Frequent impact of [18F]fluorodeoxyglucose positron emission tomography on the staging and management of patients with indolent non-Hodgkin's lymphoma

[18F]fluorodeoxyglucose (FDG) positron emission tomography (PET) is useful in staging aggressive non-Hodgkin's lymphoma (NHL). However, its role in indolent NHL has not been established. This retrospective study assessed the sensitivity and clinical impact of PET findings in patients with indolent NHL. Patients with indolent NHL who underwent FDG-PET scanning between May 1997 and August 2001 were identified. Case records were reviewed for FDG-PET and conventional staging/restaging results and compared for concordance. Forty-seven patients were identified. Twelve staging FDG-PET scans and 37 restaging FDG-PET scans were obtained. The FDG-PET case sensitivity rate was 98%. Forty-two percent of staging FDG-PET scans were concordant with conventional staging, with the remaining patients exhibiting more extensive disease on PET. At progression, FDG-PET and conventional assessments were discordant in 46% of cases. Positron emission tomography findings downstaged disease in 30% of these patients and upstaged disease in 16%. Computed tomography (CT) and FDG-PET identified 150 and 146 individual sites of disease, respectively. Among "definite" sites on structural imaging, 74% were also seen on PET. For equivocal lesions, only 19% were seen on both modalities. Clinical management was changed in 34% of patients as a result of FDG-PET findings. Of 22 discordant lesions in which true disease status could be evaluated, the PET findings were confirmed to be correct in 21 (95%; P < 0.0001). These findings demonstrate that FDG-PET has a high sensitivity for indolent NHL and often leads to alteration of disease staging and management. This high accuracy of FDG-PET in assessing discordant lesions suggests a greater diagnostic utility compared with CT.     

Comparison of (18)F Flurodeoxyglucose PET with Ga-67 scintigraphy and conventional imaging modalities in pediatric lymphoma

Flurodeoxyglucose PET (FDG PET) is very useful for staging and restaging adult lymphomas. Its effectiveness in childhood lymphomas is less established. To evaluate the potential utility of FDG PET in the care of pediatric patients with lymphomas, we examined the clinical data and imaging findings of 26 patients, 8 - 19 years of age (14 HD, 12 NHL) who underwent 55 FDG PET studies. Results were compared with CT/MRI and gallium scans. FDG PET provided incremental, clinically important information in 21% of HD cases and 33% of NHL cases. It was especially useful in distinguishing scar tissue from residual disease at the end of therapy. In both HD and NHL, FDG PET had higher sensitivity (94%, 90%) and specificity (100%, 88%) than CT/MRI and gallium scanning. These results indicate that FDG PET is useful in the management of pediatric lymphomas.     

High rates of tumor growth and disease progression detected on serial pretreatment fluorodeoxyglucose‐positron emission tomography/computed tomography scans in radical radiotherapy candidates with nonsmall cell lung cancer

BACKGROUND:

The authors studied growth and progression of untreated nonsmall cell lung cancer (NSCLC) by comparing diagnostic and radiotherapy (RT) planning fluorodeoxyglucose (FDG)‐positron emission tomography (PET)/computed tomography (CT) scans before proposed radical chemo‐RT.

METHODS:

Patients enrolled on a prospective clinical trial were eligible for this analysis if they underwent 2 pretreatment whole body FDG‐PET/CT scans, >7 days apart. Scan 1 was performed for diagnosis/disease staging and scan 2 for RT planning. Interscan comparisons included disease stage, metabolic characteristics, tumor doubling times, and change in treatment intent.

RESULTS:

Eighty‐two patients underwent planning PET/CT scans between October 2004 and February 2007. Of these, 28 patients (61% stage III, 18% stage II) had undergone prior staging PET/CT scans. The median interscan period was 24 days (range, 8‐176 days). Interscan disease progression (TNM stage) was detected in 11 (39%) patients. The probability of upstaging within 24 days was calculated to be 32% (95% confidence interval [CI], 18%‐49%). Treatment intent changed from curative to palliative in 8 (29%) cases, in 7 because of PET. For 17 patients who underwent serial PET/CT scans under standardized conditions, there was a mean relative interscan increase of 19% in tumor maximum standardized uptake value (SUV) (P = .022), 16% in average SUV (P = .004), and 116% in percentage injected dose (P = .002). Estimated doubling time of FDG avid tumor was 66 days (95% CI, 51‐95 days).

CONCLUSIONS:

Rapid tumor progression was detected in patients with untreated, predominantly stage III, NSCLC on serial FDG‐PET/CT imaging, highlighting the need for prompt diagnosis, staging, and initiation of therapy in patients who are candidates for potentially curative therapy. Cancer 2010. © 2010 American Cancer Society.     

Impact of positron emission tomography on the management of patients with small-cell lung cancer: preliminary experience

Accurate staging is important in small-cell lung cancer (SCLC). Patients with limited stage may benefit from chemoradiation, whereas those with extensive stage conventionally receive chemotherapy. Prophylactic cranial irradiation may benefit those attaining complete remission (CR). 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) enhances accuracy of staging in non-SCLC. Its role in SCLC remains unclear. We reviewed 36 consecutive SCLC patients who underwent 47 PET studies between December 1996 and January 2001, for either staging (n = 11), restaging after therapy (n = 21), or both (n = 4). Conventional imaging was also performed. Of 15 patients who had PET for staging, 5 (33%) were upstaged from limited to extensive disease and treated without thoracic radiotherapy. Twenty-five patients underwent 32 restaging PET scans, of which 20 (63%) were discordant with conventional imaging. In 8 cases PET showed more extensive disease than conventional imaging, and in 12 cases PET-apparent disease appeared less extensive. In 13 patients, 14 untreated discordant lesions were evaluable; PET was confirmed accurate in 11 (79%) sites by last follow-up. Restaging PET influenced management in 13 cases (52%). PET-CR conferred longer median time to progression (13.7 months) than no CR (9.7 months). FDG-PET for SCLC was often discordant with conventional assessment and frequently influenced management.     

Rectal cancer staging: An up‐to‐date pictorial review

Colorectal cancer is the third most common malignancy worldwide, and rectal cancer (RC) accounts for 29% of all cases. Local staging of RC is crucial for the purposes of addressing patients appropriately to surgery alone or to preoperative chemoradiotherapy (pCRT) followed by total mesorectal excision (TME). Combined pCRT and TME may negatively affect rectal function, so rectum‐sparing approaches such as transanal local excision have been proposed as an alternative to TME for patients showing a major or complete clinical response on restaging after pCRT. Magnetic resonance imaging (MRI) has a fundamental role in the local staging and restaging of RC, with or without positron emission tomography (PET). PET/MRI enables a multiplanar high‐resolution morphological study of the pelvis, providing important information on cell density and metabolic activity with diffusion‐weighted imaging (DWI) and ¹⁸F fluorodeoxyglucose uptake respectively. This article offers a pictorial review of the MRI anatomy of the ano‐rectal region and an update on local RC staging with a hybrid ¹⁸F‐FDG PET/MRI scan.     

ORIGINAL ARTICLE: Pilot comparison of 18F-fluorocholine and 18F-fluorodeoxyglucose PET/CT with conventional imaging in prostate cancer

Introduction: Conventional imaging (CI) is known to have limitations with respect to staging of patients with primary or relapsed prostate cancer. Positron emission tomography/computed tomography (PET/CT) with ¹⁸F-flurodeoxyglucose (FDG) is also often suboptimal because of low tracer avidity, but ¹⁸F-fluorocholine (FCH) appears to be a promising alternative molecular imaging probe. We report a prospective pilot study of PET/CT comparing both tracers for staging and restaging of patients with prostate cancer. Methods: Sixteen prostate cancer patients were evaluated (7 for staging and 9 for restaging). All patients also underwent CI, comprising at least an abdominopelvic CT and a bone scan. All imaging results and other relevant data were extracted from the imaging reports and medical charts. Results: Based on all imaging-detected disease sites, both FCH-PET/CT and FDG-PET/CT (79%) were more sensitive than CI (14%), with the highest number of sites of nodal and distant disease on FCH PET/CT. FCH-PET/CT alone would have provided sufficient clinical information to form an appropriate management plan in 88% of cases, as compared with 56% for CI. Conclusion: FCH-PET/CT has the potential to impact on the management of patients with prostate cancer significantly more often than CI.     

The utility of body FDG PET in staging primary central nervous system lymphoma

(18)F-Fluorodeoxyglucose (FDG) PET has become an important tool in the management of non-Hodgkin's lymphoma (NHL), but its role in the evaluation of primary CNS lymphoma (PCNSL) has not been established. We investigated the ability of body FDG PET to detect systemic disease in the staging and restaging of PCNSL. The records of 166 PCNSL patients seen at Memorial Sloan-Kettering Cancer Center were examined. Forty-nine patients who underwent body FDG PET for staging of PCNSL were identified. Clinical data were reviewed to determine FDG PET results and their influence on therapy. Body FDG PET disclosed a systemic site of malignancy in 15% of patients. NHL was found in 11% of all patients, 7% of patients at diagnosis, and 27% of patients at CNS relapse. Four percent had a second systemic neoplasm. Workup with conventional staging did not reveal systemic disease, and in 8% of patients, body FDG PET was the only abnormal diagnostic exam suggestive of lymphoma. FDG PET findings altered patient treatment and resulted in additional chemotherapy, surgery, or radiotherapy. Our findings suggest that FDG PET may be more sensitive than conventional body staging and may disclose higher rates of concomitant systemic disease at PCNSL diagnosis. Body FDG PET may be an important noninvasive adjunct to conventional PCNSL staging, and its utility should be evaluated prospectively.     

Clinical impact of (18)F fluorodeoxyglucose positron emission tomography in patients with non-small-cell lung cancer: a prospective study.

PURPOSE: To prospectively study the impact of (18)F fluorodeoxyglucose (FDG) positron emission tomography (PET) on clinical management of patients with non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: One hundred five consecutive patients with NSCLC undergoing (18)F FDG PET were analyzed. Before PET, referring physicians recorded scan indication, conventional clinical stage, and proposed treatment plan. PET scan results were reported in conjunction with available clinical and imaging data, including results of computed tomography (CT). Subsequent management and appropriateness of PET-induced changes were assessed by follow-up for at least 6 months or until the patient's death. RESULTS: Indications for PET were primary staging (n = 59), restaging (n = 34), and suspected malignancy subsequently proven to be NSCLC (n = 12). In 27 (26%) of 105 of cases, PET results led to a change from curative to palliative therapy by upstaging disease extent. Validity of the PET result was established in all but one case. PET appropriately downstaged 10 of 16 patients initially planned for palliative therapy, allowing either potentially curative treatment (four patients) or no treatment (six patients). PET influenced the radiation delivery in 22 (65%) of 34 patients who subsequently received radical radiotherapy. Twelve patients considered probably inoperable on conventional imaging studies were downstaged by PET and underwent potentially curative surgery. PET missed only one primary tumor (5-mm scar carcinoma). CT and PET understaged three of 20 surgical patients (two with N1 lesions < 5 mm and one with unrecognized atrial involvement), and PET missed one small intrapulmonary metastasis apparent on CT. No pathological N2 disease was missed on PET. CONCLUSION: FDG PET scanning changed or influenced management decisions in 70 patients (67%) with NSCLC. Patients were frequently spared unnecessary treatment, and management was more appropriately targeted.     

18F]fluorodeoxyglucose positron emission tomography scanning for staging, response assessment, and disease surveillance in patients with mantle cell lymphoma

BackgroundPositron emission tomography (PET) is an important imaging modality in the staging and response assessment of patients with lymphoma, but data on its specific use in mantle cell lymphoma (MCL) are lacking.Patients and MethodsThe records of 28 patients with MCL who had a total of 123 [¹⁸F]fluorodeoxyglucose (FDG) PET scans between March 1999 and November 2005 were reviewed. Nine patients had staging scans. The other scans were performed for response assessment or relapse surveillance.ResultsFDG-PET sensitivity was 100% for nodal disease in the 9 patients studied at baseline. Positron emission tomography scans performed for response assessment were concordant with conventional imaging in 47% and discordant in 53% of cases. Positron emission tomography scanning led to earlier diagnosis of relapse in 1 of 17 patients but produced a high rate of false-negative findings in the evaluation of gastrointestinal involvement.ConclusionFDG-PET appears to be a sensitive modality for staging and for response assessment in MCL but was not found to be useful in relapse surveillance or in the evaluation of gastrointestinal disease.     

PET imaging for suspected residual tumour or thoracic recurrence of non-small cell lung cancer after pneumonectomy

F-18 fluorodeoxyglucose-positron emission tomography (PET) was investigated in patients with suspected residual disease or intrathoracic recurrence after pneumonectomy. Patients were identified from a prospective database. Impact of PET on staging and patient management was assessed. Clinical outcome was used to assess appropriateness of management. PET was performed in 17 cases, either post-operatively (n = 8), or later for suspected recurrence (n = 9) in patients with good performance status and without extensive disease on conventional imaging. PET changed treatment in 10 cases (59%). In five patients (29%), PET changed treatment intent (curative versus non-curative) from radical radiotherapy (RT) to palliative RT (n = 1), or observation or supportive care (n = 3), or from palliative to radical RT (n = 1). In a further patient with unexplained pain, PET appropriately showed no evidence of disease. In additional five cases (29%), PET influenced choice of RT dose and the use of concurrent chemotherapy (n = 3) or target volume (n = 2). Patients without tumour or with limited disease on PET had favourable outcomes whereas those with extensive disease suffered early tumour progression. PET was discordant with conventional assessment in >50% of cases. PET may be valuable after pneumonectomy if the patient is being considered for adjuvant or salvage radiotherapy although specificity may be reduced due to post-operative inflammatory changes.     

[18F]FDG PET/CT and PET/MR in Patients with Adrenal Lymphoma: A Systematic Review of Literature and a Collection of Cases

Aim. The present study aimed to assess the existing data about Primary Adrenal Lymphoma (PAL) evaluated with FDG PET and to describe a small monocentric series of cases. A systematic analysis (from 2010 to 2022) was made by using PubMed and Web of Science databases reporting data about the role of FDG PET/CT in patients with suspicious or known adrenal lymphoma. The quality of the papers was assessed by using QUADAS-2 criteria. Moreover, from a single institutional collection between 2010 and 2021, data from patients affected by adrenal lymphoma and undergoing contrast-enhanced compute tomography (ceCT)/magnetic resonance (MR) and FDG PET/CT or PET/MR were retrieved and singularly described. Seventy-eight papers were available from PubMed and 25 from Web of Science. Forty-seven (Nr. 47) Patients were studied, most of them in the initial staging of disease (n = 42; 90%). Only in one paper, the scan was made before and after therapy. The selected clinical cases were relative to the initial staging of disease, the restaging, and the evaluation of response to therapy. PET/CT and PET/MR always showed a high FDG uptake in the primary adrenal lesions and in metastatic sites. Moreover, PET metrics, such as maximum standardized uptake value (SUVmax) and metabolic tumor volume (MTV), were elevated in all primary adrenal lesions. In conclusions, FDG PET either coupled with CT or MRI can be useful in staging, restaging, and for the evaluation of treatment response in patients affected by PAL     

^18F-FDG PET/CT在结直肠癌诊断和治疗中的价值

结直肠癌在我国是常见的恶性肿瘤,发病率逐年上升,但近30年的治疗效果进步不大,因而,术前早期正确的诊断和分期、术后检测复发转移以及判断治疗效果,对于个体化的治疗意义重大.集解剖和功能显像优势于一身的^18F-FDG PET/CT显像在结直肠癌诊断和治疗上具有广泛的应用前景和价值.大多数结直肠癌病变在PET上表现为高度的浓聚灶,^18F-FDG PET/CT对于结直肠原发灶诊断准确率一般在92.7%～95%之间,其敏感度高,假阴性率低.18F-FDG PET/CT可以早期发现转移病灶,是目前最好的术前分期手段;对结直肠癌复发及转移诊断的灵敏度、特异性及准确性分别为89%～94.6%、83.3%～100%、90%～98.3%,显著优于传统的检查方式,可以发现更多微小或隐匿的复发和转移灶.此外,PET/CT可以通过病灶代谢的变化先于超声、CT、MRI等形态学手段早期判定化疗效果,指导临床及时更改治疗方案以及进行术前再分期.总之,PET/CT为结直肠癌的诊断、术前分期、监测术后复发转移、评估疗效提供了一种安全无创的功能影像方法.     

Retrospective review of extra-pulmonary small cell carcinoma and prognostic factors

Background

Extra-pulmonary small cell carcinoma (EPSCC) is a rare cause of malignancy, representing 2.5–5 % of all small cell carcinomas, with an incidence rate of 1000 cases per year in the USA. The purpose of this study is to characterize the location, extent of disease, and survival of patients with EPSCC, and to analyze potential clinical prognostic indicators predicting survival.

Methods

A retrospective review of all patients with EPSCC between the years 2000 and 2010 was conducted. Patients included for analysis had pathologic diagnosis of EPSCC, poorly differentiated tumors, and negative chest imaging at diagnosis.

Results

53 patients were included in the analysis. 23 patients (43 %) had limited disease (LD) at diagnosis, and 30 patients (57 %) had extensive disease (ED) at diagnosis. Carcinoma of unknown primary represented the largest proportion of patients (40 %), followed by genitourinary (26 %), gastrointestinal (15 %), head and neck (11 %), gynecologic (6 %), and breast (2 %). The median overall survival (OS) was 4.7 months; 14.5 months for LD, and 3.7 months for ED. Genitourinary EPSCC had the best median OS at 13.1 months, and GI carcinomas had the worst at 1.7 months. On univariate analysis, ED (p = 0.0001), non-genitourinary EPSCC (p = 0.036), and hyponatremia were associated with worse OS (p = 0.0176).

Conclusions

In a cohort of patients with EPSCC, hyponatremia, non-genitourinary EPSCC, and extensive disease were associated with worse OS. Anatomic site predicted survival, which suggests that pathologic heterogeneity between individual tumor sites, including mixed tumor pathology, may affect the prognosis of this rare disease. Future directions for research should include thorough pathologic and genetic profiles.     

PET scanning in lung cancer: current status and future directions

Positron emission tomography (PET) represents a dramatic advance in the imaging of lung cancer. It is valuable for the diagnosis, staging, prognosis, and restaging of disease, and is most useful in patients considered for potentially curative therapy for non-small-cell lung cancer (NSCLC). In this work the current status and potential future applications of PET scanning in lung cancer are discussed. The relevant literature is also discussed, with an emphasis on studies with clinical applicability. Most of these studies involved the use of 18F-fluorodeoxyglucose (FDG). Numerous studies of the use of PET to assess undiagnosed pulmonary nodules have reported significant improvements in accurate diagnosis or exclusion of malignancy compared to conventional structural imaging alone. All of these studies, including metaanalysis, have shown that PET is more accurate than CT-based structural imaging in staging the mediastinum in surgical candidates. PET may have value in radiotherapy planning, and PET-based staging more accurately predicts survival in radiotherapy-treated patients than conventional staging. The rate of unsuspected distant metastasis detection in stage III disease exceeds 20%. PET also facilitates an accurate assessment of response in patients treated with radical chemoradiation or neoadjuvant therapy prior to surgery. PET has rapidly become an indispensable part of the evaluation of patients with potentially curable lung cancer; however, more work is required to define its role.     

F-18 fluorodeoxyglucose positron emission tomography staging in radical radiotherapy candidates with nonsmall cell lung carcinoma: powerful correlation with survival and high impact on treatment

BACKGROUND: Successful treatment of nonsmall cell lung carcinoma (NSCLC) with radical radiotherapy (RT) requires accurate delineation of tumor extent. Conventional computed tomography-based noninvasive staging often estimates intrathoracic thoracic tumor extent incorrectly and fails to detect distant metastasis. High sensitivity and specificity are reported for F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) staging in potentially resectable NSCLC. The authors investigated FDG-PET staging in radical RT candidates with unresectable NSCLC. METHODS: The authors prospectively studied 153 consecutive patients with unresectable NSCLC who were candidates for radical RT after conventional staging and had PET scans. Patients were allocated both "before PET" and "after PET" stages. Subsequent management was recorded. Survival analysis was used to compare validity of pre-PET and post-PET staging. RESULTS: After PET, 107 patients (70%) actually received radical therapies (radical RT with or without concurrent chemotherapy, n = 102; radical surgery, n = 5); 46 patients (30%) received palliative treatment because of PET-detected distant metastasis (n = 28; 18%) or extensive locoregional disease (n = 18; 12%). Palliative therapies were RT (n = 33), chemotherapy (n = 12), or supportive care (n = 1). All five surgically treated patients underwent potentially curative resections after downstaging by PET. For radically treated patients, post-PET stage (P = 0.0041) but not pre-PET stage (P = 0.19) was strongly associated with survival. Radically treated patients survived longer than those treated palliatively (P = 0.02; 1-year survival, 69% and 44%, respectively; 2-year survival, 44% radical; no palliative patients had 2-yr follow-up). CONCLUSIONS: Positron emission tomography-assisted staging detected unsuspected metastasis in 20%, strongly influenced choice of treatment strategy, frequently impacted RT planning, and was a powerful predictor of survival. Potential impact of FDG-PET is even greater in radical RT candidates with NSCLC than in surgical candidates.     

18fluorodeoxyglucose positron emission tomography to detect mediastinal or internal mammary metastases in breast cancer.

PURPOSE: To determine the prevalence of suspected disease in the mediastinum and internal mammary (IM) node chain by 18fluorodeoxyglucose (FDG) positron emission tomography (PET), compared with conventional staging by computed tomography (CT) in patients with recurrent or metastatic breast cancer. PATIENTS AND METHODS: We retrospectively evaluated intrathoracic lymph nodes using FDG PET and CT data in 73 consecutive patients with recurrent or metastatic breast cancer who had both CT and FDG PET within 30 days of each other. In reviews of CT scans, mediastinal nodes measuring 1 cm or greater in the short axis were considered positive. PET was considered positive when there were one or more mediastinal foci of FDG uptake greater than the mediastinal blood pool. RESULTS: Overall, 40% of patients had abnormal mediastinal or IM FDG uptake consistent with metastases, compared with 23% of patients who had suspiciously enlarged mediastinal or IM nodes by CT. Both FDG PET and CT were positive in 22%. In the subset of 33 patients with assessable follow-up by CT or biopsy, the sensitivity, specificity, and accuracy for nodal disease was 85%, 90%, and 88%, respectively, by FDG PET; 54%, 85%, and 73%, respectively, by prospective interpretation of CT; and 50%, 83%, and 70%, respectively, by blinded observer interpretation of CT. Among patients suspected of having only locoregional disease recurrence (n = 33), 10 had unsuspected mediastinal or IM disease by FDG PET. CONCLUSION: FDG PET may uncover disease in these nodal regions not recognized by conventional staging methods. Future prospective studies using histopathology for confirmation are needed to validate the preliminary findings of this retrospective study.     

Restaging of recurrent cervical carcinoma with dual-phase [18F]fluoro-2-deoxy-D-glucose positron emission tomography

BACKGROUND: The clinical value of positron emission tomography (PET) with [18F]fluoro-2-deoxy-D-glucose (FDG) for primary staging in cervical carcinoma appears to be promising. The authors sought to evaluate the diagnostic efficacy and benefit of PET in restaging cervical carcinoma at the time of first recurrence. METHODS: Forty patients with cervical carcinoma who experienced confirmed treatment failure but who were feasible candidates for curative salvage therapy were enrolled prospectively in the current study. Restaging was performed with PET and with computed tomography and/or magnetic resonance imaging (CT/MRI). Dual-phase PET was performed by adding 3-hour-delayed images to the 40-minute scans. The results of the PET and CT/MRI scans were compared. Lesion status was determined by pathologic findings or by clinical follow-up. The receiver operating characteristic curve method with calculation of area under the curve (AUC) was used to evaluate diagnostic efficacy. The primary endpoint was percent improvement in restaging (with improvement indicated by treatment modification) after PET. The secondary endpoint was 2-year overall survival among study participants compared with comparable previously treated patients who did not undergo disease restaging with PET. RESULTS: Twenty-two patients (55%) had their treatment modified due to PET findings. PET was significantly superior to CT/MRI (sensitivity: 92% vs. 60%; AUC: 0.962 vs. 0.771; P<0.0001) in identifying metastatic lesions. For individuals receiving primary surgery, a significantly better 2-year overall survival rate was observed among study participants compared with patients who underwent disease restaging without PET (HR, 0.21 [95% confidence interval, 0.05-0.83]; P=0.020). CONCLUSIONS: Dual-phase FDG-PET is superior to CT/MRI in the restaging of recurrent cervical carcinoma. Restaging with PET provides benefit by allowing the physician to offer optimal management of recurrent cervical carcinoma.     

Imaging with F‐18 FDG PET is superior to Tl‐201 SPECT in the staging of non‐small cell lung cancer for radical radiation therapy*

Thallium‐201 (Tl‐201) single photon emission computed tomography (SPECT) is funded for evaluation of malignancy in Australia and may have utility for staging of non‐small cell lung cancer (NSCLC) if CT results are equivocal. Fluorine‐18 fluorodeoxyglucose (F‐18 FDG) positron emission tomography (PET) is superior to CT for staging NSCLC but is more expensive and less widely available than Tl‐201 SPECT. Therefore, these techniques were prospectively compared in 27 radical radiation therapy candidates. Patients were allocated a conventional, PET and Tl‐201 stage. Tumour to background ratios (TBR) were recorded for the primary on both techniques. Metastatic disease was confirmed by surgical pathology, serial imaging or clinical follow up. Tumour to background ratios were consistently higher for FDG PET than Tl‐201 SPECT (P < 0.0001). Positron emission tomography detected all known primary tumours but Tl‐201 failed to image four primary tumours (15%). In 10 of 18 cases of discordance between PET and Tl‐201 SPECT regarding stage, corroboration was available from pathology or disease progression. Positron emission tomography was shown to have a 100% positive predictive value, including all three patients with PET‐detected distant metastases (P = 0.002). Results indicate that PET is superior to Tl‐201 SPECT scanning in the staging of NSCLC for radical radiation therapy, and that the low sensitivity for detection of local and metastatic disease is likely to limit the clinical impact and cost‐effectiveness of this technique despite its lower cost.     

Effect on prognosis of bone marrow infiltration detected by magnetic resonance imaging in small cell lung cancer

The staging system of limited disease (LD) and extensive disease (ED) is widely used and has been shown to provide useful prognostic information in cases of small cell lung cancer (SCLC). However, accurate examinations are necessary for correct staging. In this report, we evaluated the clinical usefulness of magnetic resonance imaging (MRI) of bone marrow in SCLC. 37 patients with LD by standard staging and 41 with ED were examined with bone marrow MRI. Results of bone marrow MRI did not influence the choice of treatment in patients with LD. For subsequent analysis, patients with LD were divided into two groups: patients in whom bone marrow infiltration was detected with MRI (MRI-positive LD group) and those in whom it was not (MRI-negative LD group). Focal or diffuse metastases to bone marrow were detected with MRI in 46% (36/78) of all patients and 35% (13/37) of LD patients. The response rates to treatment in patients with MRI-positive LD were lower than those in patients with MRI-negative LD (P=0.006). The survival of patients with MRI-positive LD was worse than that of MRI-negative LD (generalised Wilcoxon test: P=0.0157), and closer to that of ED. Multivariate analyses using a Cox model that included the result of bone marrow MRI, performance status, chemotherapy regimen, radiotherapy and serum lactose dehydrogenase (LDH) level showed that the result of bone marrow MRI remained a prognostic factor in SCLC patients with limited disease. Bone marrow examination with MRI is useful for better staging of SCLC. According to our analysis of response rates and survival, MRI-positive LD should be considered a type of ED.     

The role of FDG PET/CT in patients with locoregional breast cancer recurrence: A comparison to conventional imaging techniques

Purpose

The aim of this study was to evaluate the impact of ¹⁸F-fluorodeoxyglucose positron-emission tomography/computed tomography (FDG PET/CT) on clinical management in patients with locoregional breast cancer recurrence amenable for locoregional treatment and to compare the PET/CT results with the conventional imaging data.

Patients and methods

From January 2006 to August 2008, all patients with locoregional breast cancer recurrence underwent whole-body PET/CT. PET/CT findings were compared with results of the conventional imaging techniques and final pathology. The impact of PET/CT results on clinical management was evaluated based on clinical decisions obtained from patient files.

Results

56 patients were included. In 32 patients (57%) PET/CT revealed additional tumour localisations. Distant metastases were detected in 11 patients on conventional imaging and in 23 patients on PET/CT images (p < 0.01). In 25 patients (45%), PET/CT detected additional lesions not visible on conventional imaging. PET/CT had an impact on clinical management in 27 patients (48%) by detecting more extensive locoregional disease or distant metastases. In 20 patients (36%) extensive surgery was prevented and treatment was changed to palliative treatment. The sensitivity, specificity, accuracy, positive and negative predictive values of FDG PET/CT were respectively 97%, 92%, 95%, 94% and 96%.

Conclusions

PET/CT, in addition to conventional imaging techniques, plays an important role in staging patients with locoregional breast cancer recurrence since its result changed the clinical management in almost half of the patients. PET/CT could potentially replace conventional staging imaging in patients with a locoregional breast cancer recurrence.