Standardized FDG uptake as a prognostic variable and as a predictor of incomplete cytoreduction in primary advanced ovarian cancer

INTRODUCTION

In patients with advanced ovarian cancer undergoing preoperative PET/CT, we investigated the prognostic value of SUV in the primary tumor and we evaluated the value of SUV for predicting incomplete primary cytoreduction (macroscopic residual tumor).

MATERIAL AND METHODS

From September 2004 to August 2007, 201 consecutive patients with a pelvic tumor and a Risk of Malignancy Index (RMI) > 150 based on serum CA-125, ultrasound examinations and menopausal state, underwent PET/CT within two weeks prior to standard surgery/debulking of a pelvic tumor. At two-year follow-up (August 15, 2009) the association between SUV and overall survival/cytoreductive result were analyzed in 60 ovarian cancer patients (58 stage III and two stage IV).

RESULTS

At inclusion median age was 62 years (range 35-85 years); 97% (58/60) had a performance status ≤2; 42% (25/60) underwent complete debulking (no macroscopic residual tumor); median SUV(max) was 13.5 (range 2.5-39.0). Median follow-up was 30.2 months. At follow-up 57% (34/60) were alive and 43% (26/60) had died from ovarian cancer. SUV(max) in patients alive was not statistically different from SUV(max) in dead patients (p=0.69), and SUV(max) was not correlated with the amount of residual tumor after surgery (p=0.19). Using univariate Cox regression analysis, residual tumor was a significant prognostic variable (p=0.001); SUV(max) was not a statistically significant prognostic variable (p=0.86).

DISCUSSION

FDG uptake (SUV(max)) in the primary tumor of patients with advanced ovarian cancer was not a prognostic variable and the FDG uptake did not predict complete cytoreduction after primary surgery. Future prospective clinical trials will need to clarify if other PET tracers can serve as prognostic variables in ovarian cancer.

Intraoperative 3-dimensional ultrasound for resection control during brain tumour removal: preliminary results of a prospective randomized study

INTRODUCTION

The amount of resection is closely related to survival in brain tumours. To enhance resection, especially intraoperative magnetic resonance imaging (MRI) has been applied. The aim of this prospective, randomized study was to test if intraoperative 3-D ultrasound likewise can be used for resection control.

METHODS

16 patients, who underwent surgery for intraaxial tumours in non-eloquent brain areas, were initially included into this prospective study. In two patients, the small size of the craniotomy hindered intraoperative ultrasound imaging. In 14 patients, 3-D ultrasound images were obtained before and after opening of the dura, during tumour removal, prior to evaluation by a blinded investigator for identification of tumour remnants, and after dura closure. Seven patients were randomized to complete tumour removal according to the impression of the surgeon (group 1). Seven patients were randomized to incomplete tumour removal (tumour remnant <1cm) (group 2); in these patients, the neurosurgeon intentionally left a tumour remnant prior to evaluation by the blinded investigator. The tumour remnant was then removed. It was tested if 3-D ultrasound can correctly identify complete and incomplete tumour resection. All patients underwent early postoperative MRI.

RESULTS

In two patients (one each of the two groups) the image quality was too poor for a meaningful intraoperative evaluation. In the six patients randomized for incomplete tumour removal, 3-D ultrasound correctly identified tumour remnants in four patients (67%). In six patients randomized for complete tumour removal, 3-D ultrasound confirmed complete tumour resection in three patients. In addition, 3-D ultrasound identified correctly one tumour remnant in a patient randomized for complete tumour removal. Thus, the sensitivity for tumour remnant detection increased to 71% (five of seven patients) and that of confirmation of complete tumour removal was 60 % (three of five patients).

CONCLUSION

The number of investigated patients is still to low to allow definite conclusions. However, the study results suggest, that 3-D ultrasound is especially helpful for detection of overseen brain tumour tissue.

The value of postoperative/preadjuvant chemotherapy computed tomography in the management of patients with ovarian cancer

OBJECTIVE

The objectives of the study were to compare the operative assessment of residual disease with the postoperative computed tomography (CT) findings in patients with ovarian cancer who underwent primary surgical cytoreduction or interval debulking surgery to residual disease 1 cm or less and to assess the effect of potential prognostic factors on patient survival.

METHODS

Patients scheduled for surgery and with an available postoperative CT were eligible for the study. Images were retrospectively analyzed in consensus by 2 radiologists.A 5-point qualitative scoring system was used to evaluate the CT findings (1 = tumor definitely absent, 2 = tumor probably absent, 3 = tumor possibly present, 4 = tumor probably present, 5 = tumor definitely present).

RESULTS

Between September 2005 and December 2008, 206 consecutive patients were enrolled; 51 were eligible. In 30 cases (59%), the postoperative CT findings correlated with the surgeon's assessment of residual disease. For the univariate analyses, the only significant prognostic factors associated with overall survival were no residual disease versus residual disease of less than 1 cm as assessed by the surgeon (hazard ratio [HR], 3.06; 95%confidence interval [CI], 1.29--7.27; P = 0.011) and no residual disease versus residual disease greater than 1 cm on CT (HR, 2.57; 95% CI, 1.02--6.48; P = 0.045). The interaction of surgical residual disease and stage 3 was significant (HR, 3.40; 95% CI, 1.42--8.16;P = 0.006) in the multivariate Cox model.

CONCLUSIONS

There was only 59% correlation between the surgical assessment and post operative CT findings of residual disease in patients reported to have undergone optimal surgery. Stage and residual disease as assessed by the surgeon were significant prognostic factors for overall survival. The value for postoperative CT may lie in those cases with small-volume residual disease (visible but reported as G1 cm) at surgery.

The value of 11C-5-hydroxy-tryptophan positron emission tomography in neuroendocrine tumor diagnosis and management: experience from one center

Many neuroendocrine tumors (NET) are small and may escape localization by conventional imaging techniques. In such cases, 11C-5-hydroxy-tryptophan (11C-5-HTP) positron emission tomography (PET) has been tested as an additional diagnostic tool. Nine patients with clinically, biochemically and/or histologically confirmed NET and negative computerized tomography (CT) or magnetic resonance imaging (MRI), and 111In-pentetreotide (Octreoscan) scintigraphy underwent imaging with 11C-5-HTP-PET/CT in order to: 1) detect the primary tumor lesion in three patients; 2) detect residual disease in two patients with appendiceal carcinoid, one with rectal carcinoid, one with midgut carcinoid, and one with ectopic ACTH secretion (EAS) due to residual pulmonary carcinoid; and 3) restage a patient with medullary thyroid carcinoma (MTC) and hepatic metastases. 11C-5-HTP-PET/CT detected lesions in the mediastinum in a patient with EAS due to a pulmonary carcinoid, further hepatic metastases in a patient with carcinoid syndrome (CS) from a NET of unknown primary, further hepatic metastases in the patient with MTC, and hepatic metastases in the patient with midgut carcinoid. The 11C-5-HTP-PET/CT findings contributed to radical cure of the patient with recurrent EAS, and pointed towards bilateral adrenalectomy in the patient with EAS without evident primary tumor. In addition, 11C-5- HTP-PET/CT directed towards combined surgical and medical treatment in the patient with CS and multiple rather than single hepatic metastases and in the patient with midgut carcinoid, and towards continuation of medical treatment in the patient with MTC. 11C-5-HTP-PET/CT is a useful imaging technique, providing additional information for the diagnosis, staging and decision-making regarding management of patients with NET.

Association of computed tomography morphologic criteria with pathologic response and survival in patients treated with bevacizumab for colorectal liver metastases

CONTEXT

The standard criteria used to evaluate tumor response, the Response Evaluation Criteria in Solid Tumors (RECIST), were developed to assess tumor shrinkage after cytotoxic chemotherapy and may be limited in assessing response to biologic agents, which have a cytostatic mechanism of action.

OBJECTIVE

To validate novel tumor response criteria based on morphologic changes observed on computed tomography (CT) in patients with colorectal liver metastases treated with bevacizumab-containing chemotherapy regimens.

DESIGN, SETTING, AND PATIENTS

A total of 234 colorectal liver metastases were analyzed from 50 patients who underwent hepatic resection after preoperative chemotherapy that included bevacizumab at a comprehensive US cancer center from 2004 to 2007; date of last follow-up was March 2008. All patients underwent routine contrast-enhanced CT at the start and end of preoperative therapy. Three blinded, independent radiologists evaluated images for morphologic response, based on metastases changing from heterogeneous masses with ill-defined margins into homogeneous hypoattenuating lesions with sharp borders. These criteria were validated with a separate cohort of 82 patients with unresectable colorectal liver metastases treated with bevacizumab-containing chemotherapy.

MAIN OUTCOME MEASURES

Response determined using morphologic criteria and RECIST was correlated with pathologic response in resected liver specimens and with patient survival.

RESULTS

Interobserver agreement for scoring morphologic changes was good among 3 radiologists (kappa, 0.68-0.78; 95% confidence interval [CI], 0.51-0.93). In resected tumor specimens, the median (interquartile range [IQR]) percentages of residual tumor cells for optimal morphologic response was 20% (10%-30%); for incomplete response, 50% (30%-60%); and no response, 70% (60%-70%; P < .001). With RECIST, the median (IQR) percentages of residual tumor cells were for partial response 30% (10%-60%); for stable disease, 50% (20%-70%); and for progressive disease, 70% (65%-70%; P = .04). Among patients who underwent hepatic resection, median overall survival was not yet reached with optimal morphologic response and 25 months (95% CI, 20.2-29.8 months) with incomplete or no morphologic response (P = .03). In the validation cohort, patients with optimal morphologic response had median overall survival of 31 months (95% CI, 26.8-35.2 months) compared with 19 months (95% CI, 14.6-23.4 months) with incomplete or no morphologic response (P = .009). RECIST did not correlate with survival in either the surgical or validation cohort.

CONCLUSION

Among patients with colorectal liver metastases treated with bevacizumab-containing chemotherapy, CT-based morphologic criteria had a statistically significant association with pathologic response and overall survival.

An experimental environment for the production, exchange and discussion of fused radiology images, for the management of patients with residual brain tumour disease

The present work aims to display the use of groupware as a tool for better management of the available resources (human, computing and imaging) within the University Hospital of Patras, Greece for the task of managing patients with postoperative residual brain tumour. Emphasis is given to the additional information that can be revealed and taken into account from novel image processing techniques, developed by our group, and the central role of the Medical Physicist in the groupware. Fused images, produced by the combination of CT, MR and SPECT representations of the brain, contain both anatomical and functional information and comprise a new representation of reality. Medical experts, unfamiliar with this new representation, form a groupware for the task of interpreting them and providing better services to the patient. Groupware procedures, facilitated by modern network technology, bring experts' tacit knowledge to the surface and facilitate its exchange.

Functional diagnosis of residual lymphomas after radiochemotherapy with positron emission tomography comparing FDG- and FLT-PET

Positron emission tomography (PET) using 2-deoxy-2-[(18)F]fluoro-D-glucose (FDG) is used as a functional imaging technique for the staging and follow-up of lymphomas. However, additional information about the tumor proliferation rate using 3'-deoxy-3'-[(18)F]fluorothymidine (FLT) may be useful for the assessment of prognosis. We enrolled 48 patients with Hodgkin's (n = 15) and non-Hodgkin's lymphoma (n = 33) with residual masses >2 cm examined by tracer studies with FDG and FLT. The results were related to median overall and progression-free survival. In 15 out of 48 patients analysed using FDG, positive results were found. Using FLT, 10 out of 48 patients were positive. 33 patients were FDG negative. Eight patients were positive both using FDG and FLT. Overall survival for patients with a negative PET scan was significantly higher than for patients with positive PET, irrespective of the tracer used. FLT alone was able to discriminate between patients with long or short overall survival. However, there was no statistical significance comparing FDG/FLT negative versus FDG negative alone. Although FDG detected more lesions than did FLT, the additional biological characterization of tumor tissue with respect to proliferation by FLT might be useful by providing complementary information for the identification of recurrence. However, the present data show no advantage of combined FDG/FLT studies over FDG alone with respect to the prediction of survival.

Is contrast-enhanced US alternative to spiral CT in the assessment of treatment outcome of radiofrequency ablation in hepatocellular carcinoma?

PURPOSE

The present study was conducted to assess the efficacy of contrast-enhanced ultrasound with low mechanical index in evaluating the response of percutaneous radiofrequency ablation treatment of hepatocellular carcinoma by comparing it with 4-row spiral computed tomography.

MATERIALS AND METHODS

100 consecutive patients (65 men and 35 women; age range: 62 - 76 years) with solitary hepatocellular carcinomas (mean lesion diameter: 3.7 cm +/- 1.1 cm SD) underwent internally cooled radiofrequency ablation. Therapeutic response was evaluated at one month after the treatment with triple-phasic contrast-enhanced spiral CT and low-mechanical index contrast-enhanced ultrasound following bolus injection of 2.4 ml of Sonovue (Bracco, Milan). 60 out of 100 patients were followed up for another 3 months. Contrast-enhanced sonographic studies were reviewed by two blinded radiologists in consensus. Sensitivity, specificity, NPV and PPV of contrast-enhanced ultrasound examination were determined.

RESULTS

After treatment, contrast-enhanced ultrasound identified persistent signal enhancement in 24 patients (24 %), whereas no intratumoral enhancement was detected in the remaining 76 patients (76 %). Using CT imaging as gold standard, the sensitivity, specificity, NPV, and PPV of contrast enhanced ultrasound were 92.3 % (95 % CI = 75.9 - 97.9 %), 100 % (95 % CI = 95.2 - 100 %), 97.4 % (95 % CI = 91.1 - 99.3 %), and 100 % (95 % CI = 86.2 - 100 %).

CONCLUSION

Contrast-enhanced ultrasound with low mechanical index using Sonovue is a feasible tool in evaluating the response of hepatocellular carcinoma to radiofrequency ablation. Accuracy is comparable to 4-row spiral CT.

Assessment of the incremental value of recombinant thyrotropin stimulation before 2-[18F]-Fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography imaging to localize residual differentiated thyroid cancer

PURPOSE

The purpose of the study was to assess prospectively the impact of recombinant human TSH (rhTSH) administration on positron emission tomography (PET)/computed tomography (CT) imaging in differentiated thyroid cancer patients who, after primary treatment, had a suppressed or stimulated serum thyroglobulin greater than 10 ng/ml and no radioactive iodine uptake consistent with thyroid cancer on a whole body scan.

PATIENTS AND METHODS

PET/CT was performed before (basal PET) and 24-48 h after rhTSH administration (rhTSH-PET) in 63 patients (52 papillary and 11 follicular thyroid cancers). Images were blindly analyzed by two readers. The proposed treatment plan was prospectively assessed before basal PET, after basal PET, and again after rhTSH-PET.

RESULTS

A total of 108 lesions were detected in 48 organs in 30 patients. rhTSH-PET was significantly more sensitive than basal PET for the detection of lesions (95 vs. 81%; P = 0.001) and tended to be more sensitive for the detection of involved organs (94 vs. 79%; P = 0.054). However, basal PET and rhTSH-PET did not have significantly different sensitivity for detecting patients with any lesions (49 vs. 54%; P = 0.42). Changes in treatment management plan occurred in 19% of the patients after basal PET. Lesions found only by rhTSH-PET contributed to an altered therapeutic plan in eight patients, among whom only four were true-positive on pathology (6%).

CONCLUSION

The use of rhTSH for 2-[18F]-fluoro-2-deoxy-D-glucose-PET/CT significantly increased the number of lesions detected, but the numbers of patients in whom any lesion was detected were no different between basal and rhTSH-stimulated PET/CT scans. Treatment changes due to true positive lesions occurred in 6% of cases.

Usefulness of fluorine-18 fluorodeoxyglucose positron emission tomography in patients with a residual structural abnormality after definitive treatment for squamous cell carcinoma of the head and neck

BACKGROUND

Residual structural abnormalities after definitive treatment of head and neck squamous cell carcinoma (HNSCC) are common and pose difficult management problems. The usefulness of fluorine-18 fluorodeoxyglucose positron emission tomography (FDG PET) to supplement conventional evaluation with clinical and standard radiologic examination (CE) in such patients was assessed.

METHODS

Fifty-three eligible patients were identified with residual structural abnormalities on CE. True disease extent could be validated in 46 patients. Patients had a median potential follow-up of 55 months (range, 41-75 months) from the date of PET scan to the analysis closeout date.

RESULTS

PET had better diagnostic accuracy than CE (p = .0002) and induced management change in 21 patients (40%; 95% confidence interval [CI], 26%-54%), including avoidance of unnecessary planned surgery in 14 patients with negative PET. Appropriate management change was confirmed in 19 (95%) of 20 evaluable cases. Disease presence and extent assessment by PET were significant predictors of survival (p < .0001), whereas the extent of disease determined by CE was not.

CONCLUSION

PET added significantly to the value of CE in restaging disease in patients with structural abnormalities after definitive treatment of HNSCC. Management decisions based on PET were appropriate in most patients.

[The approach to tumors of the retrocrural mediastinum]

Retrocrural tumors of the lower posterior mediastinum are rare. Most tumors in this region involve lymphatic metastasis of germ cell tumors. Formerly these tumors were resected through a combined thoracoabdominal approach, with division of the diaphragm and effecting an at least partial phrenic paresis. The ventral approach via bilateral subcostal incision with cranial extension avoids this problem and allows a bilateral access to the retrocrural space. From November 1999 to December 2005, using this approach we operated on 12 patients with residual germ cell tumors after chemotherapy. In all cases radical resection was obtained. Intra- or postoperative complications did not occur. All patients are still alive and free of disease.

Radioguided Intraoperative Margins Evaluation (RIME): Preliminary results of a new technique to aid breast cancer resection

AIMS

Women undergoing breast-conserving surgery for cancer can present residual disease. We have developed a technique called Radioguided Intraoperative Margins Evaluation (RIME) that uses a radiopharmaceutical to distinguish normal and cancer tissues. The aim of this study was to assess whether RIME is a feasible technique, and if it could help in breast cancer resection with free margins, minimizing residual disease.

METHODS

Twenty-three breast cancer patients programmed for mastectomy were selected. Before surgery, the patients were submitted to scintimammography with 99mTc-sestamibi to estimate the optimal time to begin radioguided surgery. Twenty patients were submitted to magnetic resonance imaging (MRI), to evaluate skin, deep fascia and to detect other tumor foci. At the beginning of the surgery, the same dose of 99mTc-sestamibi was intravenously injected into patients. Tumor resection was performed under guidance of a gamma-probe, characterizing the RIME technique. Finally, modified radical mastectomy was performed. Tumor and residual breast were histopathologically examined.

RESULTS

The RIME technique was successfully performed in all patients. The principal tumor was removed by this technique and provided 82.6% of histologically free margins (mean margins, 4.8 mm). Additionally, 47.8% of patients were without residual disease. The mean size of residual carcinoma was 3.67 mm and generally located near the tumor bed (<1.5 cm). There was no significant association between presence of residual disease and tumor size or margin status.

CONCLUSION

RIME is a feasible technique that could help tumor resection with free margins; however, it seems to be limited for small carcinoma foci.

2-[18F]fluoro-2-deoxyglucose positron-emission tomography in staging, response evaluation, and treatment planning of lymphomas

2-[18F]fluoro-2-deoxyglucose positron-emission tomography (FDG-PET) is used increasingly in the clinical management of lymphomas. With regard to staging, FDG-PET is more sensitive and specific than conventional staging methods in FDG avid lymphomas (ie, Hodgkin lymphoma and most aggressive non-Hodgkin lymphomas). Despite methodological problems, in particular the lack of a valid reference test, FDG-PET is approved and generally used for this purpose. With regard to response evaluation, FDG-PET at the end of treatment seems to aid considerably in differentiating between residual masses with or without residual lymphoma. Hence, new revised response criteria have been proposed, incorporating the result of FDG-PET at the end of treatment. An early interim FDG-PET scan after 1 to 3 cycles of chemotherapy is a very strong predictor of outcome, and trials are now in progress testing treatment modifications on this basis. With regard to treatment planning, in the context of combined-modality therapy, radiotherapy for lymphomas is moving toward more conformal techniques reducing the irradiated volume to include only the macroscopic lymphoma. In this situation, accurate imaging is essential, and FDG-PET coregistered with the planning computed tomography (CT) scan is used increasingly. The availability of PET/CT scanners suited for virtual simulation has aided this process. However, clinical data evaluating this technique are at present sparse.

Early assessment of clinical response to concurrent chemoradiotherapy in head and neck carcinoma using fluoro-2-deoxy-d-glucose positron emission tomography

OBJECTIVES

The aim of this study is to assess the utility of FDG-PET in the evaluation of therapeutic effects at 4 weeks after the completion of the concurrent chemoradiotherapy (CCR) in patients with head and neck squamous cell carcinoma (HNSCC).

METHODS

Thirty-one patients with previously untreated HNSCC were retrospectively investigated about FDG-PET, CT, MRI and biopsies of the carcinoma before and 4 weeks after the treatment.

RESULTS

The results of pathological examinations after CCR showed 6 residual cases and 25 ones with a pathologically complete response (pCR). The specificity of FDG-PET was 80%, although the sensitivity was limited to 67%.

CONCLUSIONS

FDG-PET has a high specificity but limited sensitivity to discriminate residual cancer from fibrosis or scar at 4 weeks after CCR. FDG-PET at 4 weeks after CCR was too early to perform because of limited sensitivity.

R1-Resektion in der Chirurgie des oberen Gastrointestinaltrakts

Microscopically involved tumor margins are an important problem in the surgery of locally advanced esophageal and gastric carcinomas. We conducted a systematic review of the literature and a specific analysis of our own patient database. This article summarizes current knowledge of the incidence and prognosis of R1 resections in upper gastrointestinal cancers. Preoperative strategies for reducing the rate of R1 resections are presented, and the surgical options in case of R1 resection are discussed.

18F-choline and/or 11C-acetate positron emission tomography: detection of residual or progressive subclinical disease at very low prostate-specific antigen values (<1 ng/mL) after radical prostatectomy

OBJECTIVES

To assess the value of positron emission tomography (PET)/computed tomography (CT) with either (18)F-choline and/or (11)C-acetate, of residual or recurrent tumour after radical prostatectomy (RP) in patients with a prostate-specific antigen (PSA) level of <1 ng/mL and referred for adjuvant or salvage radiotherapy.

PATIENTS AND METHODS

In all, 22 PET/CT studies were performed, 11 with (18)F-choline (group A) and 11 with (11)C-acetate (group B), in 20 consecutive patients (two undergoing PET/CT scans with both tracers). The median (range) PSA level before PET/CT was 0.33 (0.08-0.76) ng/mL. Endorectal-coil magnetic resonance imaging (MRI) was used in 18 patients. Nineteen patients were eligible for evaluation of biochemical response after salvage radiotherapy.

RESULTS

There was abnormal local tracer uptake in five and six patients in group A and B, respectively. Except for a single positive obturator lymph node, there was no other site of metastasis. In the two patients evaluated with both tracers there was no pathological uptake. Endorectal MRI was locally positive in 15 of 18 patients; 12 of 19 responded with a marked decrease in PSA level (half or more from baseline) 6 months after salvage radiotherapy.

CONCLUSIONS

Although (18)F-choline and (11)C-acetate PET/CT studies succeeded in detecting local residual or recurrent disease in about half the patients with PSA levels of <1 ng/mL after RP, these studies cannot yet be recommended as a standard diagnostic tool for early relapse or suspicion of subclinical minimally persistent disease after surgery. Endorectal MRI might be more helpful, especially in patients with a low likelihood of distant metastases. Nevertheless, further research with (18)F-choline and/or (11)C-acetate PET with optimal spatial resolution might be needed for patients with a high risk of distant relapse after RP even at low PSA values.

3′-deoxy-3′-18F-fluorothymidine (FLT) Positron Emission Tomography for Early Prediction of Response to Chemoradiotherapy – A Clinical Application Model of Esophageal Cancer

Early detection of response to neoadjuvant chemoradiation in esophageal cancer may allow individualization of treatment strategies and avoidance of unnecessary treatment. Although positron emission tomography (PET) with [(18)F]fluorodeoxyglucose (FDG) permits detection of changes in tumor proliferation before any change in tumor size is evident, FDG-PET may fail to distinguish between residual tumor and inflammation and between complete response and partial response with substantial residual tumor burden. PET with the nucleoside analogue 3'-deoxy-3'-(18)F-fluorothymidine (FLT) is more accurate than FDG-PET in visualizing early changes in tumor proliferation. In a recent study in experimental models of esophageal cancer, FLT-PET was more accurate than FDG-PET in detecting early changes in proliferation following docetaxel and radiation therapy in human SEG-1 cells and mouse SEG-1 xenografts, including having a much stronger correlation with histologic findings. Clinical studies are needed to determine if FLT-PET can distinguish among degrees of response to neoadjuvant chemoradiation in patients with esophageal cancer. The ability to visualize tumor cell proliferation may also contribute to the ability to improve precision delivery of radiation therapy.

[Roles of single photo emission computed tomography-CT in detecting residual tumor from patients with thyroid carcinoma]

OBJECTIVE

As newly, functional, diagnostic measure-18F-deoxyglucose single photo emission computed tomography (18F-FDG SPECT-CT) has well sensitivity and specialty , it was proved availability in differentiating benign and malignant tumor. In this study, it was compared the efficiency of detecting residual tumor of thyroid cancer between 18F-FDG SPECT-CT and CT-TWIN.

METHODS

During May 2004 to August 2004, 56 patients with thyroid disease were divided into two groups, one group was 32 cases suffered thyroid tumor, another was 24 cases suffered improper operation. All cases must take 18F-FDG SPECT-CT and CT-TWIN.

RESULTS

Forty eight cases had been performed operation, and 8 cases waited and watched because they didn't be found residual tumor by 18F-FDG SPECT-CT and CT-TWIN. The results in detecting thyroid tumor showed that the same rate of diagnostic correction of SPECT-CT was 87.5% (28/32), and the Youden index of SPECT-CT was 0.667, higher than that of CT which was 87.5% (28/32) and 0.633 respectively. When the results two methods were accordant, the rate of diagnostic correction was 100% (24/24), and Youden index was 1, and the result had statistic signification. The rate of diagnostic correction of SPECT-CT in detecting residual tumor was 84.6%, and its Youden index was 0.675. The rate of diagnostic correction of CT in detecting residual tumor was 75.0%, and its Youden index was 0.492; and the result had statistics signification by being compared two different measures.

CONCLUSIONS

SPECT-CT and CT all had higher diagnostic efficacy, and they could promote the diagnostic efficacy when they have the same diagnosis in detecting thyroid tumor. The rate of detecting residual tumor of SPECT-CT was 81.3%, compared with that of CT the diagnostic efficacy has greater raise.

Late relapse of metastatic non-seminomatous testicular germ cell tumours

Although the majority of men presenting with non-seminomatous germ cell tumours (NSGCT) are cured, late relapse (occurring more than 2 years after obtaining a complete response to treatment) is increasingly recognized. The typical patterns of disease spread have been well-documented, but the findings at late relapse are more variable and less well-described. We discuss the phenomenon of late relapse, the characteristics of teratoma differentiated (TD), and the issue of long-term imaging surveillance of patients with NSGCT. The potential sites of late relapse of NSGCT and the associated spectrum of imaging appearances are illustrated.

18F-FDG-PET for evaluation of the response to concurrent chemoradiation therapy with intensity-modulated radiation technique for Stage T4 nasopharyngeal carcinoma

PURPOSE

This article evaluates [18F] fluorodeoxyglucose positron emission tomography (18F-FDG-PET) findings as a predictor for local responders (R) vs. nonresponders (NR) in nasopharyngeal carcinoma (NPC) patients with Stage T4 lesions, before and at 3 months after completion of concurrent chemotherapy and radiation therapy (CCRT).

METHODS AND MATERIALS

From January 2002 to November 2003, 39 T4 NPC patients were enrolled. All had magnetic resonance imaging and 18F-FDG-PET, both before and 3 months after CCRT. Any residual/recurrent lesions were confirmed histopathologically.

RESULTS

Of the 39 eligible patients, after a follow-up of 24.2 +/- 9.5 months, 35 became disease-free and 4 had residual or recurrent disease. Marginal differences in standard uptake values (SUV) were observed (10.9 +/- 5.3 vs. 15.6 +/- 3.4, p = 0.058) between R and NR before treatment, and value changes of SUV before and after CCRT were not significantly different. However, highly significantly lower values of SUV were noted for R than for NR 3 months after completion of CCRT (2.1 +/- 0.8 vs. 5.5 +/- 3.2, p = 0.001). One hundred percent positive and negative predictive values were observed for SUV values of 4.0, set 3 months after completion of CCRT.

CONCLUSIONS

Neither the pretreatment SUV nor the changes of SUV between pretreatment and posttreatment were significant predictors for local response. SUV at 3 months after completion of CCRT was a significant determinator for local response. The cutoff of 4.0 for SUV at 3 months after completion of CCRT was useful to be offered as a diagnostic reference for recurrent or residual tumor for NPC treatment.

Complete response of colorectal liver metastases after chemotherapy: does it mean cure?

PURPOSE

Most patients with colorectal liver metastases (LMs) receive systemic chemotherapy. This study aimed to determine the significance of a complete response on imaging of LMs after chemotherapy.

PATIENTS AND METHODS

Between 1998 and 2004, 586 patients were treated for colorectal LMs in one institution. Of these, 38 with the following criteria were included in the study: fewer than 10 LMs before chemotherapy; disappearance of one or several LMs on computed tomography (CT) scan and ultrasound; surgery with intraoperative ultrasound within 4 weeks of imaging; no extrahepatic disease; follow-up at least 1 year after surgery.

RESULTS

Overall, 66 LMs disappeared after chemotherapy as seen on CT scan. Persistent macroscopic disease was observed at surgery at the site of 20 of 66 LMs, despite CT scan showing a complete response. The sites of 15 initial LMs that were not visible at surgery were resected. Pathologic examination of these sites of LMs, considered in complete response, showed viable cancer cells present in 12 of 15 cases. The sites of 31 initial LMs that were not visible at surgery were left in place during surgery; after 1 year of follow-up, 23 of 31 LMs considered in complete response had recurred in situ. Overall, persistent macroscopic or microscopic residual disease or early recurrence in situ were observed in 55 (83%) of 66 LMs having a complete response on imaging.

CONCLUSION

In most patients receiving chemotherapy for colorectal LMs, a complete response on CT scan does not mean cure.

Posttreatment assessment of response using FDG-PET/CT for patients treated with definitive radiation therapy for head and neck cancers

PURPOSE

The goal of this study was to evaluate coregistered [18F] fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) for the detection of persistent disease after definitive radiation therapy in head and neck cancer.

METHODS AND MATERIALS

Posttreatment FDG-PET/CT was performed in 28 patients on average 8 weeks (range, 4 to 15.7 weeks) after completing definitive radiation therapy. FDG-PET/CT was visually analyzed for the entire patient group and at two time points (4-8 and >8 weeks) after treatment. The contrast-enhanced CT portion of PET/CT was separately analyzed blinded to the results of coregistered FDG-PET/CT and classified as negative or positive for residual locoregional disease. Pathologic findings and clinical follow-up served as the reference standard.

RESULTS

Follow-up data were available for all 28 patients (median, 17.6 months). Regarding the detection of residual disease, the overall sensitivity and specificity of FDG-PET/CT was 76.9% and 93.3%, respectively, compared with 92.3% and 46.7% for contrast-enhanced CT. The accuracy of FDG-PET/CT was 85.7%, compared with 67.9% for CT alone. All false-negative (n = 3) and false-positive (n = 1) FDG-PET/CT results occurred between 4 and 8 weeks after treatment. At 8 weeks or later after treatment, the specificity of CT was 28%, compared with 100% for FDG-PET/CT.

CONCLUSIONS

The metabolic-anatomic information from coregistered FDG-PET/CT provided the most accurate assessment for treatment response when performed later than 8 weeks after the conclusion of radiation therapy. FDG-PET/CT excelled by a higher specificity and overall diagnostic performance than CT imaging alone. These results support a potential clinical role of FDG-PET/CT in the early assessment of therapy response after definitive radiation therapy.

Flash-echo contrast sonography in the evaluation of response of small hepatocellular carcinoma to percutaneous ablation

PURPOSE

To evaluate the use of flash-echo contrast sonography (FECS) in subtraction mode in assessing small hepatocellular carcinoma (HCC) after percutaneous local ablation therapy.

METHODS

Between March 2000 and February 2002, we prospectively assessed small HCCs after percutaneous local ablation therapy using FECS in subtraction mode. Thirty-three patients (22 men, 11 women) with 35 tumors ranging in size from 1.1 to 3.0 cm (mean +/- SD, 2.0 +/- 0.5) were enrolled. Twenty-one tumors received percutaneous ethanol injection only, 13 tumors received percutaneous microwave ablation therapy only, and the remaining tumor received both treatments. CT, hepatic angiography, and follow-up were used as gold standards in analyzing the accuracy of FECS in detecting residual tumors.

RESULTS

The agreements between FECS and CT, FECS and hepatic angiography, and all 3 imaging modalities were 80% (28/35), 85.7% (30/35), and 77.1% (27/35), respectively. Twenty-one patients with 23 completely ablated tumors were followed up for 5 to 39 months (mean +/- SD, 20.2 +/- 11.2). Recurrent disease was detected in 11 (52.4%) patients; local tumor recurrence occurred in 4 (17.4%) patients. The sensitivity, specificity, accuracy, and positive and negative predictive value of FECS in detecting viable tumors were 53.8% (7/13), 90.9% (20/22), 77.1% (27/35), 77.8% (7/9), and 76.9% (20/26), respectively.

CONCLUSIONS

FECS in subtraction mode shows good agreement with hepatic angiography and CT in the assessment of small HCC after percutaneous local ablation therapy. The sensitivity of FECS in detecting residual tumors is suboptimal.

Utility of Positron Emission Tomography-Computed Tomography in Identification of Residual Nodal Disease after Chemoradiation for Advanced Head and Neck Cancer

OBJECTIVES

Planned neck dissection after chemoradiation (CR) is often advocated in patients with head and neck squamous cell cancer (HNSCC) with advanced nodal disease who demonstrate a clinical complete response to CR because identification of residual occult nodal disease is difficult. We sought to investigate the utility of positron emission tomography-computed tomography (PET-CT) in identifying patients with occult nodal disease after CR.

STUDY DESIGN

Nonrandomized retrospective cohort analysis.

MATERIALS AND METHODS

The medical records of all patients treated with primary CR for advanced HNSCC with N2 or N3 disease from December 2003 to June 2005 were reviewed. Patients with a clinical complete response were eligible for inclusion if PET-CT performed at 8 to 10 weeks after CR showed no evidence of distant disease and they were treated with a planned neck dissection.

RESULTS

Seventeen patients met study criteria. PET-CT was positive for residual nodal disease in 11 (64.7%) patients, with a standardized uptake value (SUV) range of 1.7 to 3.8. Pathologic examination revealed residual viable carcinoma in five (29.4%) patients, with tumor size ranging from 2.0 to 9.5 mm. Carcinoma was present in 2 of 11 (18.2%) patients with positive PET-CT scans and 3 of 6 (50%) patients with negative PET-CT scans. The sensitivity and specificity of PET-CT in predicting occult nodal disease was 40% and 25%, respectively. There was no correlation between PET-CT findings and histologic findings (P = .26) or between SUV and size of viable tumor (P = .67).

CONCLUSIONS

A significant proportion of HNSCC patients with advanced neck disease harbor residual occult metastases after CR. PET-CT is not sufficiently specific or sensitive to reliably predict the need for posttreatment neck dissection.

FDG-PET in 10 children with non-Hodgkin's lymphoma: initial experience in staging and follow-up

BACKGROUND

The use of FDG-PET was evaluated for initial staging and therapy efficacy in paediatric patients with non-Hodgkin's lymphoma (NHL) and compared to the established conventional imaging modalities (CIM). The results of this retrospective analysis are presented in conjunction with a critical review of the current literature.

PATIENTS AND METHODS

Ten paediatric patients with NHL were examined using whole-body FDG-PET initially (n = 6), during therapy (n = 5) and after completion of therapy (n = 5), respectively. FDG-PET findings were compared to CIM performed according to the protocol of the German NHL-BFM 95 study. The results were evaluated for their impact on disease classification and therapy decision (St. Jude, REAL) in correspondence to a clinical follow-up of at least 24 months.

RESULTS

Concerning initial staging, all lymphoma manifestations detected by conventional imaging were also detected by FDG-PET (15 nodal, 2 extranodal). Furthermore, an additional nodal lesion was detected by FDG-PET in three patients. This resulted in an upstaging followed by an intensified poly-chemotherapy in one patient. In five patients showing unclear residual masses on conventional imaging during therapy, FDG-PET indicated viable residual tumours in one case. This patient showed a relapse during follow-up while the four FDG-PET negative patients did not. After completion of initial therapy, FDG-PET revealed in one out of five patients persistent tumour metabolism in the primary lesions and also detected new manifestations. The patient died shortly after restaging due to disease progression.

CONCLUSIONS

These first results on the use of FDG-PET in paediatric non-Hodgkin lymphoma indicate a high potential to improve the therapeutic management.

Accuracy of physical examination, ultrasonography, and mammography in predicting residual pathologic tumor size in patients treated with neoadjuvant chemotherapy

OBJECTIVE

To assess the accuracy of physical examination, ultrasonography, and mammography in predicting residual size of breast tumors following neoadjuvant chemotherapy.

BACKGROUND

Neoadjuvant chemotherapy is an accepted part of the management of stage II and III breast cancer. Accurate prediction of residual pathologic tumor size after neoadjuvant chemotherapy is critical in guiding surgical therapy. Although physical examination, ultrasonography, and mammography have all been used to predict residual tumor size, there have been conflicting reports about the accuracy of these methods in the neoadjuvant setting.

METHODS

We reviewed the records of 189 patients who participated in 1 of 2 protocols using doxorubicin-containing neoadjuvant chemotherapy, and who had assessment by physical examination, ultrasonography, and/or mammography no more than 60 days before their surgical resection. Size correlations were performed using Spearman rho analysis. Clinical and pathologic measurements were also compared categorically using the weighted kappa statistic.

RESULTS

Size estimates by physical examination, ultrasonography, and mammography were only moderately correlated with residual pathologic tumor size after neoadjuvant chemotherapy (correlation coefficients: 0.42, 0.42, and 0.41, respectively), with an accuracy of +/-1 cm in 66% of patients by physical examination, 75% by ultrasonography, and 70% by mammography. Kappa values (0.24-0.35) indicated poor agreement between clinical and pathologic measurements.

CONCLUSION

Physical examination, ultrasonography, and mammography were only moderately useful for predicting residual pathologic tumor size after neoadjuvant chemotherapy.

Breast-conserving surgery after chemotherapy: value of MDCT for determining tumor distribution and shrinkage pattern

OBJECTIVE

For this study, we investigated the usefulness of MDCT in assessing the extent of residual breast cancer after neoadjuvant chemotherapy. To ensure the success of breast-conserving surgery, we evaluated the usefulness of determining the tumor distribution before neoadjuvant chemotherapy and the shrinkage pattern after neoadjuvant chemotherapy.

SUBJECTS AND METHODS

MDCT before and after neoadjuvant chemotherapy was performed in 46 consecutive patients with 47 locally advanced breast cancers. The distribution pattern of contrast enhancement on MDCT before neoadjuvant chemotherapy was classified into five categories: solitary lesion, grouped lesion (localized lesion with linear, spotty, or linear and spotty enhancement), separated lesion (multiple foci of contrast enhancement), mixed lesion (grouped lesion with multiple foci), and replaced lesion (diffuse contrast enhancement in whole quadrants).

RESULTS

There was agreement between the MDCT assessment and pathologic findings in 44 (94%) of the 47 tumors. In the partial response group with nonreplaced lesions, MDCT revealed three shrinkage patterns: pattern 1a, concentric shrinkage without surrounding lesions; pattern 1b, concentric shrinkage with surrounding lesions; and pattern 2, shrinkage with residual multinodular lesions. Breast-conserving surgery was performed successfully in 14 patients including complete response cases that were detected on the basis of MDCT findings and partial response cases that were detected on the basis of observation of pattern 1 shrinkage. In all five patients with pattern 2 shrinkage, CT underestimated the residual tumor extent by more than 2 cm.

CONCLUSION

MDCT classification of tumor distribution before neoadjuvant chemotherapy and of shrinkage patterns after neoadjuvant chemotherapy is important in the preoperative evaluation of patients undergoing breast-conserving surgery.

Depiction of viable tumor in hepatocellular carcinoma treated with transarterial chemoembolization: multiphasic helical CT with review of the previous serial CT images

Objective

The purpose of our study was to assess whether a review of multiphasic helical CT combined with the previous serial CT images could be helpful to depict a viable tumor in hepatocellular carcinoma treated with transarterial chemoembolization.

Materials and Methods

Twenty-four consecutive patients with 35 hepatocellular carcinomas underwent transarterial chemoembolization followed by hepatic resection. First, three radiologists independently analyzed the last CT images taken before resection for the presence of viable tumor. A second analysis was then performed using the last CT combined with the previous serial CT images. The CT analyses were then compared with the pathologic results. The added value of the review of the previous serial CT images was evaluated by performing a receiver operating characteristic analysis. The sensitivity, specificity and diagnostic accuracy for the depiction of viable tumor were also assessed, and the characteristics of the false-negative lesions were pathologically evaluated.

Results

The mean diagnostic accuracies (Az values) for the depiction of viable tumor with using the last CT alone and with the review of the previous serial CT images for all observers were 0.885 and 0.901, respectively, which were not significantly difference (p > 0.05). However, the additional review of the previous serial CT images allowed the observers to render a correct diagnosis for three lesions that had been incorrectly diagnosed with the review of last CT alone. The sensitivity, specificity and diagnostic accuracy of the last CT along with the review of the previous serial CT images were 78%, 97% and 84%, respectively. All of the 16 false-negative lesions diagnosed by each observer showed 90% or greater necrosis on the pathologic examination.

Conclusion

For the depiction of viable tumor in hepatocellular carcinoma treated with transarterial chemoembolization, although the difference in the diagnostic accuracies was not statistically significant, a review of the multiphasic helical CT combined with the previous serial CT images could help reach a correct diagnosis for those lesions incorrectly diagnosed with the review of the last CT alone.

L-(methyl-11C) methionine positron emission tomography for target delineation in resected high-grade gliomas before radiotherapy

PURPOSE

Using magnetic resonance imaging (MRI), residual tumor cannot be differentiated from nonspecific postoperative changes in operated patients with brain gliomas. The higher specificity and sensitivity of L-(methyl-11C)-labeled methionine positron emissions tomography (MET-PET) in gliomas has been demonstrated in previous studies and is the rationale for the integration of this investigation in gross tumor volume delineation. The goal of this trial was to quantify the affect of MET-PET vs. with MRI in gross tumor volume definition for radiotherapy planning of high-grade gliomas.

METHODS AND MATERIALS

The trial included 39 patients with resected malignant gliomas. MRI and MET-PET data were coregistered based on mutual information. The residual tumor volume on MET-PET and the volume of tissue abnormalities on T1-weighted MRI (gadolinium [Gd] enhancement) and T2-weighted MRI (hyperintensity areas) were compared using MET-PET/MRI fusion images.

RESULTS

The MET-PET vs. Gd-enhanced T1-weighted MRI analysis was performed on 39 patients. In 5 patients (13%), MET uptake corresponded exactly with Gd enhancement, and in 29 (74%) of 39 patients, the region of MET uptake was larger than that of the Gd enhancement. In 27 (69%) of the 39 patients, the Gd enhancement area extended beyond the MET enhancement. MET uptake was detected up to 45 mm beyond the Gd enhancement. MET-PET vs. T2-weighted MRI was investigated in 18 patients. MET uptake did not correspond exactly with the hyperintensity areas on T2-weighted MRI in any patient. In 9 (50%) of 18 patients, MET uptake extended beyond the hyperintensity area on the T2-weighted MRI, and in 18 (100%), at least some hyperintensity on the T2-weighted MRI was located outside the MET enhancement area. MET uptake was detected up to 40 mm beyond the hyperintensity area on T2-weighted MRI.

CONCLUSION

In operated patients with brain gliomas, the size and location of residual MET uptake differs considerably from abnormalities found on postoperative MRI. Because postoperative changes cannot be differentiated from residual tumor by MRI, MET-PET, with a greater specificity for tumor tissue, can help to outline the gross tumor volume with greater accuracy.

Stereotactic radiosurgery for recurrent pleomorphic adenoma invading the skull base--case report--

A 38-year-old man presented with a recurrent pleomorphic adenoma in the parapharyngeal space invading the skull base 19 years after the first operation for a parotid gland tumor. Stereotactic radiotherapy was performed to control the tumor growth using a marginal dose of 8 Gy and maximum dose of 18 Gy with care taken to minimize the dose to nearby structures. The symptoms were reduced within a few months. Magnetic resonance imaging over 5 years showed that the tumor was controlled with no regrowth. Stereotactic radiotherapy is a therapeutic option for the treatment of pleomorphic adenomas.

Sonographic evaluation of early-stage breast cancers that undergo neoadjuvant chemotherapy

OBJECTIVE

We prospectively evaluated low-stage breast cancers treated with neoadjuvant chemotherapy using whole-volume sonography and color Doppler imaging.

METHODS

Thirty-four women with breast cancer (mean maximum size, 2.4 cm) received neoadjuvant chemotherapy with doxorubicin and docetaxel. Targeted whole-volume sonography of tumor sites was performed before and after chemotherapy to assess mass size, color pixel speed-weighted density, and American College of Radiology Breast Imaging Reporting and Data System sonographic characteristics. After chemotherapy, tumor sites were excised by lumpectomy or mastectomy.

RESULTS

Three (11.3%) of 34 patients had a complete histologic response. After chemotherapy, correlation was r = 0.716 between final histologic and sonographic sizes. Compared with histologic residual tumors, sonography had 4 false-negative results, 3 false-positive results, and 27 true-positive results (sensitivity, 87%), with no false-negative results among a subgroup of tumors of 7 mm and larger (sensitivity, 100%). The 3 cases with false-positive results were histologic fibrosis or biopsy changes. Mean speed-weighted density was 0.015 before and 0.0082 after chemotherapy (P = .03). After chemotherapy, vascularity was less common within (P = .06) or adjacent to (P = .009) masses or in tumor sites (P = .05). Prechemotherapy variables of gray scale characteristics and vascularity were compared with final histologic size, and all had P > .20.

CONCLUSIONS

Postchemotherapy sensitivity of sonography was high for residual tumors of 7 mm or larger. Correlation was moderate between histologic and sonographic final tumor sizes. False-positive results were caused by fibrosis or biopsy-related changes. False-negative results occurred with residual tumor size of 6 mm or smaller. After chemotherapy, vascularity usually decreased, and this was not specific for complete response. Before chemotherapy, no vascular or gray scale feature at initial imaging predicted complete responders.

Radiopaque coil insertion into breast cancers prior to neoadjuvant chemotherapy

Between May 1998 and December 2002, neoadjuvant chemotherapy was given to 81 women aiming to reduce tumour size and avoid mastectomy. A coil was inserted under ultrasound guidance into the tumour before treatment started. The impact of coil placement on subsequent surgery was assessed prospectively. Clinical response was seen in 69 patients and breast conservation was achieved in 60 cases. In 19 cases (23%) mammography and ultrasound were normal and localization was achieved exclusively by use of the coil. Eight of these 19 (10% of the total) had a complete pathological response; however in the remaining 11 cases (13%) there was residual invasive cancer. This study suggests that in patients undergoing neoadjuvant chemotherapy surgery is still appropriate even when clinical response appears complete. The use of the coil identifies 13% of patients with otherwise undetectable residual disease and is a valuable guide in identifying the site for further surgery.

Pre-ablative Diagnostic Whole-body Scan Following Total Thyroidectomy for Well-differentiated Thyroid Cancer: Is It Necessary?

OBJECTIVE

This study reviewed the incidence of positive pre-ablative diagnostic scan after total thyroidectomy and the efficacy of the current ablative dose. The predictive factors for outcome using a standard ablative dose and postoperative complications of total thyroidectomy were also examined.

METHODS

This was a retrospective review of patients referred for radioiodine ablation after total thyroidectomy between September 1997 and September 2001.

RESULTS

Forty patients were included in this study, of whom 95% had a positive scan after total thyroidectomy. Of the 30 patients who underwent standard 80-mCi radioiodine ablation, 21 (70%) had successful single ablation while the remaining nine patients needed a higher ablative dose. There were no significant differences between patients who had successful ablation with the standard dose and those who did not in terms of tumour size, patient age, lymph node status and extra-thyroidal extension. Fifteen percent suffered from permanent hypoparathyroidism requiring calcium supplementation. Three patients had documented recurrent laryngeal nerve paralysis.

CONCLUSION

Bypassing the pre-ablative diagnostic scan is feasible. The present ablation dose of 80 mCi of radioiodine is effective. The relatively high postoperative morbidity after difficult total thyroidectomy suggests less aggressive excision and postoperative radioiodine ablation of the remnant tissue.

Clinical value of different responses of serum thyroglobulin to recombinant human thyrotropin in the follow-up of patients with differentiated thyroid carcinoma

In the present study, we examined the clinical value of a differential response of thyroglobulin (Tg) concentration after recombinant human thyrotropin (rhTSH) stimulation (rhTSH Tg testing) and its correlation with (131)I uptake and whole body scanning (rhTSH-WBS) in 104 patients who had previously undergone near total thyroidectomy and (131)I ablation for differentiated thyroid carcinoma (DTC). RhTSH Tg testing was considered negative for rhTSH-Tg < 0.9 ng/mL, low positive for rhTSH-Tg of 1-5 ng/mL and high positive for rhTSHTg > 5 ng/mL. RhTSH Tg testing was negative in 70 patients, one of whom had a lymph-node metastasis, but no (131)I uptake. Seven patients had low positive rhTSH Tg testing and no (131)I uptake, but two of these patients had cervical lymph-node metastases. Twenty-seven patients had high positive rhTSH Tg testing and (131)I uptake was detected in lung, bone, or mediastinum in 11. Imaging techniques (CT, MRI, FDG-PET) documented metastatic disease in 22. In conclusion, our results suggest that any rise in rhTSH-Tg, even at low level, should raise the suspicion of persistent or recurrent DTC. Patients with rhTSH-Tg at high level should be carefully evaluated, since DTC persistence is highly probable. TSH-WBS provides little adjunctive information.

Resection of a cancer developing in the remnant pancreas after a pancreaticoduodenectomy for pancreas head cancer

We report a rare case of a curative resection performed on a carcinoma developing in the remnant pancreas at 3 years 7 months after a pancreaticoduodenectomy for pancreatic cancer. A 63-year-old man underwent a pancreaticoduodenectomy for pancreatic cancer on November 1999. Because the celiac trunk was occluded by atherosclerosis, an aortohepatic bypass with a saphenous vein graft was performed simultaneously. In May 2003, tumor marker levels increased, and a tumor was detected in the remnant pancreas on computed tomography. There were no findings such as invasion into the surrounding tissue or distant metastasis, and therefore we removed the remnant pancreas in July 2003. Histopathologically, the tumor consisted of a well-differentiated tubular adenocarcinoma and was limited to the pancreas. Moreover, the anastomotic site of the pancreaticojejunostomy was negative for cancer, and some foci of papillary hyperplasia and goblet cell metaplasia of the pancreatic ductal epithelium, which was thought to be the precursor of the pancreatic cancer, were seen. These findings suggested that the tumor was a second primary cancer developing in the remnant pancreas. This case provided suggestive evidence for the development of pancreatic cancer, and the surgical procedure for a pancreaticoduodenectomy with occlusion of the celiac trunk is discussed.

Detecting Postsurgical Recurrent Hepatocellular Carcinoma With Multiphasic Helical Computed Tomography

OBJECTIVE

The aim of this study was to assess the computed tomography (CT) patterns of postoperative recurrent hepatocellular carcinoma (HCC).

METHODS

Of 84 patients with histologically proven HCC by hepatectomies, multiphasic helical CT demonstrated 54 HCC lesions of intrahepatic recurrence in 31 (37%) patients. The initial and final appearances of HCC on hepatic arterial phase images were retrospectively determined by the serial CT scans, which were compared with appearances of primary HCC.

RESULTS

The initial appearances of 54 recurrent HCCs were identical to the appearances of primary HCC in 41 (76%) lesions. Serial changes from the initial appearance to the final appearance of recurrent HCC were observed in 10 (42%) of 24 lesions. The 13 discordant lesions and the 10 lesions with altered lesion vascularity in our series implied that at least 43% were of multicentric occurrence.

CONCLUSION

More than 40% of postoperative recurrent HCCs show intranodular hemodynamic changes. The incompatibility between CT findings of primary and recurrent HCCs implies that these tumors contain nodules of multicentric occurrence.

Early postoperative CT scanning for juvenile nasopharyngeal angiofibroma: detection of residual disease

BACKGROUND AND PURPOSE

High recurrence rates and early recurrence have been reported for juvenile nasopharyngeal angiofibroma (JNA) involving the skull base. The purpose of this study was to evaluate the diagnostic accuracy of contrast-enhanced CT scanning for the detection of residual disease (RD) in the early postoperative course after surgical excision of JNA.

METHODS

We retrospectively reviewed data in 20 male patients (mean age +/- SD, 15.4 +/- 5 years; range, 10-32 years) who underwent enhanced helical CT in the days after apparent complete surgical excision of JNA with initial expansion in the skull base. Four independent, blinded readers evaluated the occurrence of RD. Final diagnoses were rendered on the basis of histologic examination of excised specimens of RD or clinical and radiologic follow-up. The Cohen kappa test was performed to examine interreader agreement.

RESULTS

Postoperative contrast-enhanced CT had a sensitivity of 75%, a specificity of 83%, a positive predictive value of 75% and a negative predictive value of 83% for the detection of RD. The prevalence of RD was 40%. The base of pterygoids was the most frequent location of RD. Interreader agreement was high for the detection of putative RD (kappa=0.83). Variabilities in readers' interpretations were encountered for false-positive results and for disease in the foramen lacerum. False-negative results involved the base of pterygoids. Early postoperative CT scanning was well tolerated by all patients.

CONCLUSION

Contrast-enhanced helical CT is an accurate tool to evaluate excision of JNA in the days after surgery.

123I-IMT SPECT and 1H MR-spectroscopy at 3.0 T in the differential diagnosis of recurrent or residual gliomas: a comparative study

The aim of this investigation was to compare two current non-invasive modalities, single photon emission tomography (SPECT) using 123-iodine-alpha-methyl tyrosine (123I-IMT) and single-voxel proton magnetic resonance spectroscopy (1H-MRS) at 3.0 T, with regard to their ability to differentiate between residual/ recurrent tumors and treatment-related changes in patients pretreated for glioma. The patient population comprised 25 patients in whom recurrent glioma was suspected based on MR imaging. SPECT imaging started 10 min after iv. injection of 300-370 MBq 123I-IMT and was performed using a triple-head system. The IMT uptake was calculated semiquantitatively using regions-of-interest. 1H-MRS was performed at 3.0 T using the single-volume point-resolved spectroscopy (PRESS) technique. Guided by MR imaging volumes-of-interest for spectroscopy were placed into the suspected lesions. Signal intensities of choline-containing compounds (Cho), creatine and phosphocreatine (Cr), and N-acetylaspartate (NAA) were obtained. When using the cut-off of 1.62 for 123I-IMT uptake, the sensitivity, specificity, and accuracy of the 123I-IMT SPECT were 95, 100 and 96%, respectively. For 1H-MRS, the sensitivity, specificity and accuracy were 89, 83 and 88%, respectively, based both on the metabolic ratios of Cho/Cr and Cho/NAA as tumor criterion with cut-off values of 1.11 and 1.17, respectively. In conclusion, 123I-IMT SPECT yielded more favorable results compared to 1H-MRS at distinguishing recurrent and/or residual glioma from post-therapeutic changes and may be particularly valuable when the evaluation of tumor extent is necessary.

18F-fluorodeoxyglucose positron emission tomography in evaluation of germ cell tumor after chemotherapy

OBJECTIVES

To evaluate the role of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) in the assessment of germ cell tumors after chemotherapy.

METHODS

We reviewed patients' records for the histologic findings and clinical outcome. 18F-FDG PET results were correlated with tissue histologic features where available; and if not available, the correlation was with the clinical outcome.

RESULTS

A total of 45 PET studies were performed on 38 patients (age range 19 to 64 years, median 31). All patients had received chemotherapy. In the nonseminomatous germ cell tumor (NSGCT) group, of the 31 patients with one scan, 18 PET scans were reported as positive, with only 2 not having active disease. Of the 12 negative scans, 6 showed teratoma, 1 tumor, and 5 did not show active disease. The equivocal scan revealed thyroid adenoma. In the seminoma group, the PET scans correlated well with the clinical and histologic outcomes. Four patients underwent salvage chemotherapy, and in this subgroup, the PET findings also correlated with the outcome.

CONCLUSIONS

(18)F-FDG PET is a promising tool as an adjunct to current imaging techniques in detecting residual viable germ cell tumor after chemotherapy. In NSGCT, a positive PET scan was accurate in 16 of 18 patients, although negative PET studies did not exclude the presence of disease, mainly because of the presence of teratoma. In seminoma, a negative 18F-FDG PET study correlated with a favorable clinical outcome. PET was also predictive of the response to salvage chemotherapy and was highly specific for active tumor in both NSGCT and seminoma.

Current Strategies for Surgical Management and Adjuvant Treatment of Childhood Papillary Thyroid Carcinoma

Childhood papillary thyroid carcinoma is associated with more locally aggressive and more frequent distant disease than its adult counterpart. Recurrence rates tend to be higher in children, but cause-specific mortality remains low. Optimal initial treatment of childhood papillary thyroid carcinoma should include total or near-total thyroidectomy and central compartment node clearance. Modified neck dissections should be performed for biopsy-proven lateral neck disease. Every effort should be made to maintain parathyroid and laryngeal nerve function. Radical neck dissections are to be avoided. Radioiodine remnant ablation (RRA), appropriate thyroid hormone suppressive therapy (THST), and judicious use of therapeutic doses of (131)I are applied to achieve a disease-free status, which is most often confirmed by negative neck ultrasonography, negative whole-body scan (either withdrawal or recombinant human thyroid-stimulating hormone-stimulated), and extremely low levels of serum thyroglobulin. Appropriate utilization of (131)I, THST, repeat surgery, external beam radiotherapy, and rarely chemotherapy may provide long-term palliation and some cures in patients with recurrent/persistent disease. Follow-up should be lifelong, and the care of children after age 17 should subsequently be transferred to adult-care endocrinologists with expertise in managing thyroid neoplasia. Optimal surgical management can be achieved if adequate operations are routinely carried out by "high-volume" thyroid surgeons with expertise in the care of children. Nowhere is a multidisciplinary approach (endocrinologists, surgeons, nuclear medicine physicians, pediatricians, pathologists, oncologists) more critical than in the long-term management of papillary thyroid carcinoma that presents during childhood.