Revisiting the prognostic role of gallium scintigraphy in low-grade non-Hodgkin's lymphoma

Underperformance of gallium-67 scan is greater in relapse than in initial staging, compared with FDG PET

PURPOSE

The purpose of this study is to evaluate the performance of gallium-67 scan (GS) and F-18 fluorodeoxyglucose (FDG) PET scan in lymphoma staging and recurrence detection by comparing the 2 imaging studies in the same patient.

MATERIALS AND METHODS

A total of 42 patients from the period between July 2002 and May 2006 were included in this study. Of the 42 patients, 6 had Hodgkin disease and 36 had non-Hodgkin lymphomas. All of them underwent one or more FDG PET scans and also underwent corresponding GS performed within 7 days of FDG PET, for staging or detection of lymphoma recurrence. Among the non-Hodgkin lymphoma cases, 18 were diffuse large B-cell lymphoma, 10 were follicular center cell lymphoma, and 8 were of other types. Of the total 46 pairs of imaging performed in these 42 patients, 27 were for staging, and 19 for restaging after recurrence.

RESULTS

In all these studies, FDG PET detected 230 lesion sites, whereas GS detected 85 lesion sites. All of the lesions detected by GS were noted on FDG PET, whereas GS detected only 37.0% of the lesions detected by FDG PET. Among the 27 studies for staging, FDG PET detected 120 lesions, whereas GS detected 68 lesions (56.7%). In the 19 images taken for relapse, FDG PET detected 110 lesions, whereas GS detected only 17 (15.5%).

CONCLUSIONS

FDG PET is superior to GS in staging and detecting all types of lymphoma. The difference is notably more significant in recurrence detection.

The usefulness of (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG-PET) and a comparison of (18)F-FDG-pet with (67)gallium scintigraphy in the evaluation of lymphoma: relation to histologic subtypes based on the World Health Organization classification

BACKGROUND

Although studies comparing conventional imaging modalities with (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG-PET) for the detection of lymphoma and although the relations between (18)F-FDG-PET and histologic types were reported previously, most studies were not systematic and involved relatively small numbers of patients.

METHODS

Two hundred fifty-five patients with lymphoma had their disease staged using (18)F-FDG-PET, and 191 of those patients also were assessed using gallium-67 scintigraphy ((67)Ga). Disease sites were identified on a site-by-site basis using computed tomography scans and/or magnetic resonance imaging. The results of these conventional imaging modalities were compared with the results from (8)F-FDG-PET and (67)Ga, and correlations between the imaging results and pathologic diagnoses were evaluated by using the World Health Organization classification system.

RESULTS

Of 913 disease sites in 255 patients, (18)F-FDG-PET identified >97% of disease sites of Hodgkin lymphoma (HL) and aggressive and highly aggressive non-Hodgkin lymphoma. For indolent lymphoma, the detection rate of (18)F-FDG-PET was 91% for follicular lymphoma (FL); 82% for extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue, irrespective of plasmacytic differentiation; and approximately 50% for small lymphocytic lymphoma (SLL) and splenic marginal zone lymphoma (SMZL). The results from (67)Ga were similar to those from (18)F-FDG-PET for most histologic subtypes. However, the sensitivity of (67)Ga was unexpectedly poor for FL, for mantle cell lymphoma (MCL), and for the nasal type of natural killer/T-cell lymphoma (NK/T-nasal), ranging from 30% to 38%.

CONCLUSIONS

(18)F-FDG-PET was useful for all histologic subtypes of lymphoma other than SLL and SMZL. Compared with (67)Ga, the authors strongly recommend the use of (18)F-FDG-PET in patients with FL, MCL, and NK-nasal.

A 18F-FDG-positive, 67Ga-negative, and transferrin receptor expression-negative patient with diffuse large B-cell lymphoma

We recently experienced a case with uveitis suffering from fever of unknown origin suspected of being caused by sarcoidosis. Chest computed tomography showed right supraclavicular, bilateral mediastinal, and right hilar lymphadenopathy, and intensive abnormal uptake of 2-[18F]fluoro-2-deoxy-D-glucose (18F-FDG) was observed on positron emission tomography with 18F-FDG (FDG-PET). On the other hand, 67Ga scintigraphy showed almost no abnormal findings. Histopathological examination revealed the lesion to be a diffuse large B-cell lymphoma (DLBCL), namely, an aggressive non-Hodgkin lymphoma from a right supraclavicular lymph node biopsy specimen. Additional immunohistochemical analysis showed the negative expression of transferrin receptor (TfR) on the formalin-fixed paraffin-embedded specimen. Although DLBCL is generally considered to be a 67Ga-avid tumor, it does not always have a large number of TfRs and that leads to a discrepancy between the 67Ga scintigraphy and FDG-PET findings. FDG-PET should be more appropriate for the initial staging of DLBCL than 67Ga scintigraphy, whereas 67Ga scintigraphy might be able to provide additional information including prognostic factors and to support strategies that target TfR for cancer therapy.

The role of FDG-PET scans in patients with lymphoma

18-Fluoro-deoxyglucose positron emission tomography (FDG-PET) is a noninvasive, 3-dimensional imaging modality that has become widely used in the management of patients with malignant lymphomas. This technology has been demonstrated to be more sensitive and specific than either (67)gallium scintigraphy or computerized tomography, providing a more accurate distinction between scar or fibrosis and active tumor. PET scans have been evaluated in pretreatment staging, restaging, monitoring during therapy, posttherapy surveillance, assessment of transformation, and, more recently, as a surrogate marker in new drug development. Data to support these various roles require prospective validation. Moreover, caution must be exercised in the interpretation of PET scans because of technical limitations, variability of FDG avidity among the different lymphoma histologic subtypes, and in the large number of etiologies of false-negative and false-positive results. Recent attempts to standardize PET in clinical trials and incorporation of this technology into uniformly adopted response criteria will hopefully lead to improved outcome for patients with lymphoma.

Utility of fluorodeoxyglucose-PET imaging in the management of patients with Hodgkin's and non-Hodgkin's lymphomas

FDG-PET imaging has a number of advantages in the management of patients with lymphoma. PET shows a functional metabolic status and gives quantitative information. In addition, PET provides whole-body images that give a comprehensive assessment of disease extent during the staging and followup. Based on the present literature, FDG-PET is at least equivalent to CT for the initial staging of lymphomas. The impact of new technologies of combined PET/CT and fast-scanning CT with contrast has yet to be evaluated in the management of lymphoma patients, however. At this point, FDG-PET and CT must be considered as giving complementary staging information. FDG-PET also has high diagnostic accuracy for restaging lymphoma after initial treatment. FDG-PET has shown high accuracy in the early prediction of response to chemotherapy and in the evaluation of residual masses after chemotherapy or radiation therapy. Therefore, PET is likely to play a major role in tailoring the intensity of the treatment to the individual patient. A pretreatment FDG-PET study is essential for accurate assessment of residual masses and early monitoring of response to the treatment. In addition, a baseline PET scan will help detect relapse or residual disease, because relapse occurs most often in the region of previous disease.

18p-FDG PET is superior to67Ga SPECT in the staging of non-Hodgkin’s lymphoma

OBJECTIVE

Our study aims to compare diagnostic accuracy between 18F-FDG PET and 67Ga SPECT in the staging of non-Hodgkin's lymphoma.

METHODS

Twenty-eight patients with non-Hodgkin's lymphoma, underwent 18F-FDG PET, 67Ga SPECT and CT for the pretreatment staging of malignant lymphoma between August 1999 and March 2002. 18F-FDG PET imaging was obtained 60 minutes after the intravenous administration of 185 MBq of 18F-FDG. 67Ga SPECT imaging was obtained 2 days after the intravenous administration of 148 MBq of 67Ga. 18F-FDG PET and 67Ga SPECT were performed within one month. Both imagings were performed on the area from the neck to the pelvis. The 18F-FDG PET and 67Ga SPECT findings were compared with the CT findings and the clinical course.

RESULTS

Sixty-six nodal lesions were clinically confirmed. Of these, 32 were identified by both 18F-FDG PET and 67Ga SPECT. The remaining 34 lesions were identified only by 18F-FDG PET. The mean (+/- SD) sizes' of the nodes were 34.7 +/- 32.4 mm for 18F-FDG-positive and 67Ga-positive lesions and 15.7 +/- 8.3 mm for 18F-FDG-positive and 67Ga-negative lesions (p < 0.001). Of the 23 extranodal lesions, 12 were identified by both 18F-FDG PET and 67Ga SPECT, whereas 6 lesions were identified by only 18F-FDG PET. Five lesions were not identified by either technique. No 18F-FDG-negative but 67Ga-positive nodal or extranodal lesions were observed. The difference in findings between the two studies is related to the difference in the size but not in the histology or site of the lesions.

CONCLUSION

18F-FDG PET detected significantly more lesions particularly small lesions than 67Ga SPECT. Thus, 18F-FDG PET is considered to be superior to 67Ga SPECT in the staging of non-Hodgkin' s lymphoma.

111In-DOTA- dPhe1-Tyr3-octreotide, 111In-DOTA-lanreotide and 67Ga citrate scintigraphy for visualisation of extranodal marginal zone B-cell lymphoma of the MALT type: a comparative study

Somatostatin receptor (SSTR) scintigraphy and gallium-67 citrate ((67)Ga) scintigraphy have been used for visualisation of Hodgkin's lymphoma and non-Hodgkin's lymphoma. However, experience with B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT) type is very limited. The aim of this study was to prospectively compare the (67)Ga scintigraphy results with those obtained by (111)In-DOTA- dPhe(1)-Tyr(3)-octreotide ((111)In-DOTA-TOCT) and (111)In-DOTA-lanreotide ((111)In-DOTA-LAN) scintigraphy in patients with proven MALT-type lymphoma. Comparative scintigraphic examinations using (67)Ga, (111)In-DOTA-TOCT and (111)In-DOTA-LAN were performed in 18 patients (11 female and 7 male, median age 64+/-15 years) with histologically verified MALT-type lymphomas of various origin. Planar and single-photon emission tomography imaging acquisitions were performed after injection of a mean dose of 185+/-26 MBq (67)Ga and 165+/-20 MBq (111)In-DOTA-TOCT or (111)In-DOTA-LAN. All scintigraphic results were correlated with other conventional examinations including gastroscopy, colonoscopy, endosonoscopy, ophthalmologic investigation, CT of the thorax and abdomen and bone marrow biopsy. This comparative study showed that (67)Ga scintigraphy found abnormalities in 10 of 16 patients (63%) and detected 18 of 31 clinically involved sites (58%), but was false positive in three patients. (111)In-DOTA-TOCT found abnormalities in 9 of 15 patients (60%) and detected 15 of 27 clinical lesions (56%); it was false positive in two patients. (111)In-DOTA-LAN scintigraphy showed abnormalities in 7 of 11 patients (64%) and found 12 of 22 clinical lesions (55%). False-positive (111)In-DOTA-LAN scan results were found in two patients. For supra-diaphragmatic lesions, (67)Ga scintigraphy detected 12 of 16 sites (75%). (111)In-DOTA-TOCT scintigraphy revealed 7 of 15 lesions (47%). (111)In-DOTA-LAN showed 6 of 12 positive sites (50%). For infra-diaphragmatic involvement, the sensitivities of (67)Ga, (111)In-DOTA-TOCT and (111)In-DOTA-LAN were 40%, 67% and 60%, respectively. It is concluded that MALT-type lymphoma can be visualised by (67)Ga, (111)In-DOTA-TOCT and (111)In-DOTA-LAN scintigraphy. Although there were no statistically significant differences in patient-related and site-related sensitivities when using (67)Ga compared with (111)In-DOTA-TOCT and (111)In-DOTA-LAN, the sensitivity of (67)Ga tended to be superior to that of (111)In-DOTA-TOCT and (111)In-DOTA-LAN for supra-diaphragmatic lesions but inferior for infra-diaphragmatic involvement. In selected cases, the combination of (67)Ga and (111)In-DOTA-LAN or (111)In-DOTA-TOCT may increase the diagnostic efficiency in patients with MALT-type lymphoma.

Gallium-67 scintigraphy: a cornerstone in functional imaging of lymphoma

Until recently, gallium-67 scintigraphy (GS) has been the best available functional imaging modality for evaluating patients with non-Hodgkin's lymphoma (NHL) and Hodgkin's disease (HD). The diagnostic accuracy of GS in detecting lymphoma is based on optimisation of the imaging protocol, knowledge of potential physiological and benign sites of (67)Ga uptake, and the Ga avidity characteristics of the individual lymphoma. As (67)Ga is a tumour viability agent, the role of GS is primarily at follow-up. A residual mass persisting on CT after treatment poses a common clinical dilemma: it may indicate the presence of viable lymphoma, which requires further treatment, or it can be benign, consisting of only fibrotic and necrotic tissues. GS can successfully differentiate between these conditions. Routine follow-up with GS may allow early diagnosis of recurrence and early institution of treatment. Reversion of a positive GS to a negative test, and the rapidity with which this occurs has a high predictive value for the outcome of the individual patient. Lymphoma showing a normal GS early during treatment has a better prognosis than lymphoma with persistence of pathological findings. Other tumour-seeking single-photon emitting agents, such as thallium-201, technetium-99m methoxyisobutylisonitrile and indium-111 octreotide, have been investigated in lymphoma, primarily as an alternative to GS in specific clinical settings, but are of limited value. The role of radioimmunoscintigraphy is gaining importance in conjunction with radioimmunotherapy. Fluorine-18 fluorodeoxyglucose (FDG) imaging of lymphoma using either dedicated or camera-based PET systems is gradually replacing GS for assessment of lymphoma. FDG overcomes some of the limitations of GS while sharing its tumour viability characteristics. The extensive clinical knowledge and experience accumulated over three decades with GS in lymphoma provides a solid background as well as a model for the assessment of new functional imaging techniques.

Scintigraphic findings of MALT lymphoma of the thyroid

Mucosa-associated lymphoid tissue (MALT) lymphoma has been established as a distinct entity among non-Hodgkin's lymphomas, and the most common primary site is the stomach. We describe scintigraphic findings in a patient with MALT lymphoma of the thyroid. A 71-year-old woman with Hashimoto's thyroiditis suffered from rapid cervical swelling, and ultrasonography and CT revealed a thyroid nodule. The nodule showed accumulation of 99mTc pertechnetate comparable to the surrounding thyroid tissue, mimicking a benign nodule. Both 67Ga and 201Tl imaging visualized the lesion as an increased uptake area. After radiotherapy, abnormally increased uptake disappeared on 67Ga images, which predicted a favorable outcome. MALT lymphoma of the thyroid may be visualized as a warm nodule on 99mTc pertechnetate scintigraphy.

Comparison of fluorine-18 fluorodeoxyglucose positron emission tomography and Ga-67 scintigraphy in evaluation of lymphoma

BACKGROUND

The accuracy of fluorodeoxyglucose positron emission tomography (FDG-PET; dual-head camera with attenuation correction) and Ga-67 scintigraphy was compared to identify disease sites in patients with Hodgkin disease (HD) and intermediate and high-grade non-Hodgkin lymphoma (NHL) at initial diagnosis or clinical recurrence.

METHODS

Fifty-one contemporaneous FDG-PET and Ga-67 scintigraphies were performed on patients with NHL (35 intermediate grade, 3 high grade) or HD (13 patients). Sites of disease were correlated on a site-by-site basis on FDG-PET and Ga-67 images. Tumor-to-background (T/B) ratios were obtained for both techniques. Discordant FDG-PET and Ga-67 findings were correlated with computed tomography findings or clinical evaluation including repeat FDG-PET scans obtained after therapy.

RESULTS

Fluorodeoxyglucose positron emission tomography was positive at all 158 sites in 51 patients compared with 113 sites in 41 positive studies with Ga-67 scintigraphy (single positron emission computed tomography [SPECT] and/or planar images). In 44 patients who had complete Ga-67 SPECT data on all tumor sites, FDG-PET was positive at 126 sites and Ga-67 SPECT was positive at 81 sites. Ga-67 SPECT failed to demonstrate disease at 45 sites (35.7%). In 10 of 44 patients, Ga-67 SPECT completely failed to detect any disease at 22 of 45 sites (17.5%) and partially identified disease sites at 23 of 45 sites (18.2%) in 11 patients regardless of the tumor site and histology. In these patients, the lesions measured between 0.6 and 14.0 cm by CT. Fluorodeoxyglucose positron emission tomography revealed higher stage disease in 13 patients compared with Ga-67 imaging. Tumor-to-background ratios were statistically different between the two techniques with higher ratios obtained with FDG-PET (P < 0.0001).

CONCLUSIONS

In imaging aggressive lymphoma and HD before therapy, FDG-PET has significantly higher site and patient sensitivity than Ga-67 scintigraphy (100% vs. 71.5% and 100% vs. 80.3%, respectively). The change in disease stage by FDG-PET may result in a change in therapy strategy.

Fluorine-18 fluorodeoxyglucose positron emission tomography, gallium-67 scintigraphy, and conventional staging for Hodgkin's disease and non-Hodgkin's lymphoma

PURPOSE

To compare fluorine-18 fluorodeoxyglucose positron emission tomography (PET) and gallium scanning with each other and with conventional staging, for patients with Hodgkin's disease or non-Hodgkin's lymphoma.

SUBJECTS AND METHODS

Fifty patients had PET, gallium scanning, and conventional staging of newly diagnosed or progressive Hodgkin's disease or non-Hodgkin's lymphoma. Disease sites, stage, and treatment plans were assessed retrospectively.

RESULTS

Positron emission tomography and gallium scanning each upstaged 14% of patients (n = 7). Management was altered by PET in 9 cases (18%) and by gallium scanning in 7 (14%, P = 0.6). Disease was evident in 117 sites in 42 patients. The case positivity rate for conventional assessment was 90%; for PET, 95%; for gallium scanning, 88%; for conventional assessment plus PET, 100%; and for conventional assessment plus gallium scanning, 98%. Site positivity rates for conventional assessment were 68%; for PET, 82%; for gallium scanning, 69% (conventional vs. PET, P = 0.01; conventional vs. gallium scanning, P = 0.9; PET vs. gallium scanning, P = 0.01); for conventional assessment plus PET, 96%; and for conventional assessment plus gallium scanning, 94%. Positron emission tomography and gallium scanning were entirely concordant in 31 patients; in the other 19 patients, PET identified 25 sites missed by gallium scanning, whereas gallium scanning identified 10 sites missed by PET.

CONCLUSION

In this retrospective study, PET demonstrated a higher site positivity rate than did gallium scanning, with similar case positivity rates. These data support the use of PET in place of gallium scanning for the staging of patients with Hodgkin's disease or non-Hodgkin's lymphoma.

Radionuclide evaluation of patients with lymphoma

Nuclear medicine imaging techniques allow us to peer into physiologic processes, avoiding the need to wait until anatomic changes are detectable, and allowing for prompt, informed management decisions. Recognition of normal, abnormal, and post-therapy scan patterns is critical to achieve the necessary sensitivity and specificity needed for patient management. Gallium scintigraphy using updated techniques has an important continuing role in management of patients with lymphoma. Gallium scintigraphy can contribute to patient management primarily by detecting residual disease or relapse after treatment, monitoring response during therapy, and providing prognostic information. FDG and PET cameras, especially dedicated ring systems, offer high resolution and high-contrast images, thereby demonstrating additional sites of disease. Although preliminary evidence looks promising that FDG can provide all information that Ga-67 has been shown to do in the past, additional data are required. Further studies will show whether FDG-PET can provide prognostic information and predict disease-free and overall survival, the availability of both FDG and PET scanners, and issues of cost. Patient accessibility will undoubtedly also play a role in when, or whether, FDG-PET will totally replace Ga-67 scintigraphy in the management of patients with lymphoma.

Thoracoscopy or CT-guided biopsy for residual intrathoracic masses after treatment of lymphoma

BACKGROUND

An intrathoracic mass persists after completion of treatment in 20% of the patients treated for Hodgkin's disease (HD) or non-Hodgkin's lymphoma (NHL). Gallium scan and positron emission tomography allow for diagnosis in most cases. However, in some patients, a pathologic examination of the residual mass (RM) is required. The aim of this study was to evaluate the results of a thoracoscopic approach for intrathoracic RM, as compared with image-guided biopsies.

PATIENTS AND METHODS

From 1996 to 1998, 29 consecutive patients treated for NLH (n = 11) or HD (n = 18) were referred either to radiology (group R; n = 8) or to surgery (group S; n = 21) for biopsy of an intrathoracic RM. There were 13 male and 16 female patients ranging in age from 15 to 56 years (mean, 32 years). The reason for a biopsy was the inability to determine the nature of the RM by means of radiologic examination or scintigraphy. Biopsy was defined as successful when (1) residual lymphoma was found in the specimen, or (2) benign tissue was found and the patient remained disease-free after a minimal follow-up period of 12 months. A biopsy was defined as a failure when a local recurrence occurred in a patient with a diagnosis of benign lesion.

RESULTS

No significant procedure-related complications occurred in either group. The mean follow-up was 26 months (range, 13 to 72 months). In group R, residual lymphoma was found in only one patient. In group S, residual lymphoma was found in seven patients (p = 0.5). In the seven patients of group R with a diagnosis of benign mediastinal lesion, two patients had a local recurrence and one had a recurrence within the abdomen. In the 15 patients of group S in whom no residual disease was found, 1 patient had an intrathoracic recurrence (p = 0.5) while 2 patients had recurrence in a remote site.

CONCLUSION

Despite the limited number of patients in this series, results suggest that a thoracoscopic approach yields better data than image-guided biopsies.

The value of Ga-67 scintigraphy and F-18 fluorodeoxyglucose positron emission tomography in staging and monitoring the response of lymphoma to treatment

Gallium-67 scintigraphy (GS) has the ability to provide important diagnostic and prognostic information for the evaluation of patients with lymphoma. GS is superior to morphologic imaging techniques because of its affinity to viable lymphoma cells. The value of GS lies not in the initial diagnosis but primarily in assessing the results of treatment and in the follow-up of patients with lymphoma. Nevertheless, GS has not gained the expected wide acceptance, possibly because of the meticulous technique required and the expertise needed for optimal interpretation. The introduction of positron emission tomography (PET) with F-18 fluorodeoxyglucose (FDG) as a tumor-seeking agent, which provides images of superior quality, may have an impact on the current role of GS in the management of patients with lymphoma. FDG-PET seems to share with GS the advantages of a tumor viability agent. It appears to be more sensitive for detecting nodal and extranodal sites of disease than GS and may have predictive value during and after therapy for lymphoma. These potential clinical and economic advantages of FDG-PET need to be confirmed in systematic, large-scale prospective studies.

Follicular lymphomas--a review of treatment modalities

Follicular lymphoma is the most common low-grade non Hodgkin's lymphoma and represent an homogeneous entity as defined by pathological, molecular and clinical data. This indolent disease is characterised by a slow growth pattern with possible spontaneous regression, is often disseminated but remains incurable with available treatments when disseminated. For localised stages, involved field radiotherapy remains the standard choice but other approaches remain to be investigated. In advanced disease, chemotherapy has been demonstrated to produce high response rates but recent trials with new treatment strategies including interferon and monoclonal antibodies may improve the current situation. In this article, we will review treatment of follicular lymphomas, specially emphasising published phase III trials.

Positron emission tomography in lymphoma: comparison with computed tomography and Gallium-67 single photon emission computed tomography

With the advent of positron emission tomography (PET), metabolic imaging has become a reality for tumor staging and monitoring response to therapy in lymphoma. Increased Fluorine-18 fluorodeoxyglucose ([(18)F]FDG) uptake in lymphomas has been well documented in the literature; it is based upon elevated glycolysis and longer residence time of FDG in malignant cells compared to most normal tissues. This suggests that in tumor staging, FDG-PET may be more sensitive and specific than the anatomic imaging modalities. Computed tomography (CT) is the standard imaging modality for the staging and restaging of lymphoma, and Gallium-67 ((67)Ga) scintigraphy has played an important role in monitoring response to therapy and follow-up of patients. Published results suggest that FDG-PET is superior to (67)Ga imaging and may be equal or superior to CT for the detection of nodal as well as extranodal involvement in lymphoma.

Prognostic value of thoracic FDG PET imaging after treatment for non-small cell lung cancer

OBJECTIVE

We determined the prognostic value of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) for patients with treated lung cancer.

MATERIALS AND METHODS

We examined patients who underwent FDG PET after first-line treatment for non-small cell lung cancer. FDG PET results were correlated with survival rates to determine whether FDG PET findings were predictive of outcomes.

RESULTS

After initial therapy, 113 patients with non-small cell lung cancer underwent FDG PET. One hundred patients had positive FDG PET results and a median survival of 12 months (95% confidence interval, 9.2-15.4). Thirteen patients had negative FDG PET results, and 11 (85%) of these patients are still living at a median follow-up of 34 months. The difference in survival for patients with positive and negative FDG PET results was statistically significant (p = 0.002).

CONCLUSION

FDG PET has prognostic value and strongly correlates with survival rates of patients with treated lung cancer. Patients with positive FDG PET results have a significantly worse prognosis than patients with negative results. Additionally, FDG PET may be helpful in guiding therapeutic treatments.

Progress in medical imaging of lymphoma and Hodgkin's disease

Noninvasive imaging methods are the cornerstone of the conventional staging of patients with Hodgkin's disease and non-Hodgkin's lymphoma. Gallium-67 scintigraphy has become an important and essential imaging method, especially in the restaging for assessment of residual masses in patients with lymphoma. Magnetic resonance imaging will be used in the future for confirmation of suspect local lesions. Imaging of lymphoma patients with somatostatin receptor scintigraphy will remain a secondary imaging method, which will not be as routine. Positron emission tomography with 18-F-fluorodeoxyglucose (FDG) has made the greatest steps forward and offers, when whole-body FDG-PET is used, the advantage that the entire body of the patient can be imaged. Nodal, extranodal, and bone marrow involvement have been imaged by FDG-PET with great sensitivity and specificity. Perhaps in the future, staging laparotomy for exact staging of lymphoma patients will be unnecessary, and patients will be staged solely with noninvasive staging methods.

Gallium-67 scintigraphy in the management: Hodgkin's disease and non-Hodgkin's lymphoma

Gallium scintigraphy has an important role in the management of patients with lymphoma. It contributes to patient management by detecting residual disease or relapse after treatment, monitoring response during therapy, and providing prognostic information.