Bilateral Hilar Foci on 18F-FDG PET Scan in Patients Without Lung Cancer: Variables Associated with Benign and Malignant Etiology

Combined procedure with radial probe and convex probe endobronchial ultrasound

Background

Concurrent bronchoscopy using radial probe and convex endobronchial ultrasound (RP‐ and CP‐EBUS) is used to simultaneously evaluate both peripheral lung lesions for the histological diagnosis of the primary tumor and mediastinal lymph nodes for mediastinal staging. So far, little is known about the combined procedure with RP‐ and CP‐EBUS.

Methods

Between January 2020 and March 2021, the bronchoscopy database was reviewed to identify the clinical outcomes of the combined procedure with RP‐ and CP‐EBUS. Patients who underwent transbronchial biopsy using RP‐EBUS alone were classified as the RP‐EBUS group, while those who underwent a combined procedure with RP‐ and CP‐EBUS were classified as the combination group.

Results

The overall diagnostic yield of the bronchoscopic procedure in the combination group was significantly higher than the RP‐EBUS group (90.7% vs. 70.0%, p < 0.001). CP‐EBUS increased the diagnostic yield of the bronchoscopic procedure in the combination group by 9.3%. Although the mean procedure time was significantly longer, and the mean doses of midazolam and fentanyl were significantly higher in the combination group (p < 0.001), there were no differences in the overall complication rates between the two study groups (1.4% and 1.0% for the RP‐EBUS and combination groups, respectively, p = 0.766).

Conclusions

Combined bronchoscopy using RP‐ and CP‐EBUS is feasible and safe. In addition to mediastinal staging, CP‐EBUS increased the overall diagnostic yield of the bronchoscopic procedure by 9.3%.

Prognostic impact of preoperative FDG-PET positive lymph nodes in lung cancer

BACKGROUND

2-[¹⁸F] Fluoro-D-deoxyglucose positron emission tomography (FDG-PET) is an appropriate diagnostic procedure for staging lung cancer. However, accurate evaluation of lymph node (LN) metastases by PET is controversial owing to false-positive/-negative FDG uptake results. The prognostic significance of both false-negative and false-positive LNs on FDG-PET remains to be determined.

METHODS

A total of 235 patients with lung cancer were retrospectively analyzed. Maximum standardized uptake values (SUVmax) of the lymph nodes were compared with pathological LN metastases to correlate PET findings with clinicopathological variables and patients' outcomes.

RESULTS

When SUVmax ≥ 4 was defined as PET-positive for LN metastasis, sensitivity, specificity, and accuracy were 46.0%, 79.5%, and 72.3%, respectively. False-negative cases and pathological n0 cases were significantly younger, had primary tumors that were smaller or lower SUVmax, and adenocarcinomas compared with false-positive and pathological n⁺ cases. The difference in survival time between patients with abnormal FDG uptake in the LN and those without was larger than that between pathological LN metastases and no pathological metastases in patients with adenocarcinoma. Multivariate analysis by the Cox proportional hazard model identified smoker, EGFR/ALK negative and LN positive on PET as significant adverse prognostic factors, rather than pathological n-stage.

CONCLUSIONS

Abnormal FDG uptake in the LN is an important prognostic factor. Increased glucose metabolism on FDG-PET appears to be a more efficient postoperative prognostic marker than pathological n-stage in patients with lung cancer.

Clinicopathologic Significance of False-Positive Lymph Node Status on FDG-PET in Lung Cancer

INTRODUCTION

2-[¹⁸F] Fluoro-d-deoxyglucose (FDG) positron emission tomography (PET) is a relevant diagnostic procedure for staging lung cancer. However, accurate evaluation of lymph node metastases by PET is controversial because of false-positive FDG uptake.

PATIENTS AND METHODS

A total of 245 patients with lung cancer were retrospectively analyzed. Standardized maximum uptake values (SUV_max) of the primary tumor and lymph nodes were compared to pathologic lymph node metastases to correlate PET findings with clinicopathologic variables and patient outcomes.

RESULTS

The SUV_max values of metastatic lymph nodes were significantly higher than those of lymph nodes without metastases (P = .0036). When SUV_max ≥ 4 was defined as PET positive for metastasis, the sensitivity, specificity, and accuracy were 48.1%, 79.8%, and 73.1%, respectively. Multivariate logistic regression analysis showed that age > 75 years, bilateral hilar FDG uptake, and no lymph node swelling were significant factors related to false-positive lymph node metastases. Smoking status, FDG uptake in the primary tumor, and concurrent lung diseases were not significant factors.

CONCLUSION

Metastatic lymph nodes show higher FDG uptake than false-positive lymph nodes, and older patient age, bilateral hilar FDG uptake, and no swollen nodes are associated with no metastases. Patients with lymph node metastases have worse survival than those with false-positive FDG-PET findings. However, abnormal FDG uptake in the lymph node is an important prognostic factor.

Association of Otolaryngology Resident Duty Hour Restrictions With Procedure-Specific Outcomes in Head and Neck Endocrine Surgery

Importance

Graduate medical education has undergone a transformation from traditional long work hours to a restricted plan to allow adequate rest for residents. The initial goal of this restriction is to improve patient outcomes.

Objective

To determine whether duty hour restrictions had any impact on surgery-specific outcomes by analyzing complications following thyroid and parathyroid procedures performed before and after duty hour reform.

Design, Setting, and Participants

Retrospective cross-sectional analysis of the National Inpatient Sample (NIS).The NIS was queried for procedure codes associated with thyroid and parathyroid procedures for the years 2000 to 2002 and 2006 to 2008. Hospitals were divided based on teaching status into 3 groups: nonteaching hospitals (NTHs), teaching hospitals without otolaryngology programs (THs), and teaching hospitals with otolaryngology programs (THs-OTO).

Main Outcomes and Measures

Procedure-specific complication rates, length of stay, and mortality rates were collected. SAS statistical software (version 9.4) was used for analysis with adjustment using Charlson comorbidity index.

Results

Total numbers of head and neck endocrine procedures were 34 685 and 39 770 (a 14.7% increase), for 2000 to 2002 and 2006 to 2008, respectively. THs-OTO contributed a greater share of procedures in 2006 to 2008 (from 18% to 25%). With the earlier period serving as the reference, length of stay remained constant (2.1 days); however, total hospital charges increased (from $12 978 to $23 708; P < .001). Rates of postoperative hematoma (odds ratio [OR], 1.21; 95% CI, 1.06-1.38), hypoparathyroidism (OR, 1.27; 95% CI, 1.06-1.52), and unintentional vessel lacerations (OR, 1.36; 95% CI, 1.02-1.83) increased overall with NTHs (OR, 1.26; 95% CI, 1.04-1.52), THs (OR, 1.65; 95% CI, 1.15-2.37), and THs-OTO (OR, 1.98; 95% CI, 1.09-3.61) accounting for these differences, respectively. Overall mortality decreased (OR, 0.66; 95% CI, 0.47-0.94) following a decrease in the TH-OTO mortality rate (OR, 0.34; 95% CI, 0.12-0.93).

Conclusions and Relevance

While recurrent laryngeal nerve injury, hematoma formation, and hypoparathyroidism did not change, length of stay and mortality improved within THs-OTO following head and neck endocrine procedures after implementation of duty hour regulations. This finding refutes the concern that duty hour restrictions result in poorer overall outcomes. Less time available to develop technical competence may play a factor in some outcomes in lieu of recurrent laryngeal nerve injury increasing within THs and accidental injury to vessels, organs, or nerves and hypocalcemia increasing within THs-OTO. Furthermore, head and neck endocrine cases increased at THs with otolaryngology programs.

Sarcoidosis imitating breast cancer metastasis: a case report and literature review

Sarcoidosis is a benign systematic granulomatous disorder of unknown etiology and is associated with various malignancies. However, granulomatous and metastatic lymph node lesions are difficult to distinguish even when using precise and modern diagnostic methods, such as positron emission tomography. Thus, histological verification is the only method that can be used to accurately describe the nature of this disease. In this article, we report a case of non-luminal HER-2/neu-positive breast cancer in a patient without history of sarcoidosis and suspected to have metastatic disease.

The prognostic value of total lesion glycolysis via 18F-fluorodeoxyglucose PET-CT in surgically treated esophageal squamous cell carcinoma

OBJECTIVE

In addition to staging, the identification of prognostic factors is important for predicting survival in patients with esophageal cancer after esophagectomy. The present study was performed to document the prognostic role of total lesion glycolysis (TLG) in postoperative patients.

METHODS

We retrospectively reviewed the records of 50 patients with esophageal squamous cell carcinoma who underwent surgical resection and complete lymph node dissection after positron emission tomography-computed tomography (PET-CT). A volume of interest was drawn on the primary lesion and suspected metastatic lymph nodes, and the maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), TLG of the primary lesion (TLGp), and whole-body TLG (TLGwb) were measured using an SUV cutoff of 2.5.

RESULTS

The study population included 50 patients with a mean age of 63.14 ± 8.18 years: 12 (24%) were reported as stage I, 13 (26%) as stage II, and 25 (50%) as stage III. The median follow-up period was 20.46 months, and recurrences occurred in 17 patients. The mean SUVmax, MTV, TLGp, and TLGwb were 11.11 ± 6.40, 20.47 ± 22.88, 122.54 ± 180.98, and 129.37 ± 193.66, respectively. On the multivariate analysis, TLGp was a risk factor for disease-free survival (DFS) [hazard ratio (HR) = 1.002, p = 0.026], and TLGwb was a risk factor for DFS (HR = 1.002, p = 0.021) and overall survival (OS) (HR = 1.002, p = 0.044). The 3-year OS rates were 66.1% in patients with low TLGwb (≤ 41.45) and 33.3% in those with high TLGwb (>41.45; p = 0.004). The concordance index of the TLGwb was 0.752 (95% CI 0.659-0.845).

CONCLUSION

TLGwb is a significant prognostic factor for OS and DFS in patients with surgically treated esophageal squamous cell carcinoma.

Sarcoidosis Occurring After Solid Cancer: A Nonfortuitous Association: Report of 12 Cases and Review of the Literature

The association between cancer and sarcoidosis is controversial. Some epidemiological studies show an increase of the incidence of cancer in patients with sarcoidosis but only few cases of sarcoidosis following cancer treatment have been reported. We conducted a retrospective case study from internal medicine and oncology departments for patients presenting sarcoidosis after solid cancer treatment. We also performed a literature review to search for patients who developed sarcoidosis after solid cancer. We describe the clinical, biological, and radiological characteristics and outcome of these patients. Twelve patients were included in our study. Various cancers were observed with a predominance of breast cancer. Development of sarcoidosis appeared in the 3 years following cancer and was asymptomatic in half of the patients. The disease was frequently identified after a follow-up positron emission tomography computerized tomography evaluation. Various manifestations were observed but all patients presented lymph node involvement. Half of the patients required systemic therapy. With a median follow-up of 73 months, no patient developed cancer relapse. Review of the literature identified 61 other patients for which the characteristics of both solid cancer and sarcoidosis were similar to those observed in our series. This report demonstrates that sarcoidosis must be considered in the differential diagnosis of patients with a history of malignancy who have developed lymphadenopathy or other lesions on positron emission tomography computerized tomography. Histological confirmation of cancer relapse is mandatory in order to avoid unjustified treatments. This association should be consider as a protective factor against cancer relapse.

Mediastinal sarcoidosis mimicking lymph malignancy recurrence after anti-neoplastic therapy

The aim of our work is to promote the awareness about the development of sarcoidosis after antineoplastic therapy in order to avoid diagnostic errors with FDG-PET/CT findings. We report the observation of three women with breast, cervix and stomach treated cancers who developed a sarcoidosis after the end of anti-neoplastic therapy. The utility of FDG-PET/CT is in pinpointing the organs candidates for diagnostic biopsy and not distinguishing between the malignancy and granulomatous or inflammatory diseases.

Case Report of Pulmonary Sarcoidosis Suspected to be Pulmonary Metastasis in a Patient with Breast Cancer

Standard endocrine therapy and chemotherapy can induce long-term remission in breast cancer patients; however, breast cancer can recur at any site. Pulmonary nodules with lymphadenopathy in advanced cancer patients are likely to be assumed as metastases. A 44-year-old woman with a history of breast cancer was presented to our institution with abnormal findings on 18-fluorodeoxyglucose positron emission tomography imaging, which suggested lung metastasis. She had previously been diagnosed with breast cancer (T1N2M0, Stage IIIa, intraductal carcinoma, triple negative cancer). Histological analysis of the mediastinal lymph node biopsy demonstrated sarcoidosis, showing a chronic, non-caseating, granulomatous inflammation. Our case highlights the need for non-malignant diagnoses in those with prior malignancies, and the need for histological evaluations in the event of first recurrence following potentially curative therapy.

Thorax: normal and benign pathologic patterns in FDG-PET/CT imaging

This article describes the normal patterns of thoracic (18)F-fluorodeoxyglucose (FDG) biodistribution, and expands on the role of FDG-PET/computed tomography (CT) for the evaluation of patients suffering from a spectrum of benign pathologic conditions that affect the chest. The discussion addresses the applications of FDG-PET/CT imaging in a wide variety of chest-related disorders. Familiarity with the normal thoracic biodistribution of FDG, coupled with knowledge of the potential nonmalignant causes of increased FDG uptake in the chest, is essential to minimize the incidence of incorrect interpretation of FDG-PET images in daily clinical practice.

Non-neoplastic bulky mediastinal mass presentation in an adolescent patient: a case report

INTRODUCTION

Mediastinal masses in pediatric patients are very heterogeneous in origin and etiology. In the first decade of life, 70% of the mediastinal masses are benign whereas malignant tumors are more frequent in the second decade of life. Among the mediastinal masses, lymph nodes are the most common involved structures and could be enlarged due to a lymphoma, leukemia, metastatic disease, or due to infectious diseases as sarcoidosis, tuberculosis and others.

CASE PRESENTATION

We report a case of a 13-year-old Caucasian girl who came to the emergency room with a history of intermittent fever, weight loss and night sweating for at least 1 month. A radiologic image work-up presented an anterior and posterior mediastinal mass. The 18F-fluorodeoxyglucose positron emission tomography presented a high maximum standard uptake value, which directed our decision for mediastinal biopsy for diagnostic elucidation. Histologic examination described the mass as granulomatous tuberculosis. The patient was treated with anti-tuberculosis therapy and developed a full clinical recovery.

CONCLUSIONS

The present case report demonstrates that a bulky mediastinal lymphadenopathy detected on 18F-fluorodeoxyglucose positron emission tomography is not always a malignant lesion, and in countries where tuberculosis is endemic, this etiology should not be forgotten during clinical investigations. There is a need for more accurate cut-off values for this technology; meanwhile, the further investigation of patients with bulky mediastinal masses with procedures such as the open biopsy is indispensable.

New axillary lymph nodal F-18 fluoro-deoxy glucose uptake in an interim positron emission tomography scan - not always a sign of disease progression

Fluoro-deoxy glucose (FDG) is a non-specific tracer and may accumulate in non-malignant conditions causing potential pitfalls leading to false-positive interpretations of interim positron emission tomography scan. We report a case of a potential pitfall of false-positive axillary lymph nodal F-18 FDG uptake caused by injection extravasation.

FDG-PET/CT of sarcoidosis and sarcoid reactions following antineoplastic treatment

Sarcoidosis or sarcoid reactions, which appear as FDG-avid lesions in oncologic patients, need to be differentiated from disseminated malignancies. We aimed to promote awareness of development of sarcoidosis or sarcoid reactions after antineoplastic therapy to avoid diagnostic errors with FDG-PET/CT findings and assess the utility of FDG-PET/CT for follow-up. We retrospectively reviewed radiological reports of FDG-PET/CT scans performed between January 2009 and December 2011. Among oncologic patients with more than 2 FDG-PET/CT scans, those with nearly symmetrical increases in FDG uptake in the hilar or mediastinal lymph nodes were identified, and those with known sarcoidosis, concurrent diagnoses of sarcoidosis with malignancy, or histopathologically proven malignancies were excluded. Then, only those cases were selected for which sarcoidosis or sarcoid reactions were diagnosed. Four of 376 oncologic cases met the criteria. At 9 months to 6 years after antineoplastic therapy, abnormal FDG uptakes were observed in the hilar, mediastinal, abdominal, pelvic, and inguinal nodes, and/or spleen and lung parenchyma with SUVmax up to 17.7. On the basis of these findings, 1 patient received anticancer chemotherapy because of tumor recurrence suspicion. A gradual decrease in FDG uptake was observed on subsequent PET/CT scans. Sarcoidosis or sarcoid reactions should be considered in differential diagnosis of oncologic patients who have developed FDG-avid lesions any time after antineoplastic therapy. FDG-PET/CT can be used for follow-up in nondiagnostic situations to detect decreases in FDG uptake due to presence of sarcoidal granulomas.

'Go with the flow ': a review of methods and advancements in blood flow imaging

Physics has delivered extraordinary developments in almost every facet of modern life. From the humble thermometer and stethoscope to X-Ray, CT, MRI, ultrasound, PET and radiotherapy, our health has been transformed by these advances yielding both morphological and functional metrics. Recently high resolution label-free imaging of the microcirculation at clinically relevant depths has become available in the research domain. In this paper, we present a comprehensive review on current imaging techniques, state-of-the-art advancements and applications, and general perspectives on the prospects for these modalities in the clinical realm.

Dual-time-point positron emission tomography findings of benign mediastinal fluorine-18-fluorodeoxyglucose uptake in tuberculosis-endemic region

BACKGROUND

We performed dual-time-point positron emission tomography imaging in patients without evidences of mediastinal lymph node metastasis to investigate the characteristics of benign mediastinal fluorine-18-fluorodeoxyglucose (FDG) uptake.

MATERIALS AND METHODS

One-hundred and eighteen mediastinal lesions of 24 patients were included for this study. On the early and delayed positron emission tomography images, size, attenuation, maximum standardized uptake value (SUV) and retention indices (RI) were recorded for lymph node characterization.

RESULTS

The mean SUV on the early and delayed scan of 118 lymph nodes was 3.3±1.2 and 4.2±1.7, respectively. The mean RI was 26.4±24.5%. Higher FDG uptake was observed in patients with calcified nodules and bilateral FDG uptake and in lymph nodes with calcification or short-axis diameter larger than 10 mm.

CONCLUSION

In tuberculosis-endemic area, the increments of SUV or RI were frequently observed in benign mediastinal lymph nodes, and these values might not be the accurate indicators of malignant disease for mediastinal FDG uptake.

Node/aorta and node/liver SUV ratios from (18)F-FDG PET/CT may improve the detection of occult mediastinal lymph node metastases in patients with non-small cell lung carcinoma

RATIONALE AND OBJECTIVES

Research suggests that the semiquantitative determination of nodal (18)F-fluorodeoxyglucose (FDG) uptake on positron emission tomography (PET)/computed tomography (CT) may be useful for the assessment of mediastinal metastases in patients with non-small-cell lung carcinoma (NSCLC). The aim of this study was to evaluate the diagnostic ability of using different standardized uptake value (SUV) parameters in the detection of ipsilateral mediastinal (N2) disease.

MATERIALS AND METHODS

A total of 102 patients newly diagnosed with non-small-cell lung carcinoma who underwent (18)F-FDG PET/CT before surgery and had not received prior therapy were retrospectively included. All patients underwent surgical resection of the primary tumor and mediastinal lymph node dissection. On a station-based analysis, different SUV parameters (eg, mediastinal lymph node SUV, node/aorta SUV ratio, and node/liver SUV ratio) were evaluated using the histopathologic results as the reference standard. The optimal cutoff value for each SUV parameter was determined with receiver-operating characteristic curve analysis.

RESULTS

The areas under the receiver-operating characteristic curves were 0.674, 0.693, and 0.715 for node SUV, node/aorta SUV ratio, and node/liver SUV ratio, respectively (P < .05). With cutoff values of 3.15, 1.37, and 1.02 for node SUV, node/aorta SUV ratio, and node/liver SUV ratio, respectively, the sensitivity of (18)F-FDG PET/CT for N2 staging was 57.1%, 85.7%, and 71.4%, and specificity was 74.2%, 50.5%, and 61.9%.

CONCLUSIONS

Compared to node SUV alone, the use of node/aorta and node/liver SUV ratios resulted in improved detection of N2 metastases. The two SUV parameters may potentially improve the diagnostic accuracy of (18)F-FDG PET/CT for the diagnosis of N2 disease in patients with non-small-cell lung carcinoma.

Clinical utility of FDG-PET and PET/CT in non-malignant thoracic disorders

There have been several endeavors made to investigate the potential role of 2-deoxy-2-[(18)F]fluoro-D-glucose positron emission tomography (FDG-PET) (and tracers) and PET-computed tomography imaging in various benign disorders, particularly those related to thoracic structures. These various conditions can be broadly categorized into three groups: (a) infectious diseases (mycobacterial, fungal, bacterial infection), (b) active granulomatous disease such as sarcoidosis, and (c) other non-infectious/inflammatory conditions or proliferative disorders (e.g., radiation pneumonitis, post-lung transplant lymphoproliferative disorders, occupational pleuropulmonary complications, and post-surgical conditions), all of which can demonstrate varying degrees of FDG uptake on PET scans based upon the degree of inflammatory activity. This article reviews the current state of this very important application of FDG-PET imaging.

Dual-time point positron emission tomography findings of benign mediastinal lymph nodes in a tuberculosis-endemic region

PURPOSE

We performed dual-time-point positron emission tomography imaging (DTPI) in patients without evidence of mediastinal lymph node metastasis to investigate the characteristics of fluorodeoxyglucose (FDG) uptake in benign mediastinal lymph nodes.

MATERIALS AND METHODS

A total of 118 mediastinal lesions in 24 patients were included in the study. The size, attenuation, maximum standardized uptake value (SUV), and retention indices (RI) were recorded on early and delayed positron emission tomography images for lymph node characterization.

RESULTS

The mean SUVs on the early and delayed scans of 118 lymph nodes were 3.3 ± 1.2 and 4.2 ± 1.7, respectively. The mean RI was 26.4% ± 24.5%. Higher FDG uptake was observed in patients with calcified nodules and bilateral FDG uptake and in lymph nodes with calcification or a short-axis diameter >10 mm.

CONCLUSION

In a tuberculosis-endemic area, increments of SUV or RI were frequently observed in benign mediastinal lymph nodes. Therefore, these values, based on mediastinal FDG uptake, might not be accurate indicators of malignant disease.

The sarcoid-lymphoma syndrome

Whether a relationship exists between sarcoidosis and lymphoma is controversial. We present 4 patients diagnosed with sarcoidosis either during or after the treatment of lymphoma, review the data surrounding the entity known as "sarcoid-lymphoma syndrome" and discuss the diagnostic pitfalls it can present. As both entities are fluorine-18 fluorodeoxyglucose avid, histologic verification and clinical acumen are needed to avoid misdiagnosis before initiating therapy.

Concordance between four European centres of PET reporting criteria designed for use in multicentre trials in Hodgkin lymphoma

PURPOSE

To determine if PET reporting criteria for the Response Adapted Treatment in Hodgkin Lymphoma (RATHL) trial could enable satisfactory agreement to be reached between 'core' laboratories operating in different countries.

METHODS

Four centres reported scans from 50 patients with stage II-IV HL, acquired before and after two cycles of Adriamycin/bleomycin/vinblastine/dacarbazine. A five-point scale was used to score response scans using 'normal' mediastinum and liver as reference levels. Centres read scans independently of each other. The level of agreement between centres was determined assuming (1) that uptake in sites involved at diagnosis that was higher than liver uptake represented disease (conservative reading), and (2) that uptake in sites involved at diagnosis that was higher than mediastinal uptake represented disease (sensitive reading).

RESULTS

There was agreement that the response scan was 'positive' or 'negative' for lymphoma in 44 patients with a conservative reading and in 41 patients with a sensitive reading. Kappa was 0.85 (95% CI 0.74-0.96) for conservative reading and 0.79 (95% CI 0.67-0.90) for sensitive reading. Agreement was reached in 46 and 44 patients after discussion for the conservative and sensitive readings, respectively.

CONCLUSION

The criteria developed for reporting in the RATHL trial are sufficiently robust to be used in a multicentre setting.

[PET-CT with intravenous contrast in the evaluation of patients with lymphoma. Contribution to diagnostic indications]

AIM

To define the utility of intravenous contrast administration in the PET-CT (PET-CTc) in patients with lymphoma in order to determine its possible indications.

MATERIAL AND METHODS

78 patients with lymphoma were prospectively evaluated. All underwent simultaneous PET-CTc scans in a hybrid system for staging (8), evaluation of response to treatment (29), suspicion of recurrence (9) and complete remission control (48). The PET scan was acquired by a conventional method and the diagnostic CT scan was performed according to radiological protocol. Both examinations were evaluated blinded and independently, analyzing 28 anatomical locations in order to determine the degree of agreement. Final diagnosis was established by the clinician based on the histological study, results of other diagnostic techniques or clinical follow-up.

RESULTS

The final result of both techniques were concordant in 87/94 studies (92.5%). A total of 158 (36 FP) pathological locations were detected with PET-CT and 189 (71 FP) with CTc, with 72 locations being discordant between both techniques. Global sensitivity, specificity, PPV and NPV were 93%, 98%, 77% and 99%; and 94%, 97%, 62% and 99%, respectively.

CONCLUSIONS

Administration of intravenous contrast does not seem to provide any advantage in the determination of nodal and extranodal disease in lymphoma patients. The low prevalence of disease probably accounts for the limited PPV of both techniques. An increase of our sample size, with a greater homogeneity of the groups, should offer more reliable results.