse bony metastases and bone pain. She had hormone refractory and chemotherapy refractory breast cancer. After Ra-223 therapy initiation her bone pain improved, with corresponding decrease in tumor markers and mixed response in ¹⁸F-FDG PET/CT and ¹⁸F-NaF bone PET/CT. The patient derived clinical benefit from therapy.

Conclusion

We have shown that Ra-223 dichloride can be safely administered in a patient with hormone-refractory bone metastasis from breast cancer at the US FDA–approved dose for prostate cancer. Furthermore, because the treatment did not cause any drop in hematologic parameters, it has the potential to be combined with other radiosensitizing therapies, which may include chemotherapy or targeted therapies. Given that Ra-223 dichloride is already commercially available, this case report may help future patients and provide a rationale for initiating clinical research in the use of Ra-223 dichloride to treat bone metastasis from breast cancer. A randomized clinical trial is needed to provide evidence of efficacy, safety, and good outcomes.

Accuracy of multi-detector computed tomography, fluorodeoxyglucose positron emission tomography-CT, and CA 19-9 levels in detecting recurrent pancreatic adenocarcinoma

CONTEXT

We compared the accuracy of fluorodeoxyglucose positron emission tomography-CT (FDG-PET-CT), multi-detector computed tomography (MDCT) and CA 19-9 levels in detecting pancreatic cancer recurrence in patients with resected CA 19-9 positive pancreatic adenocarcinomas.

METHODS

We retrospectively evaluated 122 patients with pancreatic adenocarcinomas who underwent surgical resection of the tumor between January 2002 and December 2011. Twenty-five patients had MDCT, FDG-PET-CT and CA 19-9 levels performed no less than six weeks post-operation and within 8 weeks of each other for detection of tumor recurrence. Of these, 20 patients had high pre-operative CA 19-9 levels that dropped to a normal level postoperatively which will be the focus of this study. The sensitivity, specificity, positive and negative predictive value (PPV, NPV), and accuracy of MDCT, FDG-PET-CT, and CA 19-9 in detecting recurrence were compared.

RESULTS

Operations performed included pyloric sparing pancreaticoduodenectomy (n=9), pancreaticoduodenectomy (n=7), distal pancreatectomy (n=3) and total pancreatectomy (n=1). Three patients had no recurrence, but local recurrence and distant metastasis were seen in 8 (40%) and 12 (60%) patients, respectively. In our study, sensitivity, specificity, PPV, NPV and diagnostic effectiveness (accuracy) were: 82%, 100%, 100%, 50%, 85% for MDCT; 82%, 100%, 100%, 50%, 85% for FDG-PET-CT and 94%, 100%, 100%, 75%, 95% for CA 19-9. The difference in recurrence detection accuracy of the tests was not statistically significant. A combination of CA 19-9 with MDCT or FDG-PET-CT was 100% accurate in detecting cancer recurrence in our patients.

CONCLUSION

Our data suggests that CA 19-9 levels can be used reliably to detect recurrent pancreatic adenocarcinomas in patients with CA 19-9-positive primary tumors. Combination of CA 19-9 with MDCT or FDG-PET-CT is potentially the most accurate approach in detecting pancreatic cancer recurrence.

Cervical cancer outcomes with the elimination of access to care disparities

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Background: Previous studies suggest lack of insurance and quality of care variations may drive disparities in cervical cancer (CC) survival, while equitable care may close these gaps. SEER based CC mortality between 2005-9 amongst white (W) and black (B) patients (pts) was 2.2 and 4.3/100,000 respectively. To define the role of equitable care on racial disparities we selected a population of pts with CC treated irrespective of the insurance status at the Feist-Weiller Cancer Center (FWCC). We hypothesized that disparities would be less pronounced at FWCC due to equitable care. Methods: A retrospective cohort study of 151 pts with FIGO Stage I-IV cervical cancer who had clinical staging, PET imaging and treatment at FWCC between 2005-9. Collected information included age, race, date of diagnosis, histology, stage, retroperitoneal lymph node (RPLN) status, treatment received, distance from the cancer center and payer status. The treatment parameters and outcomes were compared between ethnic and financial groups. Overall survival (OS) was assessed by using the Kaplan-Meier method and compared by log rank test. Results: Patients included 88 B, 66 W and 3 other pts with median age 46 years (23 – 84). Payer status included 45% uninsured, 35% medicaid, 15% medicare, and 5% other insurance. Histological type, stage, distance from treatment center and RPLN were equally distributed between groups. All pts completed standard treatment. There was no difference in PFS (p = 0.80) and OS (p = 0.23) between ethnic groups. In concordance with prior studies the following were associated with decreased OS; non-squamous histology, 15% pts (p=0.05), advanced stage (1b2-IV; p=0.04) and RPLN on imaging, 7% pts (p=0.008). Conclusions: Cervical cancer disparities are differentially distributed across the US hospital systems. There were no disparities identified at our institution relative to payer status with all pts receiving currently recommended treatment standards. Our findings indicate that delivery of equitable care can eliminate survival differences. Future research should assess the effect of emerging Accountable Care Organizations on the elimination of racial disparities in cancer treatment outcomes.

SUV max of the most intense lesion on fdgpet/CT scan at baseline as a potential prognostic factor in stage IV (NSCLC): A retrospective review

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Background: Lung cancer is the leading cause of mortality in United States and worldwide. Stage IV lung cancer has poor prognosis with 5-year survival of 2%. Limited numbers of factors are known to predict survival in stage IV NSCLC (Non Small Cell Lung Cancer) including stage at diagnosis, Performance Status (PS), genomic expression profile. Earlier studies have found SUV max (Maximum Standardized Uptake Value) of primary lung tumor on FDGPET/CT (Fluoro Deoxy Glucose –Positron Emission Tomography/Computed Tomography) correlates with tumor doubling time and survival. However prior studies included stage I-IV NSCLC patients and SUVmax of primary lung tumor. Hence we performed this study with only clinical stage IVNSCLC who underwent FDGPET/CT scan at baseline to determine whether SUVmax value of most intense lesion has any prognostic significance. Methods: Retrospective review identified 46 patients (September 2004- September 2011) that were diagnosed with stage IV NSCLC at our institution. SUVmax of most intense lesion on FDG PET/CT scan was determined utilizing an automated program on a dedicated PET/CT workstation by a single nuclear medicine specialist. Cox regression analysis and Log-rank test were used to analyze data. Results: Descriptive statistics: Median age 61.6 (43.8-77.8), Females 17 (36%), African Americans 26 (56%), Performance status 0-1=36 (80%), number of metastatic sites 1-2=30 (65%), Adenocarcinoma 32 (70%), Chemotherapy 31 (61%), SUV max- primary (65%), other sites (35%). The patient population was subdivided into two groups using the median SUVmax of 17.8. The median survival of patients having SUV max ≤17.8 and SUVmax > 17.8 was 13.4 months and 4.5 months respectively (P =0.0269). Multivariate analysis indicated PS (HR=2.8), any chemotherapy (HR=2.56) and SUV max ≤ 17.8 (HR=1.98, P=0.04) predicted survival. Conclusions: SUV max of the most intense lesion at the time of presentation predicts worse outcome in stage IVNSCLC and needs to be validated in a prospective study. PETCT may be able to predict the areas that harbor resistant clones of cells, described in previous studies as tumor heterogeneity, which may confer prognostic significance.

Chemoradiotherapy for unresectable stage IVB head and neck cancer

OBJECTIVE

As the occurrence of unresectable stage IVB head and neck cancer is expected to continue, we present our experience over the last 17 years with chemoradiotherapy management of 14 cases to clarify the effectiveness and safety of this treatment scheme.

METHOD

Of the 1,267 individuals who were diagnosed with carcinoma of the upper aerodigestive tract between 1992 to 2008, 14 patients were treated by induction chemotherapy followed by concurrent chemoradiation or simultaneous chemoradiotherapy for stage IVB disease. The median follow-up time was 54.5 months.

RESULTS

The complete objective response rate was 79%. Six individuals remained disease-free during a followup period ranging from 24 to 149 months. The disease-free survival rate at five years was 68%. Local, regional, and distant failure rates were 21%,14%, and 7% respectively. Most of the patients (79%) experienced transient mucositis during treatment. Significant late complications consisted of dental caries or osteoradionecrosis (14%) and esophageal stricture (7%).

CONCLUSION

Definitive chemoradiotherapy administered for unresectable stage IVB head and neck cancer has the potential of achieving long-term disease-free survival in up to two-thirds of the patients with a low risk of complications.

Early Detection of Brain Pathology Suggestive of Early AD Using Objective Evaluation of FDG-PET Scans

The need for early detection of AD becomes critical as disease-modifying agents near the marketplace. Here, we present results from a study focused on improvement in detection of metabolic deficits related to neurodegenerative changes consistent with possible early AD with statistical evaluation of FDG-PET brain images. We followed 31 subjects at high risk or diagnosed with MCI/AD for 3 years. 15 met criteria for diagnosis of MCI, and five met criteria for AD. FDG-PET scans were completed at initiation and termination of the study. PET scans were read clinically and also evaluated objectively using Statistical Parametric Mapping (SPM). Using standard clinical evaluation of the FDG-PET scans, 11 subjects were detected, while 18 were detected using SPM evaluation. These preliminary results indicate that objective analyses may improve detection; however, early detection in at-risk normal subjects remains tentative. Several FDA-approved software packages are available that use objective analyses, thus the capacity exists for wider use of this method for MCI/AD.

Alzheimer’s disease detection with objective statistical evaluation of FDG-PET brain scans: essential methodology for early identification

The anticipated introduction of disease-modifying agents for the treatment of Alzheimer’s disease (AD) highlights the need for its early and accurate detection. This article provides an overview of the objective statistical voxel-based image processing and analyses technology that make early detection of AD with 18F-fluorodeoxyglucose (FDG)-PET possible. Our report demonstrates that the comparison of a single FDG-PET scan with a group of control scans provides an objective statistical map that is useful for the detection of early stages of AD, augmenting visual inspection of the PET image itself. The need for early detection of AD, together with the power of voxel-based statistical analyses, provides an impetus for agencies to re-evaluate FDG-PET as an approved methodology for the early diagnosis of AD. The expected approval of disease-modifying agents for the treatment of AD places more emphasis on the need for earlier diagnosis of this common and devastating disorder.

Potential value of quantitative analysis of cerebral PET in early cognitive decline

BACKGROUND

In patients diagnosed with Alzheimer's disease, positron emission tomography brain scans can have characteristic hypometabolic patterns that strongly support this diagnosis, but this pattern is often subtle or absent in early stages. A sensitive and objective method for detection of positron emission tomography abnormalities may have value in early detection of Alzheimer's disease.

METHODS

A 2-fluoro-2-deoxy-D-glucose positron emission tomography scans from cognitively impaired patients (n = 43) were compared individually to 28 normal controls using statistical parametric mapping, hypometabolic regions visualized, and clinically correlated. The objective SPM results were compared to the official Nuclear Medicine report based upon subjective interpretation criteria.

RESULTS

A total of 22/43 had abnormalities per the Nuclear Medicine physician, while 21/43 appeared normal. The objective analysis detected abnormalities in 41/43 participants, including 19 of 21 that appeared normal. In these 19, 8 had findings consistent with early Alzheimer's disease.

CONCLUSION

Objective analysis of positron emission tomography brain scans may extend the ability to detect early brain abnormalities in patients with cognitive decline.

F-18 FDG-PET imaging and correlation with CT in staging and follow-up of pediatric lymphomas

BACKGROUND

We hypothesized that F-18 FDG-PET could be a useful, functional imaging modality for assessing the initial staging, response to therapy and follow-up of children diagnosed with lymphoma.

OBJECTIVE

To assess the role of whole-body F-18 FDG-PET imaging in patients with lymphoma as an initial staging modality and to measure its predictive value for monitoring the response to therapy and disease recurrence compared to CT and clinical follow-up studies.

MATERIALS AND METHODS

As part of their routine clinical care, 24 patients with histologically proven lymphoma (18 Hodgkin disease and 6 non-Hodgkin lymphoma) underwent an F-18 FDG-PET and a CT scan. A total of 28 studies were performed and the entire set of scans retrospectively reviewed. Seven studies were performed for initial staging, 12 for monitoring therapy response and 9 for detecting recurrence. Initial diagnosis was confirmed by histopathology while the gold standard at follow-up was established by clinical follow-up, additional imaging modalities and/or biopsy. F-18 FDG-PET was visually compared to CT on a lesion-by-lesion basis. Fifteen anatomic regions (seven nodal and eight extranodal) were analyzed.

RESULTS

Of the 414 regions analyzed, PET and CT were concordant in 366 (positive in 16 and negative in 350). Discordance was found in 48 regions. Overall sensitivities, specificities, and positive and negative predictive values were 78%, 98%, 94% and 90% for F-18 FDG-PET and 79%, 88%, 90% and 46% for CT, respectively.

CONCLUSION

F-18 FDG-PET imaging is a useful technique for the staging and follow-up of pediatric patients with lymphoma.

PET in cardiology

Myocardial perfusion imaging with single-photon emission CT (SPECT) is a key investigation in the work-up of patients with coronary artery disease. PET, however, with inherently better spatial and temporal resolution, offers several advantages over SPECT. The last decade has witnessed extensive application of PET techniques to assess myocardial viability and has provided valuable information important in analyzing the risk: benefit ratio for several therapeutic measures. Recent advances in PET instrumentation and radiopharmaceuticals have generated considerable interest to use PET for evaluating an array of cardiovascular disease.

18F-FDG PET in evaluation of adrenal lesions in patients with lung cancer

The purpose of this study was to assess the role of PET with (18)F-FDG in differentiating benign from metastatic adrenal masses detected on CT or MRI scans of patients with lung cancer.

METHODS

This retrospective study analyzed (18)F-FDG PET scans of patients with lung cancer who were found to have an adrenal mass on CT or MRI scans. One hundred thirteen adrenal masses (75 unilateral and 19 bilateral; size range, 0.8-4.7 cm) were evaluated in 94 patients. PET findings were interpreted as positive if the (18)F-FDG uptake of the adrenal mass was greater than or equal to that of the liver. PET findings were interpreted as negative if the (18)F-FDG uptake of the adrenal mass was less than that of the liver. All studies were reviewed independently by 3 nuclear medicine physicians, and the results were then correlated with clinical follow-up or biopsy results when available.

RESULTS

PET findings were positive in 71 adrenal masses. Sixty-seven of these were eventually considered to be metastatic adrenal disease. In the remaining 4, no changes in lesion size were noted on follow-up examinations. PET findings were negative in 42 adrenal masses, of which 37 eventually proved to be benign. Among the 5 adrenal masses that were false-negative, one was a large necrotic metastasis; 1 was a 2.4-cm lesion with central hemorrhaging, and the remaining 3 were lesions of less than 11 mm. The sensitivity, specificity, and accuracy for detecting metastatic disease were 93%, 90%, and 92%, respectively.

CONCLUSION

(18)F-FDG PET is an accurate, noninvasive technique for differentiating benign from metastatic adrenal lesions detected on CT or MRI in patients with lung cancer. In addition, PET has the advantage of assessing the primary cancer sites and detecting other metastases.