FDG PET-CT Findings Research Articles

Endometrial Cancer with Cervical Extension Mimicking Dual Concordant Endometrial and Cervical Malignancy by F-18 FDG PET and MRI

A 35-year-old woman with endometrial cancer and cervical extension underwent F-18 FDG PET-CT [1–6] and MRI studies after resection of a cervical mass presumed to be cervical myoma. The patient underwent cervical myomectomy and the histopathologic report revealed poorly differentiated invasive carcinoma. Cervical cancer was ruled out because the patient had no history of sexual intercourse and was negative for human papilloma virus infection. The patient underwent radical hysterectomy, bilateral salpingo-oophorectomy, pelvic and para-aortic lymph node dissection, and multiple biopsies. F-18 FDG PET-CT (Fig. 1a–e) showed intense FDG uptake along the cervix wall. T2-weighted MRI (Fig. 1f, g) also revealed a mass lesion with high SI involving the anterior and posterior lips of the uterine cervix. Another area of focal increased uptake above the endometrial lesion in the left pelvic cavity was observed on PET-CT and MRI, possibly due to a functioning ovary. PET-CT and MRI were interpreted as showing a dual concordant malignant lesion due to separated FDG uptakes and high SI without any connection between the cervical and endometrial lesions. Fig. 1 F-18 FDG PET-CT (a–e) shows intense FDG uptake along the cervix wall. T2-weighted MRI (f, g) reveals a mass lesion with high SI involving the anterior and posterior lips of the uterine cervix. Together, these images were interpreted as showing ... F-18 FDG PET-CT (Fig. 2a–e) showed intense FDG uptake along the endometrium. Given the patient’s history and the fact that she was not menstruating at the time of imaging, this intense uptake was interpreted as another pathologic lesion, suggesting dual primary lesions. A suspected heterogeneous mass lesion along the endometrium suggesting concordant endometrial cancer was found on MRI (Fig. 2f, g). Endometrial cancer with cervical extension is sometimes difficult to differentiate from primary cervical cancer. Fig. 2 F-18 FDG PET-CT (a–e) shows intense FDG uptake along the endometrium. MRI (f, g) shows a suspected heterogeneous mass lesion along the endometrium suggesting concordant endometrial cancer The final histopathologic report showed poorly differentiated endometrial adenocarcinoma with cervical extension, although the FDG PET-CT and MRI findings were suggestive of concordant cervical and endometrial cancer. Although histopathologic confirmation is necessary for final diagnosis, MRI and FDG PET-CT studies may aid in the differential diagnosis. A metastatic cervical mass from endometrial cancer clinically presenting as cervical myoma is rare. This case suggests that poorly differentiated endometrial cancer may extend into the cervix, presenting as cervical myoma, and the possibility of a metastatic mass should be considered in the differential diagnosis when dealing with cervical myoma.

FDG PET-CT in breast cancer: A single institution experience from India.

e11027 Background: Whole body FDG PET CT is a useful tool in diagnosis, staging and prognosis; and its timely use is critical for early intervention and achieving long term survival in patients with early and advanced breast cancer. Methods: In this observational retrospective study, we report FDG PET CT findings of all breast cancer patients enrolled in our hospital based cancer registry between the years 2008 to 2011. Results: One thousand and fifty three women underwent a total of 1638 scans. Two hundred and forty five scans (14.96%) were done for staging /restaging/diagnosis, 1208 (73.75%) were for response evaluation to chemotherapy and 185 (11.29%) were for surveillance. The median age at diagnosis was 53 years. We identified a possible synchronous breast primary in 28 (2.66%) women and a probable new or existing second non-breast primary in 21(1.99%) women. Internal nodal metastasis was identified in 76 (7.21%) women at diagnosis. There were 26 (2.47%) patients with multicentric tumors. There was an increased uptake in the thyroid gland in 49(2.99%) and in the adrenal in 41 (2.50%) women. There were other random ‘Incidental findings of concern’ in 7 (0.37%) of women, diagnosed either on the CT or PET-CT component. Findings on PET-CT, including- upstaging of the breast primary and unexpected new findings, unrelated to the breast primary, changed the treatment plan in approximately 7% -10% of the patients. We did find that PET-CT did not impact early tumors; however, it did contribute in, 1) the assessment of internal mammary nodes, 2) prognostication based on tumor burden and, 3) aggressive management of oligometastases. Conclusions: Whole body FDG PET CT is a useful tool for staging and prognostication in breast cancer patients. However, the timing of such scans for surveillance needs to be defined for early detection of progression to have an impact on survival.

The role of FDG PET-CT in differential diagnosis of pleural pathologies

ObjectiveThis study has aimed to evaluate the impact of F18 Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography (FDG PET-CT) in the differential diagnosis of malignant and benign pleural lesions in patients with suspected malignant pleural mesothelioma (MPM). Material and methodsFifty patients (32 females, 18 males; age range 24–79 years) with pleural thickening, fluid, plaques or calcification on previous CT scan were examined with FDG PET-CT. PET-CT imaging was obtained 1h after FDG injection. In 12 patients, delayed imaging from the thoracic region was performed 2h after injection. FDG uptake was evaluated visually and semiquantitively using standardized uptake value (SUV). FDG PET-CT findings were compared with histopathologic diagnosis. ResultsThirty-nine patients had increased FDG uptake in pleural lesions but PET-CT results were negative in 11 patients. When compared with histopathological results in FDG positive group, 34 patients had MPM, 5 had benign pathology; in FDG negative group 8 patients had benign pathology, 3 had MPM. Of patients with delayed imaging, 9 showed increased SUV but 3 had a decreased SUV on delayed images. Increased SUV group had 4 MPM, 5 benign pathology (3 chronic granulomatous inflammation, 2 benign asbestotic plaque). Decreased SUV group all had benign pathology (fibrosis, chronic inflammation, myofibrosis). DiscussionFDG PET-CT is a useful imaging modality in differential diagnosis of malignant and benign pleural lesions. Delayed imaging seems to be useful if there is a decrease in SUV suggesting a benign pathology but does not seem to contribute to the differential diagnosis if the SUV is increased.

Response and survival in oesophageal cancer patients following neoadjuvant chemotherapy assessed by FDG-PETCT imaging and corelation to pathologic response.

e14571 Background: Combined positron emission tomography with computed tomography(PETCT) using [18F] 2-fluoro-2-deoxy-D-glucose (FDG) is an important modality for staging oesophageal cancer and may also predict pathological response to chemotherapy. We therefore conducted this retrospective review to assess the relationship between metabolic response measured by FDG-PETCT imaging following neoadjuvant chemotherapy in oesophageal cancer and survival. Methods: Oesophageal cancer patients presenting to Northern Ireland Cancer Centre between January 2003 to December 2008, who had FDG-PETCT assessment for staging and also following neoadjuvant chemotherapy before surgery were included. Routine FDG-PETCT findings were collated and metabolic response (≥ 35% reduction in the tumour standard uptake values[SUV]), evaluated. Pathologic response was assessed and stratified into five histological tumour regression grades (TRG1-5). TRG 1 and 2 groups were classified as pathological responders. Overall survival and event-free survival were obtained. Results: 81 patients with a median age of 66 years (28-77) were identified. 66 (81%) had oesophageal carcinoma and 15 (19%) had Siewart type I or type II oesophageal-gastric junction (OGJ) carcinomas. Metabolic response was identified in 67 (82.3%) of patients. After a median follow up of 25.0 months, the median overall survival in metabolic responders has not been reached. In the metabolic non responders the median overall survival was 15.7 months (p 0.005), (HR = 2.66, 95%CI 1.31-5.41) and median event-free survival was also 15.7 months (p 0.023), (HR = 2.14, 95%CI 1.09-4.21). Pathological response was seen in 14 (17.9%) and this correlates poorly with metabolic response. There is no statistically significant relationship between pathologic response and survival. Conclusions: Metabolic nonresponse to neoadjuvant chemotherapy measured by FDG-PETCT appears to be associated with a poor survival. Further work will seek to identify a molecular signature for lack of response to preoperative chemotherapy in order to minimise exposure of patients to toxic treatment where they are unlikely to benefit. No significant financial relationships to disclose.

F-18 FDG PET-CT Findings in a Case of Normal-Sized Ovarian Cancer Syndrome

The "normal-sized ovary carcinoma syndrome (NOCS)" is defined as a clinical situation, in which diffuse metastatic malignant disease of the abdominal cavity of the female with normal-sized ovaries is noted, but no origin is assigned by preoperative or intraoperative evaluation. We report a case of ovarian serous surface papillary carcinoma with manifestation of NOCS, where F-18 FDG PET/CT scan correctly detected the site of origin, although computed tomography and magnetic resonance imaging failed to detect it. This technique may play a role to discern the site of origin of some malignancies.

F-18 FDG PET-CT Findings in Mikulicz Disease and Systemic Involvement of IgG4-Related Lesions

A 72-year-old woman with Mikulicz disease with pathogically proven sclerosing sialadenitis showed systemic abnormal F-18 FDG uptake in the bilateral lacrimal and submandibular glands, pancreas, abdominal aortic wall, and a retroperitoneal fibroid mass on PET/CT scan, with marked elevation of the serum IgG4 level. This case supports Mikulicz disease being included as 1 of the disorders associated with a new clinical entity of systemic IgG4-related plasmacytic syndrome. A whole-body FDG-PET/CT scan can be expected as a useful tool for detecting systemic involvement in systemic IgG4-related plasmacytic syndrome.

Clinical usefulness of the fluorodeoxyglucose (FDG)-PET maximal standardized uptake value (SUV) in combination with CT features for the differentiation of adenocarcinoma with a bronchioloalveolar carcinoma from other subtypes of non-small cell lung cancers

Purpose To evaluate the clinical usefulness of fluorodeoxyglucose (FDG)-PET maximal SUV in combination with CT features for differentiation of adenocarcinoma with bronchioloalveolar carcinoma (BAC) from other subtypes of non-small cell lung cancer (NSCLC). Materials and methods This retrospective study included 125 patients (104 men and 21 women; mean age, 64 years) who underwent CT and subsequent FDG-PET examinations for preoperative evaluation and underwent curative intent operation with the final diagnoses of NSCLC made by surgical histopathology. We categorized NSCLC into adenocarcinoma with BAC feature and other subtypes. Finally, there were 16 cases of adenocarcinoma with BAC and 109 cases of other NSCLC subtypes included in the study. Several CT features of lung cancer were analyzed, including tumor size, presence of spiculation, margin (irregular or smooth), pattern of the mass (pure solid, pure ground glass opacity and mixed), associated pleural effusion and location (center, mid and periphery). Maximal SUV and visual scores of FDG uptakes of primary NSCLC were evaluated. The diagnostic performances of CT alone, PET alone, and combination of two modalities to predict adenocarcinoma with BAC from other subtypes of NSCLC were calculated. Results A nodule with a mixed pattern with partly solid and ground glass opacity was significantly more frequent CT feature of an adenocarcinoma with BAC (8/16, 50%) as compared with the other subtypes (2/109, 1.8%) ( p < 0.0001). Maximal SUV of adenocarcinoma with BAC (mean = 7.2) was significantly lower than that of other subtypes of NSCLC (mean = 13.33) ( p < 0.0001). Sensitivity, specificity, PPV, and NPV of CT for differentiating adenocarcinoma with BAC from other subtypes was 50% (8/16), 98.2% (107/109), 80% (8/10), and 93% (107/115), respectively. Sensitivity, specificity, PPV, and NPV of FDG-PET was 68.8% (11/16), 86.2% (94/109), 42.3% (11/26), and 94.9% (94/99), respectively. Sensitivity, specificity, PPV, and NPV of combination of two modalities was 81.3% (13/16), 85.3% (93/109), 44.8% (13/29), 96.9% (93/96), respectively. Conclusion Careful combined assessment of the FDG-PET maximal SUV and CT findings have the potential to differentiate an adenocarcinoma with BAC from other NSCLC subtypes, such as a pure BAC. These findings might be useful for imaging interpretations and will help initial planning of NSCLC management.

Sarcomatoid renal cell carcinoma: Rapid dissemination detected on FDG PET‐CT

We present the FDG PET-CT findings in a patient with persistent pain 7 weeks after a nephrectomy and lymph node dissection for a sarcomatoid renal cell carcinoma. Although conventional imaging was unable to detect evidence of metastatic spread outside the para-aortic nodes, a PET-CT scan showed unexpected extensive dissemination. Currently, there are no reports in the literature of the PET-CT findings in sarcomatoid renal cell carcinomas.

FDG PET CT Features of an Intraabdominal Gossypiboma

Retained surgical sponge or gossypiboma in the abdominal cavity is an infrequent but serious surgical complication that may lead to medicolegal problem. The incidence of a surgical sponge retained at operation is difficult to estimate, but it has been reported as 1 in 100 to 3000 for all surgical interventions and 1 in 1000 to 1500 for intraabdominal operations. The natural evolution of a retained sponge, if aseptic, is to cause a foreign body reaction, followed by organization to form a foreign body granuloma, which may mimic a soft tissue neoplasm. Although features of CT and MR imaging of gossypibomas have been documented in the literature, they have often been misinterpreted preoperatively owing to the rarity of gossypibomas in daily clinical practice and to the low index of clinical suspicion. We report the FDG PET CT findings of a 42-year-old woman who had undergone cesarean sections twice previously, with an intraabdominal gossypiboma found incidentally in a routine health examination. We hope the PET CT findings in this case offer us useful adjunctive information to conventional imaging studies in the diagnosis of gossypiboma.