FDG uptake, glucose transporter type 1, and Ki-67 expressions in non-small-cell lung cancer: correlations and prognostic values

CT-derived body composition associated with lung cancer recurrence after surgery

OBJECTIVES

To evaluate the impact of body composition derived from computed tomography (CT) scans on postoperative lung cancer recurrence.

METHODS

We created a retrospective cohort of 363 lung cancer patients who underwent lung resections and had verified recurrence, death, or at least 5-year follow-up without either event. Five key body tissues and ten tumor features were automatically segmented and quantified based on preoperative whole-body CT scans (acquired as part of a PET-CT scan) and chest CT scans, respectively. Time-to-event analysis accounting for the competing event of death was performed to analyze the impact of body composition, tumor features, clinical information, and pathological features on lung cancer recurrence after surgery. The hazard ratio (HR) of normalized factors was used to assess individual significance univariately and in the combined models. The 5-fold cross-validated time-dependent receiver operating characteristics analysis, with an emphasis on the area under the 3-year ROC curve (AUC), was used to characterize the ability to predict lung cancer recurrence.

RESULTS

Body tissues that showed a standalone potential to predict lung cancer recurrence include visceral adipose tissue (VAT) volume (HR = 0.88, p = 0.047), subcutaneous adipose tissue (SAT) density (HR = 1.14, p = 0.034), inter-muscle adipose tissue (IMAT) volume (HR = 0.83, p = 0.002), muscle density (HR = 1.27, p < 0.001), and total fat volume (HR = 0.89, p = 0.050). The CT-derived muscular and tumor features significantly contributed to a model including clinicopathological factors, resulting in an AUC of 0.78 (95% CI: 0.75-0.83) to predict recurrence at 3 years.

CONCLUSIONS

Body composition features (e.g., muscle density, or muscle and inter-muscle adipose tissue volumes) can improve the prediction of recurrence when combined with clinicopathological factors.

Different prognostic outcomes in two cases of FDG-PET/CT-Positive and -negative cardiac angiosarcoma

Cardiac angiosarcoma is a rare malignant tumor with a poor prognosis, characterized by the high uptake of ¹⁸F-fluorodeoxyglucose (FDG). This case report presents two cases of cardiac angiosarcoma with a marked difference in FDG uptake and prognosis.Case Summary:Case 1: A 40-year-old male presented with syncope. Ultrasound echocardiography demonstrated a cardiac tumor with a high uptake of ¹⁸F-FDG (maximum standardized uptake value=9.2). The patient underwent heart catheterization and tumor biopsy. The pathological result was high-grade angiosarcoma, and the MIB-1(Ki-67) proliferation index was approximately 20%. Systemic chemotherapy was administered; however, the patient died 2 years and 5 months after disease onset.Case 2: A 65-year-old female had a right atrial tumor incidentally diagnosed during routine ultrasound echocardiography. The tumor exhibited a low uptake of ¹⁸F-FDG (maximum standardized uptake value=1.8). Open heart surgery was performed, and the tumor was completely resected. Histological analysis revealed low-grade angiosarcoma, and the MIB-1(Ki-67) proliferation index was less than 5%. The patient was followed-up and had not relapsed 2 years after surgery.Conclusion: ¹⁸F-FDG uptake may reflect pathological tumor grade and prognosis in cardiac angiosarcoma.

Do fine needle aspirate cytomorphological features correlate with positron emission tomography findings of metastatic non-small cell lung carcinoma in lymph nodes?

BACKGROUND

Our objective was to correlate cytomorphological features of metastatic non-small cell lung carcinoma (mNSCLC) with maximal standardized uptake value (mSUV) of positron emission tomography (PET) in Lymph nodes (LNs).

METHODS

Positive cytology slides of 114 LNs were reviewed from 100 patients with mNSCLC who had undergone PET study. Student's t-test was used for statistical comparisons.

RESULTS

Mean patients' age: 68.5, 54% male. LNs locations were: mediastinum: 99, lung hilum: 13, peribronchial: 1, axilla: 1. Final diagnoses were: Adenocarcinoma: 86, squamous cell carcinoma: 28 LNs. Within the adenocarcinoma subgroup, histological patterns correlate with mSUV. Acinar and papillary patterns were associated with significantly lower mSUVs (mean ± standard error (SE): 7.9 ± 0.9 and 9.2 ± 0.8, respectively) than solid pattern (13.0 ± 1.2; p values: 0.001 and 0.009, respectively). Similar difference exists between patterns associated with low- and high-grade adenocarcinoma (Mean ± SE: 9.2 ± 0.8 and 12.0 ± 1.0, respectively. p value: 0.02). Interestingly, micropapillary pattern was associated with the lowest mSUV amongst all patterns (Mean ± SE: 5.4 ± 1.1). Other features that correlated with higher mSUV were necrosis, moderate/severe nuclear atypia, lower lymphoid tissue yield, and contralateral LN involvement.

CONCLUSIONS

In LNs with mNSCLC, certain cytomorphological features are associated with higher mSUV. Micropapillary, a pattern considered as high-grade, is associated with lower SUV values; hence, a lower SUV threshold may raise concern for metastasis. Although high SUV is associated with LN metastasis, lower SUV levels in certain adenocarcinomas suggest correlation with clinical and morphological characteristics could be valuable in tailoring therapeutic management.

Is CT or FDG-PET more useful for evaluation of the treatment response in metastatic HER2-positive breast cancer? a case report and literature review

Response evaluation criteria in solid tumors version 1.1 (RECIST ver1.1) has been widely adopted to evaluate treatment efficacy in solid tumors, including breast cancer (BC), in clinical trials and clinical practice. RECIST is based mainly on computed tomography (CT) images, and the role of fluorodeoxyglucose-positron emission tomography (FDG-PET) is limited. However, because the rate of tumor shrinkage on CT does not necessarily reflect the potential remaining tumor cells, there may be a discrepancy between the treatment response and prognosis in some cases. Here we report a case of metastatic human epidermal growth factor receptor 2 (HER2)-positive BC where FDG-PET was preferable to CT for evaluation of the treatment response. A 40-year-old woman became aware of a lump in her right breast in September 201X. She was pregnant and underwent further examinations, including a biopsy, in November. The diagnosis was HER2-positive BC (cT2N2bM1, stage IV). Trastuzumab plus pertuzumab plus docetaxel (TPD) therapy was initiated in December 201X. CT performed in February 201X+1 showed cystic changes in the metastatic lesions in the liver, and the treatment response was stable disease (SD) according to RECIST. However, FDG-PET in March 201X+1 did not detect abnormal uptake of FDG in the hepatic lesions. The disease remained stable thereafter. Thus, tumor shrinkage may not be apparent in situations where the response to treatment results in rapid changes in blood flow within the tumor, which is associated with cystic changes. When patients with hypervascular liver metastases receive treatment with highly effective regimens, the target lesion may show cystic changes rather than shrinkage, as observed in the present case. Therefore, FDG-PET is sometimes superior to CT in judging a tumor response.

Glucose transporters as markers of diagnosis and prognosis in cancer diseases

The primary metabolic substrate for cells is glucose, which acts as both a source of energy and a substrate in several processes. However, being lipophilic, the cell membrane is impermeable to glucose and specific carrier proteins are needed to allow transport. In contrast to normal cells, cancer cells are more likely to generate energy by glycolysis; as this process generates fewer molecules of adenosine triphosphate (ATP) than complete oxidative breakdown, more glucose molecules are needed. The increased demand for glucose in cancer cells is satisfied by overexpression of a number of glucose transporters, and decreased levels of others. As specific correlations have been observed between the occurrence of cancer and the expression of glucose carrier proteins, the presence of changes in expression of glucose transporters may be treated as a marker of diagnosis and/or prognosis for cancer patients.

Analysis of the F-18 FDG PET/CT features of pulmonary sclerosing pneumocytoma

PURPOSE

This retrospective study aimed to analyzed the F-18 fluorodeoxyglucose PET/computed tomography (F-18 FDG PET/CT) features of pulmonary sclerosing pneumocytoma (PSP) to improve the understanding and preoperative diagnostic efficacy of this rare disorder.

METHODS

FDG PET/CT images from 11 patients with 22 lesions (including one patient with 12 lesions) proven PSP in our hospital were reviewed. We summarized the PET/CT features of PSP and analyzed the correlation between FDG uptake and tumor size.

RESULTS

PET/CT imaging revealed all tumors located in each lobe of the two lungs randomly. All 22 tumors were round or oval nodules; 15 had smooth margins, six were lobulated, six were calcified, and one had a ground-glass halo sign. The mean diameter of these tumors was 19.2 ± 7.8 mm (range: 8-34 mm); the mean maximum standardized uptake value (SUVmax) was 2.8 ± 1.3 (range: 1.1-7.4). Sixteen of the lesions exhibited mild to moderate FDG uptake (mean SUVmax 2.3 ± 0.6), and six of the lesions exhibited intense FDG uptake (mean SUVmax 4.3 ± 1.6). A positive correlation was observed between FDG uptake and tumor size (P <0.05).

CONCLUSION

Single round or ovoid soft-tissue lesions with smooth margins, and mild to moderate FDG uptake on PET/CT images in middle-aged females, suggest a possible diagnosis of PSP. For some atypical cases with intense FDG uptake, a diagnosis of PSP also can be considered. A statistically significant positive correlation was found between SUVmax and PSP lesion size in our study.

A Noninvasive Assessment of Tumor Proliferation in Lung cancer Patients using Intravoxel Incoherent Motion Magnetic Resonance Imaging

Ki-67 is a nuclear antigen widely used in routine pathologic analyses as a tumor cell proliferation marker for lung cancer. However, Ki-67 expression analyses using immunohistochemistry (IHC) are invasive and frequently influenced by tissue sampling quality. In this study, we assessed the feasibility of noninvasive magnetic resonance imaging (MRI) in predicting the Ki-67 labeling indices (LIs). A total of 51 lung cancer patients, including 42 non-small cell lung cancer (NSCLC) cases and nine small cell lung cancer (SCLC) cases, were enrolled in this study. Quantitative MRI parameters from conventional diffusion-weighted imaging (DWI), intravoxel incoherent motion (IVIM), and diffusion kurtosis imaging (DKI) were obtained, and their correlations with tumor tissue Ki-67 expression were analyzed. We found that the true diffusion coefficient (D value) from IVIM was negatively correlated with Ki-67 expression (Spearman r = -0.76, P < 0.001). The D values in the high Ki-67 group were significantly lower than those in the low Ki-67 group (0.90 ± 0.21 × 10^-3 mm²/s vs. 1.22 ± 0.30 × 10^-3 mm²/s). Among three MRI techniques used, D values from IVIM showed the best performance for distinguishing the high Ki-67 group from low Ki-67 group in receiver operating characteristic (ROC) analysis with an area under the ROC curve (AUROC) of 0.85 (95% CI: 0.73-0.97, P < 0.05). Moreover, D values performed well for differentiating SCLC from NSCLC with an AUROC of 0.82 (95% CI: 0.68-0.90), Youden index of 0.72, and F1 score of 0.81. In conclusion, D values were negatively correlated with Ki-67 expression in lung cancer tissues and can be used to distinguish high from low proliferation statuses, as well as SCLC from NSCLC.

Multiple Testing, Cut-Point Optimization, and Signs of Publication Bias in Prognostic FDG-PET Imaging Studies of Head and Neck and Lung Cancer: A Review and Meta-Analysis

Positron emission tomography (PET) imaging with 2-deoxy-2-[¹⁸F]-fluorodeoxyglucose (FDG) was proposed as prognostic marker in radiotherapy. Various uptake metrics and cut points were used, potentially leading to inflated effect estimates. Here, we performed a meta-analysis and systematic review of the prognostic value of pretreatment FDG–PET in head and neck squamous cell carcinoma (HNSCC) and non-small cell lung cancer (NSCLC), with tests for publication bias. Hazard ratio (HR) for overall survival (OS), disease free survival (DFS), and local control was extracted or derived from the 57 studies included. Test for publication bias was performed, and the number of statistical tests and cut-point optimizations were registered. Eggers regression related to correlation of SUVmax with OS/DFS yielded p = 0.08/p = 0.02 for HNSCC and p < 0.001/p = 0.014 for NSCLC. No outcomes showed significant correlation with SUVmax, when adjusting for publication bias effect, whereas all four showed a correlation in the conventional meta-analysis. The number of statistical tests and cut points were high with no indication of improvement over time. Our analysis showed significant evidence of publication bias leading to inflated estimates of the prognostic value of SUVmax. We suggest that improved management of these complexities, including predefined statistical analysis plans, are critical for a reliable assessment of FDG–PET.

The associations among quantitative spectral CT parameters, Ki-67 expression levels and EGFR mutation status in NSCLC

Dual-energy spectral computed tomography (DESCT) is based on fast switching between high and low voltages from view to view to obtain dual-energy imaging data, and it can generate monochromatic image sets, iodine-based material decomposition images and spectral CT curves. Quantitative spectral CT parameters may be valuable for reflecting Ki-67 expression and EGFR mutation status in non-small-cell lung cancer (NSCLC). We investigated the associations among the quantitative parameters generated in DESCT and Ki-67 expression and EGFR mutation in NSCLC. We studied sixty-five NSCLC patients with preoperative DESCT scans, and their specimens underwent Ki-67 and EGFR evaluations. Statistical analyses were performed to identify the spectral CT parameters for the diagnosis of Ki-67 expression and EGFR mutation status. We found that tumour grade and the slope of the spectral CT curve in the venous phase were the independent factors influencing the Ki-67 expression level, and the area under the curve (AUC) of the slope of the spectral CT curve in the venous phase in the receiver operating characteristic analysis for distinguishing different Ki-67 expression levels was 0.901. Smoking status and the normalized iodine concentration in the venous phase were independent factors influencing EGFR mutation, and the AUC of the two-factor combination for predicting the presence of EGFR mutation was 0.807. These results show that spectral CT parameters may be useful for predicting Ki-67 expression and the presence of EGFR mutation in NSCLC.

The metabolic clinical risk score as a new prognostic model for surgical decision-making in patients with colorectal liver metastases

BACKGROUND AND OBJECTIVES

Selection for surgery in patients with colorectal liver metastases (CRLM) remains inaccurate. We evaluated if CRLM baseline metabolic characteristics, assessed by [18]F-fluorodeoxyglucose-positron emission tomography/computed tomography (¹⁸ FDG-PET/CT), could predict postoperative outcomes.

METHODS

In a retrospective series of patients undergoing surgery for CRLM, we defined two groups: the long-term survival (LTS) and early relapse (ER) groups, where the postoperative recurrence-free survivals were ≥5 years or <1 year, respectively. We analyzed the patients in whom baseline ¹⁸ FDG-PET/CT was available. Clinicopathologic parameters, clinical risk score (CRS), and baseline ¹⁸ FDG-PET/CT characteristics were compared between LTS and ER groups. A metabolic CRS (mCRS) was implemented, adding one point to the standard five-point CRS when the highest tumor standardized uptake values (SUV_max )/normal liver mean SUV (SUV_mean(liver) ) ratios were >4.3, defining low- and high-risk mCRS by scores of 0 to 2 and 3 to 6, respectively.

RESULTS

From a series of 450 patients operated for CRLM (mean follow-up of 58 months), we included for analysis 23 and 30 patients in the LTS and ER groups, respectively. Clinicopathologic parameters and CRS were similar in the LTS and ER groups. Median SUV_max /SUV_mean(liver) ratios were higher in ER vs LTS patients (4.2 and 2.8, P = .008, respectively). mCRS was increased in ER patients (P = .024); 61% of LTS patients had low-risk mCRS and 73% of the ER patients had high-risk mCRS (P = .023).

CONCLUSIONS

¹⁸ FDG-PET/CT characteristics combined with traditional CRS may represent a new tool to improve selection for surgery in patients with CRLM.

Associations between GLUT expression and SUV values derived from FDG-PET in different tumors-A systematic review and meta analysis

Purpose

Fluorodeoxyglucose-Positron-emission tomography (FDG-PET), quantified by standardized uptake values (SUV), is one of the most used functional imaging modality in clinical routine. It is widely acknowledged to be strongly associated with Glucose-transporter family (GLUT)-expression in tumors, which mediates the glucose uptake into cells. The present systematic review sought to elucidate the association between GLUT 1 and 3 expression with SUV values in various tumors.

Methods

MEDLINE library was screened for associations between FDG-PET parameters and GLUT correlation cancer up to October 2018.

Results

There were 53 studies comprising 2291 patients involving GLUT 1 expression and 11 studies comprising 405 patients of GLUT 3 expression. The pooled correlation coefficient for GLUT 1 was r = 0.46 (95% CI 0.40–0.52), for GLUT 3 was r = 0.35 (95%CI 0.24–0.46). Thereafter, subgroup analyses were performed. The highest correlation coefficient for GLUT 1 was found in pancreatic cancer r = 0.60 (95%CI 0.46–0.75), the lowest was identified in colorectal cancer with r = 0.21 (95% CI -0.57–0.09).

Conclusion

An overall only moderate association was found between GLUT 1 expression and SUV values derived from FDG-PET. The correlation coefficient with GLUT 3 was weaker. Presumably, the underlying mechanisms of glucose hypermetabolism in tumors are more complex and not solely depended on the GLUT expression.

Fluorine-18-fluorodeoxyglucose-positron emission tomography evaluation in metastatic bone lesions in lung cancer: Possible prediction of pain and skeletal-related events

Background

Fluorine‐18‐fluorodeoxyglucose‐positron emission tomography (FDG‐PET) uptake in primary lesions has been well studied, but little information is available about metastatic bone lesions in patients with lung cancer. The present study was performed to evaluate the relationships between metastatic bone FDG uptake and clinical parameters in patients with lung cancer.

Methods

FDG uptake was evaluated as the maximum standardized uptake (SUVmax) value of each targeted bone lesion, and the bone to primary lesion ratio of SUVmax (B/P ratio) was calculated. Forty‐nine patients (27 men and 22 women) with a diagnosis of lung cancer (small cell lung cancer [SCLC], n = 7; non‐small cell lung cancer [NSCLC], n = 42) with bone metastasis, and a total of 185 bone metastatic lesions were evaluated.

Results

The SUVmax in bone and the B/P ratio were significantly higher in patients with pain and subsequent development of skeletal‐related events than in those without pain or skeletal‐related events, respectively. In addition, the SUVmax in metastatic bone lesions and the B/P ratio in SCLC were significantly lower than those in NSCLC, despite similar FDG uptake in the primary tumor.

Conclusion

Our findings suggest that FDG‐PET evaluation in metastatic bone lesions could be useful to predict initial pain and subsequent clinical outcomes of local bone status in initially diagnosed lung cancer patients with bone metastasis. In addition, our results suggest that there could be histological differences in the biological activity of bone metastatic lesions in lung cancer, especially between SCLC and NSCLC.

The assessment of correlation and prognosis among 18F-FDG uptake parameters, Glut1, pStat1 and pStat3 in surgically resected non-small cell lung cancer patients

Introduction

To assess the correlation among ¹⁸F-FDG uptake, Glut1, pStat1 and pStat3, and to investigate the relationship between the prognosis and ¹⁸F-FDG uptake and these molecular markers in surgically resected non-small cell lung cancer (NSCLC) patients.

Results

Knockdown of Glut1 led to a significant increase in pStat1 expression. Glut1 expression positively correlated with the SUVmax, SUVmean, and TLG significantly (P<0.001). pStat3 expression negatively correlated with all PET parameters significantly (P<0.001). pStat1 had positive weak correlations with the SUVmax and SUVmean. All PET parameters and Glut1 were significantly associated with DFS (P<0.05). TLG, MTV, Glut1 and pStat1 were significantly associated with OS (P<0.05).

Conclusion

pStat3 and Glut1 may be associated with ¹⁸F-FDG uptake mechanism. TLG, MTV, and Glut1 may be independent prognostic factors.

Methods

The SUVmax, SUVmean, MTV and TLG of primary lesions were calculated in 140 patients. The expressions of Glut1 and Stat pathway proteins in NSCLC cell lines were examined by immune blots. Excised tumor tissue was analyzed by immunohistochemistry. OS and DFS were evaluated by the Kaplan-Meier method. The difference in survival between subgroups was analyzed by log-rank test. The prognostic significance of clinicopathological, molecular and PET parameters was assessed by Cox proportional hazard regression analysis.

Standardized Uptake Values Derived from 18F-FDG PET May Predict Lung Cancer Microvessel Density and Expression of KI 67, VEGF, and HIF-1α but Not Expression of Cyclin D1, PCNA, EGFR, PD L1, and p53

Background

Our purpose was to provide data regarding relationships between ¹⁸F-FDG PET and histopathological parameters in lung cancer.

Methods

MEDLINE library was screened for associations between PET parameters and histopathological features in lung cancer up to December 2017. Only papers containing correlation coefficients between PET parameters and histopathological findings were acquired for the analysis. Overall, 40 publications were identified.

Results

Associations between SUV and KI 67 were reported in 23 studies (1362 patients). The pooled correlation coefficient was 0.44. In 2 studies (180 patients), relationships between SUV and expression of cyclin D1 were analyzed (pooled correlation coefficient = 0.05). Correlation between SUV and HIF-1α was investigated in 3 studies (288 patients), and the pooled correlation coefficient was 0.42. In 5 studies (310 patients), associations between SUV and MVD were investigated (pooled correlation coefficient = 0.54). In 6 studies (305 patients), relationships between SUV and p53 were analyzed (pooled correlation coefficient = 0.30). In 6 studies (415 patients), associations between SUV and VEGF expression were investigated (pooled correlation coefficient = 0.44). In 5 studies (202 patients), associations between SUV and PCNA were investigated (pooled correlation coefficient = 0.32). In 3 studies (718 patients), associations between SUV and expression of PD L1 were analyzed (pooled correlation coefficient = 0.36). Finally, in 5 studies (409 patients), associations between SUV and EGFR were investigated (pooled correlation coefficient = 0.38).

Conclusion

SUV may predict microvessel density and expression of VEGF, KI 67, and HIF-1α in lung cancer.

Genomic Characterization of Lung Cancer and Its Impact on the Use and Timing of PET in Therapeutic Response Assessment

Significant advances in understanding the genomic landscape of non-small cell lung cancer (NSCLC) together with the coupling discovery of key oncogenic drivers and the development of effective targeted and immunotherapeutic agents have revolutionized the management of this malignancy. Although these therapies have resulted in improved outcomes for a subgroup of patients, their benefit may not necessarily be reflected by conventional response assessment criteria, because these therapeutic agents differ in their mechanism of action and response time compared with cytotoxic chemotherapy. Here the authors review available therapies in NSCLC and the utility of PET in therapeutic response assessment.

Metabolic characteristics of programmed cell death-ligand 1-expressing lung cancer on 18 F-fluorodeoxyglucose positron emission tomography/computed tomography

Programmed cell death‐1 (PD‐1) and programmed cell death‐ligand 1 (PD‐L1) have been identified as novel targets of immunotherapy of lung cancer. In present study, we evaluated the metabolic characteristics of lung cancer by using ¹⁸F‐fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F‐FDG PET/CT) with regard to PD‐L1 protein expression. PD‐L1 protein expression was evaluated by immunohistochemistry with the antibody clone SP142 in 579 surgically resected primary lung cancer patients. Cases with less than 5% tumor membrane staining were considered negative. We examined the association between the frequency of PD‐L1 protein expression and the maximum standardized uptake value (SUVmax) in preoperative ¹⁸F‐FDG PET/CT. The cut‐off values for SUVmax were determined by receiver operating characteristic curve analyses. The SUVmax was significantly higher in nonsmall cell lung cancer (NSCLC) patients with PD‐L1 protein expression compared with those without PD‐L1 protein expression (P < 0.0001). However, there was no correlation between SUVmax and PD‐L1 protein expression in patients with neuroendocrine tumors (P = 0.6545). Multivariate analysis revealed that smoking, the presence of pleural invasion, and high SUVmax were independent predictors of PD‐L1 positivity. PD‐L1‐expressing NSCLC had a high glucose metabolism. The SUVmax in preoperative ¹⁸F‐FDG PET/CT was a predictor of PD‐L1 protein expression in patients with NSCLC.

Glycolysis-related protein expression in thyroid cancer

We aimed to demonstrate the differences in the expression of glucose metabolism-related proteins according to the thyroid cancer subtypes and investigate the implications of these differences. A total of 566 thyroid cancer patients, including 342 cases of papillary thyroid carcinoma, 112 cases of follicular carcinoma, 70 cases of medullary carcinoma, 23 cases of poorly differentiated carcinoma, 19 cases of anaplastic carcinoma, and 152 cases of follicular adenoma, were enrolled in the study. Immunohistochemical staining for glucose transporter 1, hexokinase II, carbonic anhydrase IX, and monocarbonylate transporter 4 was performed, and the relationship between immunoreactivity and clinicopathologic parameters was analyzed. Glucose transporter 1 and tumoral monocarbonylate transporter 4 expression levels were shown to be the highest in anaplastic carcinoma, and medullary carcinoma showed the highest carbonic anhydrase IX and lowest hexokinase II levels compared with other subtypes. Stromal expression of monocarbonylate transporter 4 was observed in papillary thyroid carcinoma and anaplastic carcinoma samples. Conventional papillary thyroid carcinoma tumors expressed higher levels of glucose transporter 1, and tumoral and stromal monocarbonylate transporter 4, than the follicular variant, which showed a higher expression of carbonic anhydrase IX. Papillary thyroid carcinoma samples with BRAF V600E mutation were shown to have higher glucose transporter 1, hexokinase II, carbonic anhydrase IX, and tumoral monocarbonylate transporter 4 expression levels. Univariate analysis showed that papillary thyroid carcinoma cases with glucose transporter 1 positivity had shorter overall survival, patients with medullary carcinoma and hexokinase II positivity were shown to have a shorter disease-free survival and overall survival, and tumoral monocarbonylate transporter 4 positivity was associated with shorter overall survival compared with papillary thyroid carcinoma patients with negativity for each marker. Disease-free survival and overall survival of patients with poorly differentiated carcinoma were shown to be significantly decreased when glucose transporter 1 and tumoral monocarbonylate transporter 4 are expressed. We demonstrated that the expression levels of glycolysis-related proteins differ between thyroid cancer subtypes and are correlated with poorer prognosis, depending on the subtype.

Optimal delivery of follow-up care following pulmonary lobectomy for lung cancer

Introduction

The rationale for oncologic surveillance following pulmonary lobectomy is to detect recurrent disease or a second primary lung cancer early enough so that an intervention can increase survival and/or improve quality of life. Therefore, we reviewed literature for international guidelines and reorganized these useful factors associated with non-small-cell lung cancer (NSCLC) recurrence as remedies in postoperative follow-up.

Method

The population of interest for this review was patients who had been treated with complete resection for primary NSCLC and were in follow-up.

Result

Guidelines on follow-up care for NSCLC vary internationally. Because of the production of progressive medical modalities, the current follow-up care should be corrected.

Conclusion

The specific follow-up schedule for computed tomography imaging may be more or less frequent, depending upon risk factors for recurrence. Many different predictors of postoperative recurrence may help to optimize the patient selection for specified surveillance guidelines and personalized adjuvant therapies to prevent possibly occult micrometastases and to get a better outcome.

Correlation of HIF-1α/HIF-2α expression with FDG uptake in lung adenocarcinoma

OBJECTIVES

Hypoxia is a key element involved in the development and progression of tumors. HIF-1α may transiently induce and mediate the response to acute and severe hypoxia, while HIF-2α may induce a longer response and may control the response to chronic and moderate hypoxia. Hypoxia increases the cellular uptake of FDG. Therefore, HIF may play an important role in the process of the cellular uptake of FDG. The aim of this study was to compare HIF-1α/HIF-2α expression with FDG uptake, Glut-1 expression, and prognosis in the patients with lung adenocarcinoma and to investigate the role of HIF-1α/HIF-2α in the uptake of FDG in lung adenocarcinoma.

METHODS

In the current work, we compared the immunohistochemical expression of HIF-1α and HIF-2α in surgical specimens of 44 patients with lung adenocarcinoma. The relationships between HIF-α expression and Glut-1 expression, FDG uptake, and clinicopathological factors, including prognosis, were analyzed.

RESULTS

There was a marginal association between HIF-1α and HIF-2α expressions (P = 0.076). We found a significant correlation between HIF-2α expression and FDG uptake (P = 0.0001). HIF-1α expression showed a marginal association with FDG uptake (P = 0.066). FDG uptake correlated more significantly with HIF-2α expression than with HIF-1α expression. A significant correlation was noticed between Glut-1 expression and both HIF-1α and HIF-2α expressions (P = 0.005 and P = 0.003, respectively). Univariate analysis of disease-free survival demonstrated that FDG uptake and HIF-2α expression, but not HIF-1α expression, were related to recurrence (P < 0.0001).

CONCLUSION

FDG uptake correlated more significantly with HIF-2α expression than with HIF-1α expression, and both FDG uptake and HIF-2α expression, but not HIF-1α expression was correlated with post-operative recurrence in the patients with lung adenocarcinoma. These results suggest that both FDG uptake and HIF-2α expression may represent a more aggressive phenotype and that HIF-2α may play a more important role than HIF-1α in the uptake of FDG in lung adenocarcinoma.

Prognostic Significance of Intratumoral Metabolic Heterogeneity on 18F-FDG PET/CT in Pathological N0 Non-Small Cell Lung Cancer

PURPOSE

The aim of the study was to evaluate the prognostic significance of intratumoral metabolic heterogeneity on pretreatment F-FDG PET/CT in patients with lung cancer who were pathologically N0 (pN0) after curative surgical resection.

METHODS

We examined 119 patients (M/F = 79/40; mean age, 64.6 ± 9.0 years) who had undergone pretreatment F-FDG PET/CT and were diagnosed as pN0 after curative surgery for adenocarcinoma (ADC; n = 67) or squamous cell carcinoma (SQCC; n = 52). Heterogeneity factor (HF) and other metabolic parameters (SUVmax, metabolic tumor volume [MTV] and total lesion glycolysis [TLG]) for the primary lesions were measured, and the results were analyzed for recurrence. The HF, defined as the derivative of the volume-threshold function from 20% to 80%, was computed for primary lesions. Univariate and multivariate analyses for recurrence were performed using the Kaplan-Meier method and using the Cox proportional hazards model.

RESULTS

SUVmax, MTV, TLG, and HF were statistically different between patients with ADC and SQCC. Forty-one (34.5%) of 119 patients experienced recurrence (ADC, 25/67 = 37.3% vs. SQCC, 16/52 = 30.8%). Results of univariate analysis indicate that SUVmax, MTV, TLG, and HF in ADC and TLG and HF in SQCC were predictors for recurrence. After adjusting for sex, age, and histological grade in multivariate analysis, high SUVmax, MTV, TLG, and HF in ADC exhibited an association with increased risk of recurrence.

CONCLUSIONS

Metabolic parameters and heterogeneity of primary tumor on pretreatment F-FDG PET/CT can predict recurrence in pN0 NSCLC patients of ADC type who have undergone curative surgery but not in patients of SQCC type.

Association between histopathological subtype, 18F-fluorodeoxyglucose uptake and epidermal growth factor receptor mutations in lung adenocarcinoma

The aim of the present study was to investigate the association between histopathological subtypes, epidermal growth factor receptor (EGFR) mutations and ¹⁸F-fluorodeoxyglucose (FDG) uptake in patients with lung adenocarcinoma (ADC). The cases of 97 patients with lung ADC who underwent ¹⁸F-FDG positron emission tomography-computed tomography prior to surgical resection were retrospectively reviewed. The patients were stratified according to the International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society (IASLC/ATS/ERS) classification, and graded using a histopathological scoring system. EGFR mutations were identified. Clinicopathological characteristics associated with EGFR mutation status were evaluated using univariate and multivariate analyses. EGFR mutation was identified in 45.4% of the patients and was associated with gender, smoking history, maximum standardized uptake value (SUVmax) and histopathological score. ADC patients with a low SUVmax were more likely to exhibit EGFR mutations compared with patients with a high SUVmax (P=0.018). Patients with a lower histopathological score possessed a significantly lower SUVmax compared with patients with a higher score (P<0.001). Furthermore, the histopathological score and smoking history of the patients were identified to be independent predictors for EGFR mutations, according to multivariate logistic regression analysis. In conclusion, SUVmax and EGFR mutations were associated with lung ADC patients stratified according to the IASLC/ATS/ERS classification. Overall, SUVmax has the potential to be a useful marker in stratifying pre-operative patients with lung ADC and identifying EGFR mutations.

Correlation between Semi-Quantitative (18)F-FDG PET/CT Parameters and Ki-67 Expression in Small Cell Lung Cancer

PURPOSE

The aim of this study was to evaluate the relationship between semiquantitative parameters on (18)F-FDG PET/CT including maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) and the expression level of Ki-67 in small-cell lung cancer (SCLC).

METHODS

Ninety-four consecutive patients with SCLC were enrolled in this study. They underwent (18)F-FDG PET/CT for initial evaluation of SCLC, and we measured SUVmax, avgSUVmean, MTVsum, and TLGtotal on (18)F-FDG PET/CT images. The protein expression of Ki-67 was examined by immunohistochemical staining.

RESULTS

Significant correlations were found between the MTVsum and Ki-67 labeling index (r = 0.254, p = 0.014) and the TLGtotal and Ki-67 labeling index (r = 0.239, p = 0.020). No correlation was found between the SUVmax and Ki-67 labeling index (r = 0.116, p = 0.264) and the avgSUVmean and Ki-67 labeling index (r = 0.031, p = 0.770). Dividing the Ki-67 expression level into three categories, it was suggested that increasing Ki-67 expression level caused a stepwise increase in the MTVsum and TLGtotal. (p = 0.028 and 0.039, respectively), but not the SUVmax and avgSUVmean (p = 0.526 and 0.729, respectively).

CONCLUSION

In conclusion, the volume-based parameters of (18)F-FDG PET/CT correlate with immunohistochemical staining of Ki-67 in SCLC. Measurement of the MTVsum and TLGtotal by (18)F-FDG PET/CT might be a simple, noninvasive, and useful method to determine the proliferative potential of cancer cells.

Integrating Tumor and Stromal Gene Expression Signatures With Clinical Indices for Survival Stratification of Early-Stage Non-Small Cell Lung Cancer

BACKGROUND

Accurate survival stratification in early-stage non-small cell lung cancer (NSCLC) could inform the use of adjuvant therapy. We developed a clinically implementable mortality risk score incorporating distinct tumor microenvironmental gene expression signatures and clinical variables.

METHODS

Gene expression profiles from 1106 nonsquamous NSCLCs were used for generation and internal validation of a nine-gene molecular prognostic index (MPI). A quantitative polymerase chain reaction (qPCR) assay was developed and validated on an independent cohort of formalin-fixed paraffin-embedded (FFPE) tissues (n = 98). A prognostic score using clinical variables was generated using Surveillance, Epidemiology, and End Results data and combined with the MPI. All statistical tests for survival were two-sided.

RESULTS

The MPI stratified stage I patients into prognostic categories in three microarray and one FFPE qPCR validation cohorts (HR = 2.99, 95% CI = 1.55 to 5.76, P < .001 in stage IA patients of the largest microarray validation cohort; HR = 3.95, 95% CI = 1.24 to 12.64, P = .01 in stage IA of the qPCR cohort). Prognostic genes were expressed in distinct tumor cell subpopulations, and genes implicated in proliferation and stem cells portended poor outcomes, while genes involved in normal lung differentiation and immune infiltration were associated with superior survival. Integrating the MPI with clinical variables conferred greatest prognostic power (HR = 3.43, 95% CI = 2.18 to 5.39, P < .001 in stage I patients of the largest microarray cohort; HR = 3.99, 95% CI = 1.67 to 9.56, P < .001 in stage I patients of the qPCR cohort). Finally, the MPI was prognostic irrespective of somatic alterations in EGFR, KRAS, TP53, and ALK.

CONCLUSION

The MPI incorporates genes expressed in the tumor and its microenvironment and can be implemented clinically using qPCR assays on FFPE tissues. A composite model integrating the MPI with clinical variables provides the most accurate risk stratification.

Clinical Correlation Between Tumor Maximal Standardized Uptake Value in Metabolic Imaging and Metastatic Tumor Characteristics in Advanced Non-small Cell Lung Cancer

This study aimed to elucidate whether the maximal standardized uptake value (SUVmax) of primary tumors in metabolic imaging correlated with pathological or metastatic characteristics and whether it was prognostic in stage IV nonsmall cell lung cancer (NSCLC).We retrospectively reviewed the medical records of 412 eligible patients between June 2007 and January 2013. All enrolled patients fulfilled the following criteria: they were newly diagnosed with stage IV NSCLC without any previous treatment and had undergone a systemic evaluation, including 18(F)-Fluoro-2-deoxyglucose positron emission tomography/computed tomography, to assess synchronous metastatic sites. Patient and tumor characteristics were analyzed, and clinical correlations between SUVmax and metastatic features were investigated.The median age of the study population was 65 years (range, 30-94), and 259 (62.9%) patients were male. The median SUVmax was statistically higher in males, in tumors with squamous cell histology, and in poorly differentiated tumors. Multivariate logistic regression analysis revealed that SUVmax ≥ 11.4 (top 30 percentiles) were significantly correlated with positive lymph node status (odds ratio [OR] 3.473), abdomen/pelvis metastasis (OR 1.949), and the absence of bone metastasis (OR 0.399) in the subgroup of nonsquamous NSCLC (n = 343). In Kaplan-Meier survival analysis, overall survival was significantly lower among cohorts with high SUVmax (≥11.4) than with low SUVmax (<11.4) (P < 0.001, median 7.4 months vs 12.1 months).The tumors with different SUVmax have distinctive metastatic and biological features in stage IV NSCLC. The underlying mechanisms of this unique metabolic biology need to be resolved in future studies.

Assessment of cell proliferation in renal cell carcinoma using dual-phase 18F-fluorodeoxyglucose PET/CT

The present study aimed to examine the association between ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) uptake and cell proliferation markers; in addition, the correlation between ¹⁸F-FDG uptake and biological characteristic in patients with renal cell carcinoma (RCC) was investigated using dual-phase ¹⁸F-FDG-positron emission tomography/computed tomography (PET/CT). Dual-phase ¹⁸F-FDG PET/CT was performed on 31 RCC patients and the maximum standardized uptake values at 1 h (SUV1) and 2 h (SUV2) as well as the retention index (RI; %) in the primary tumors were calculated. Monoclonal antibodies for Ki-67, minichromosome maintenance 2 (MCM2) and topoisomerase II α (topo II α) were used to assess the expression levels of their respective proteins in excised tumor tissue using immunohistochemistry. The results demonstrated that RI and SUV2 in patients with Stage I/II + grade 1 (G1) RCC were significantly decreased compared with all patients with other stages/grades (RI, P=0.0065; SUV2, P=0.043); in addition, significantly increased uptake and RI were detected in patients with metastases compared with patients without metastases (SUV1, P=0.029; SUV2, P=0.0003; RI, P<0.001). All proliferation markers significantly correlated with RI (Ki-67, r=0.501, P=0.004; MCM2, r=0.359, P=0.047; topo II α, r=0.402, P=0.024), while SUV1 and SUV2 correlated with Ki-67 only. In conclusion, the results of the present study demonstrated that dual-phase ¹⁸F-FDG-PET/CT was more useful for predicting cell proliferation in RCC compared with single-phase imaging alone. However, follow-ups are required in order to determine whether dual-phase ¹⁸F-FDG-PET/CT provides independent prognostic information.

Correlation between the Uptake of 18F-Fluorodeoxyglucose (18F-FDG) and the Expression of Proliferation-Associated Antigen Ki-67 in Cancer Patients: A Meta-Analysis

Objective

To study the correlation between ¹⁸F-FDG uptake and cell proliferation in cancer patients by meta-analysis of published articles.

Methods

We searched PubMed (MEDLINE included), EMBASE, and Cochrane Database of Systematic Review, and selected research articles on the relationship between ¹⁸F-FDG uptake and Ki-67 expression (published between August 1, 1994-August 1, 2014), according to the literature inclusion and exclusion criteria. The publishing language was limited to English. The quality of included articles was evaluated according to the Quality Assessment of Diagnosis Accuracy Studies-2 (QUADAS-2). The correlation coefficient (r) was extracted from the included articles and processed by Fisher's r-to-z transformation. The combined correlation coefficient (r) and the 95% confidence interval (CI) were calculated with STATA 11.0 software under a random-effects model. Begg's test was used to analyze the existence of publication bias and draw funnel plot, and the sources of heterogeneity were explored by sensitivity and subgroup analyses.

Results

According to the inclusion and exclusion criteria, 79 articles were finally included, including 81 studies involving a total of 3242 patients. All the studies had a combined r of 0.44 (95% CI, 0.41-0.46), but with a significant heterogeneity (I² = 80.9%, P<0.01). Subgroup analysis for different tumor types indicated that most subgroups showed a reduced heterogeneity. Malignant melanoma (n = 1) had the minimum correlation coefficient (-0.22) between ¹⁸F-FDG uptake and Ki-67 expression, while the thymic epithelial tumors (TETs; n = 2) showed the maximum correlation coefficient of 0.81. The analytical results confirmed that correlation between ¹⁸F-FDG uptake and Ki-67 expression was extremely significant in TETs, significant in gastrointestinal stromal tumors (GISTs), moderate in patients with lung, breast, bone and soft tissue, pancreatic, oral, thoracic, and uterine and ovarian cancers, average in brain, esophageal and colorectal cancers, and poor in head and neck, thyroid, gastric and malignant melanoma tumors. Subgroup analysis indicated that positron emission tomography (PET) or PET/CT imaging technology or Ki-67 and standardized uptake value (SUV) measurement technology did not significantly affect the results of r values, and Begg's test showed no significant publication bias.

Conclusion

In cancer patients, ¹⁸F-FDG uptake showed a moderate positive correlation with tumor cell proliferation. Different tumor types exhibited varied degree of correlation, and the correlation was significant in TETs and GSTs. However, our results need further validation by clinical trials with a large sample of different tumor types.

Adenosquamous carcinoma of the lung: CT, FDG PET, and clinicopathologic findings

PURPOSE

The aim of this study is to evaluate CT, FDG PET, and clinicopathologic features of the adenosquamous carcinoma of the lung (ASC).

PATIENTS AND METHODS

Twenty-six patients (M/F = 20:6; mean age, 65.0 years) who underwent surgical resection of ASC were included. The tumors were assessed in terms of size, location, morphologic characteristics, and maximum standardized uptake value (SUVmax) on CT and FDG PET. Proportion of adenocarcinoma was determined. The central and peripheral groups were compared. The differences in disease-free survival among the groups according to the observations were analyzed by Kaplan-Meier test for patients who underwent curative resection (n = 21).

RESULTS

Diameter was 3.8 ± 1.9 cm. Five tumors were located centrally (19.2%) and 21 tumors peripherally (80.8%). Internal low and heterogeneous attenuation was found in all patients. Margins were lobulated in 20 (80%) patients, spiculated in 23 (92%), and ill-defined in 23 (92%). SUVmax was 8.3 ± 3.9. Adenocarcinoma proportion was 33 ± 28%. Central ASC were larger than peripheral ASC (5.7 cm vs. 3.4 cm, P = 0.007). Only SUVmax >6.3 was a poor prognostic factor.

CONCLUSION

ASC was more commonly peripheral than central, and showed internal low and heterogeneous attenuation and possessed lobulated, spiculated, or ill-defined margin on CT. Mean SUVmax of ASC was 8.3 ± 3.9. Central ASC was larger than peripheral ASC. Except for tumor size, central ASC and peripheral ASC showed no significant differences in pathology, FDG PET, and survival. Higher SUVmax was a poor prognostic factor.

[18F]fluoro-2-deoxyglucose-positron emission tomography for the assessment of histopathological response after preoperative chemoradiotherapy in advanced oral squamous cell carcinoma

BACKGROUND

[(18)F]fluoro-2-deoxyglucose-positron emission tomography (FDG-PET) is widely used to evaluate tumor metabolic activity. The aim of this study was to evaluate the usefulness of FDG-PET in assessing the histopathological response to preoperative concurrent chemoradiotherapy (CRT) in patients with oral squamous cell carcinoma (OSCC).

METHODS

Forty-five patients with resectable advanced OSCC who had received preoperative CRT followed by tumor ablative surgery between January 2004 and December 2011 were included in the study. All patients underwent FDG-PET before and after preoperative CRT. The maximum standardized uptake value (SUVmax) before (pre-SUV) and after preoperative CRT (post-SUV) and the SUVmax reduction rate (ΔSUV %) were used to evaluate the response to preoperative CRT. Correlations among SUVmax, histopathological response, and expression of cancer antigen Ki-67 and hypoxia-inducible factor-1α (HIF-1α) were analyzed.

RESULTS

Preoperative CRT significantly reduced intratumoral FDG uptake (P < 0.001). The pre-SUV and post-SUV were significantly lower in patients with a pathological complete response (pCR) than in those with a non-pCR (pre-SUV P = 0.037; post-SUV P = 0.001). ΔSUV % was higher in patients with pCR than in those with non-pCR (P = 0.029). The pre-SUV was significantly correlated with Ki-67 and HIF-1α expression in pretreatment biopsy specimens (Ki-67 P = 0.046, R = 0.292; HIF-1α P = 0.007, R = 0.385). The expression of both Ki-67 and HIF-1α was significantly lower in patients with pCR than in those with non-pCR (Ki-67 P < 0.001; HIF-1α P < 0.001).

CONCLUSIONS

Low pre-SUV and post-SUV and high ΔSUV % may predict a good histopathological response to preoperative CRT. Ki-67 and HIF-1α expression in pretreatment biopsy specimens were predictors of histopathological response to preoperative CRT.

High FDG uptake predicts poorer survival in locally advanced nonsmall cell lung cancer patients undergoing curative radiotherapy, independently of tumor size

OBJECTIVES

Despite radical radiotherapy and chemotherapy (CT), the prognosis of locally advanced nonsmall cell lung cancer (NSCLC) is poor. New prognostic indicators are being looked forward to improve the survival. [18F]-fluorodeoxyglucose (FDG) uptake on PET/CT has been observed as a prognostic marker mainly in early-stage disease. Our aim was to examine the prognostic value of FDG uptake in locally advanced NSCLC.

MATERIALS AND METHODS

Between 2009 and 2011, 103 NSCLC patients underwent disease staging using FDG PET/CT before conformal radiotherapy. Thoracic radiation was administered at a daily fraction of 2 Gy. Total dose was prescribed according to the tumor response against CT. All patients underwent CT. Survival was estimated using the Kaplan-Meier method.

RESULTS

The median age of the patients was 59 years (range 39-83). The median follow-up time was 22.63 months (range 6-48.03 months). There was a statistically significant difference in overall survival (OS) between the low (<10.7) and high (≥10.7) standardized uptake value (SUVmax) groups (p = 0.006) on univariate analysis (3-year OS was 42% in the low (<10.7) and 23% in the high (≥10.7) SUVmax groups). On multivariate analysis with determining tumor size, tumor SUVmax provided additional significant prognostic information on OS (HR 1.046; 95 % CI 1.009-1.085, p = 0.015).

CONCLUSIONS

FDG uptake has predictive value in locally advanced NSCLC, independently of tumor size.

Use of high-resolution computed tomography and positron emission tomography/computed tomography in the management of stage IA adenocarcinoma

Preoperative determination of malignant behavior is critical in choosing suitable therapeutic strategies such as sublobar resection for patients with small lung cancers. The aim of present review was to evaluate high-resolution computed tomography and fluorodeoxyglucose-positron emission tomography/computed tomography as tools for management of clinical stage IA adenocarcinoma.

Regional PET/CT after water gastric inflation for evaluating loco-regional disease of gastric cancer

OBJECTIVE

We aimed to improve diagnostic accuracy of (18)F-fluoro-2-deoxyglucose (FDG) PET/CT for gastric cancer with water gastric inflation.

MATERIALS AND METHODS

44 gastric cancer patients (M:F=30:14, age ± std=62.1 ± 14.5 y) were enrolled before surgery. Fifty minutes after injection of FDG (0.14 mCi/kg body weight), whole body PET/CT was performed first and then regional PET/CT over gastric area was obtained 80 min post FDG injection after water gastric inflation. Diagnostic accuracies for loco-regional lesions were compared between whole body and regional PET/CT.

RESULTS

48 primary tumors (23 EGC and 25 AGC) and 348 LN stations (61 metastatic and 287 benign) in 44 patients were investigated. Primary tumor sensitivity of whole body PET/CT (50%=24/48) was significantly improved by regional PET/CT (75%=36/48, p<0.005). Sensitivity of whole body PET/CT (24.6%=15/61) for LN metastasis was also significantly improved by regional PET/CT (36.1%=22/61, p<0.01), whereas specificity of whole body PET/CT (99.3%=285/287) was not compromised by regional PET/CT (98.3%=282/287, p>0.05). Higher primary tumor FDG uptake in regional PET/CT indicated shorter progress-free survival (p=0.0003).

CONCLUSION

Diagnostic accuracy of whole body PET/CT for loco-regional disease of gastric cancer could be significantly improved by regional PET/CT after water gastric inflation and prognosis could be effectively predicted by primary tumor FDG uptake in regional PET/CT.

Non-small cell lung cancer evaluated with quantitative contrast-enhanced CT and PET-CT: net enhancement and standardized uptake values are related to tumour size and histology

Background

Personalized cancer therapy remains a challenge. In this context, we attempted to identify correlations between tumour angiogenesis, tumour metabolism and tumour cell type. To this aim, we used single=phase multidetector computed tomography (MDCT) and hybrid positron emission tomography-computed tomography (PET/CT) to determine whether net enhancement and standardized uptake value (SUVmax) were correlated with tumour size and cytology in patients affected by non-small cell lung cancer (NSCLC).

Material/Methods

Our study included 38 patients (30 men, 8 women, mean age 70) with a NSCLC measuring between 3 cm and 7 cm, using a 16-slice multidetector CT (Brilliance Philips) and with PET-CT (Biograph 16 Siemens Medical Solutions). The following lesion parameters were evaluated: maximum diameter, medium density before contrast injection (CT_pre), medium density after contrast injection (CT_{post average}), density in the most enhanced part of the lesion after contrast (CT_{post max}), net enhancement, SUVmax, age, and cytology. Correlation coefficient and p-value were computed for each pair of variables. In addition, correlations were computed for each pair of variables, and for all combinations of tumour types. We focused on subsets of data with more than 10 observations, and with correlation r>0.500 and p<0.05.

Results

A weak correlation (r=0.32; p=0.048) was found between SUVmax and tumour size; the correlation was stronger for masses larger than 31 mm (r=0.4515; p=0.0268). No other correlations were found among the variables examined.

Conclusions

Our data may have prognostic significance, and could lead to more appropriate surgical treatment and better treatment outcome.

Primary tumor PET/CT [¹⁸F]FDG uptake is an independent predictive factor for regional lymph node metastasis in patients with non-small cell lung cancer

Aim: To investigate the correlation between [¹⁸F]fluorodeoxyglucose (FDG) uptake in a primary tumor and pathologic N stages, and to further analyze the possible risk factors contributing to the regional lymph node metastasis. Patients and methods: Eighty patients with non-small cell lung cancer (NSCLC) who underwent positron emission tomography/computed tomography were enrolled in the study. The FDG uptake in the primary tumor was compared for the different N staging groups and further correlation was performed. The degree of FDG uptake in the primary tumor and other possible variables related to the incidence of lymph node metastasis were examined by univariate and logistic multivariate analysis. FDG uptake was quantitated using the maximum standardized uptake value (SUV_max). Results: Statistically significant differences were found in the SUV_max of the primary tumors among different N staging groups (F = 4.124, P = 0.023), and the correlation between them was also statistically significant (r = 0.438, P = 0.000). Univariate analysis showed that blood tumor markers, primary tumor size, histologic grade, and SUV_max of the primary tumor were significantly associated with lymph node involvement. Logistic multivariate analysis showed that blood tumor makers and SUV_max of primary tumor might be considered as significant predictive factors for lymph node metastasis in patients with NSCLC. Conclusion: Our results show that there is a significant relationship between the SUV_max of the primary tumor and the pathologic N stage of NSCLC. FDG uptake by the primary tumor may be an independent predictor of regional lymph node metastasis in patients with NSCLC.

18F-FDG PET/CT features of pulmonary sclerosing hemangioma

BACKGROUND

Pulmonary sclerosing hemangioma (PSH) has been reported to show increased FDG uptake and be potential false-positives on 18F-FDG PET/CT examination. However, it is still unclear whether the previously-reported high FDG uptake is a universal characteristic of PSH, and furthermore, there have been no investigations on what kind of radiologic or histologic features may have been related with its FDG uptake values.

PURPOSE

To investigate the 18F-FDG PET/CT features of pulmonary sclerosing hemangiomas (PSHs), and to evaluate the relating factors with their FDG uptake values.

MATERIAL AND METHODS

We identified 10 PSHs in eight patients who had a pathologic diagnosis and available antecedent 18F-FDG PET/CT images. 18F-FDG PET/CT images were investigated both qualitatively and quantitatively, along with their histopathologic features. Correlation between 18F-FDG PET features and radiologic as well as histopathologic features were also evaluated.

RESULTS

Mean diameter of the 10 PSHs in our study was 16.9 mm ± 6.26 (range 5-25 mm). Four tumors showed intense uptake, and four tumors showed moderate uptake on 18F-FDG PET/CT scans. In the remaining two tumors, there were no significant FDG uptakes. The SUVmax of tumors ranged from 0.60-4.7 (median 2.30; 2.51 ± 1.42), and was significantly correlated with the tumor size (r = 0.754, P = 0.012) and three out of four tumors ≥2 cm (75%) showed intense FDG uptake and their SUVmax values were greater than 2.5. Immunohistochemical results for GLUT-1, GLUT-4, and Ki-67 and other pathologic features were not correlated with the tumors' FDG uptake.

CONCLUSION

The majority of PSHs show increased FDG uptakes, and their SUVmax values are significantly correlated with their tumor size. PSH ≥2 cm can frequently be falsely interpreted as malignancy in FDG-PET/CT. Further studies with large study population are warranted to confirm our observations.

Monitoring the effects of bevacizumab beyond progression in a murine colorectal cancer model: a functional imaging approach

Clinical studies have shown that bevacizumab beyond progression to first line therapy is beneficial for overall survival in advanced stage colorectal cancer. We studied the utility of several functional imaging modalities to assess the efficacy of bevacizumab beyond progression (BBP). All BALB/c mice with s.c. LS174T xenografts were treated with capecitabine, oxaliplatin and bevacizumab combination therapy. Tumor volume was assessed using caliper measurements. Increase of 1.5 times the initial volume on two subsequent measurements, was considered progression. In half of the mice bevacizumab treatment was continued (n = 13) after progressive disease was established, while the others received saline injections (n = 12). Within 3 days after progression, multi-modal imaging was performed using FDG-PET, diffusion weighted imaging, T2* and dynamic contrast enhanced MRI. Measurements were repeated 7 and 10 days after the first measurements. Afterwards, tumors were analyzed for expression of carbonic anhydrase IX, glucose transporter 1, 9 F1 to stain the vasculature and Ki67 to assess proliferation. In the BBP group tumor growth after progression was reduced compared to the control group (p < 0.01). FDG-PET showed a trend towards lower FDG uptake in the BBP group (p = 0.08). DWI, T2* and DCE-MRI parameters were not significantly different between both groups. The immunohistochemical analyses showed higher CAIX-positive fraction (p < 0.01) and lower Ki67 expression (p = 0.06) in the BBP group. The relative vascular area was significantly lower in the BBP group (p = 0.03). GLUT-1 expression and vascular density did not significantly differ between both groups. Bevacizumab after progression resulted in significant changes in the tumor proliferation and microenvironment compared to discontinuation of bevacizumab. FDG-PET may be sensitive to BBP-induced effects.

Metabolic and metastatic characteristics of ALK-rearranged lung adenocarcinoma on FDG PET/CT

INTRODUCTION

ALK rearrangement in lung cancer has been identified as a novel molecular target in lung adenocarcinoma. In this study, we evaluated metabolic and metastatic features of lung adenocarcinoma by using FDG PET/CT, with regard to specific genotypes of ALK and EGFR mutation.

METHODS

Patients with lung adenocarcinoma initially diagnosed and examined with FDG PET/CT and molecular genotyping with biopsy specimen, from September 2009 to September 2011, were selected retrospectively. ALK fluorescence in situ hybridization and EGFR mutations were tested. Maximum standardized uptake value (SUVmax) and metastatic characteristics on FDG PET/CT were analyzed with regard to ALK and EGFR status.

RESULTS

Of the 331 lung adenocarcinoma patients, 18 were ALK positive (ALK(+)), 156 were EGFR mutation positive (EGFR(+)), and 157 were wild type (WT) for both ALK and EGFR mutation. The ALK(+) tumor showed significantly higher SUVmax and more common metastasis to lymph nodes and distant organs than those of other genotypes in overall patients (P<0.01). In a subgroup analysis of advanced stage (stage IIIb and IV), ALK(+) lung cancer showed significantly higher SUVmax (P<0.05) than EGFR(+) tumors. In another subgroup analysis of size matched groups, ALK(+) tumors showed significant difference in SUVmax, lymph node and distant metastasis (P<0.01), particularly in the moderate-sized tumors (1.5-3cm).

CONCLUSION

ALK-rearranged lung adenocarcinoma represents higher glucose metabolism and more rapid metastasis to lymph nodes or distant sites compared with those with EGFR mutation and wild type, which suggests more aggressive features of ALK rearrangement.

Clinical impact of ki-67 labeling index in non-small cell lung cancer

The ki-67 index is a marker of proliferation in malignant tumors. Studies from the period 2000 to 2012 on the prognostic and predictive value of ki-67 labeling index (LI) in non-small cell cancer (NSCLC) are reviewed. Twenty-eight studies reported on the prognostic value of ki-67 index with various endpoints. No consensus on the prognostic value of ki-67 LI was found among the published studies neither according to disease stage nor histological subtype. Comparison of studies is hampered by differences in patient populations, methodologies and cut-off values. Five studies explored the predictive value of ki-67 to chemotherapy and none revealed significant influence. Ki-67 index seems to be of prognostic influence in NSCLC although largely variable cut-off levels have been used in the various studies and standardization of methodology is required. The relative importance of ki-67 compared to newer biomarkers has not been explored. It is likely that a signature of several biomarkers in combination may be necessary to more sufficiently stratify patients to various treatment options than is currently possible, especially when it comes to the question of the optimal use of classical chemotherapy. A predictive impact of ki-67 to treatment in NSCLC remains unclear.

Potential role of FDG PET imaging in predicting metastatic potential and assessment of therapeutic response to neoadjuvant chemotherapy in Ewing sarcoma family of tumors

AIMS AND OBJECTIVES

The aim of this study was to retrospectively correlate FDG uptake in primary Ewing sarcoma family of tumors (ESFT) with tumor behavior, and to evaluate whether FDG PET can be used to predict response to neoadjuvant chemotherapy (NACT) in this patient group.

METHODS

Out of the total 54 patients of recently diagnosed ESFT who underwent pretreatment FDG PET imaging, group I included patients without metastasis at presentation (n = 34) and group II included those with metastasis at presentation (n = 20). Fourteen of these patients had undergone FDG PET after 4 cycles of induction chemotherapy and surgical resection of primary tumor. In this subgroup of 14 patients, maximum standardized uptake value (SUVmax) of primary tumor was estimated before and after 4 cycles of induction chemotherapy and was correlated with the histopathological response in terms of necrosis in the tumor specimen.

RESULTS

Mean SUVmax in the primary tumor in group I patients was 6.84 and in group II patients, it was 11.31. The difference between mean SUVmax of these 2 groups was significant by Wilcoxon test analysis, with P < 0.01. In group II patients, SUVmax in metastasis with maximum FDG uptake was consistently lower as compared with that of primary tumor. In subgroup of 14 patients, Pearson correlation analysis showed that percentage change in SUVmax of primary tumor correlated well with percentage necrosis on histopathological examination (P < 0.01).

CONCLUSION

FDG uptake in primary ESFT reflected its metastatic potential and hence the aggressive behavior. The significant correlation between change in metabolic activity of the primary tumor and histopathological response after neoadjuvant chemotherapy suggests that FDG PET may be an ideal noninvasive method to assess tumor behavior and response to therapy in ESFT.

Histological subtypes of lung adenocarcinoma have differential ¹⁸F-fluorodeoxyglucose uptakes on the positron emission tomography/computed tomography scan

INTRODUCTION

Previous studies have shown that lung squamous cell carcinoma has higher ¹⁸F-fluorodeoxyglucose (FDG) uptake on positron emission tomography (PET) than adenocarcinoma. We hypothesized that histological subtypes of lung adenocarcinoma were also different in ¹⁸F-FDG uptake.

METHODS

Patients who had preoperative PET/computed tomography (CT) scan and had undergone complete resection for lung adenocarcinoma between April 2007 and December 2009 were enrolled in this study. Because of the limitation of spatial resolution on PET/CT, tumors less than 1 cm were excluded for analysis. Two independent classification systems were used to categorize histological subtypes of adenocarcinoma; one was modified from the current World Health Organization classification and the other used the morphological features of the terminal respiratory unit (TRU). The maximal standardized uptake value (SUVmax) on PET/CT and the glucose transporter type 1 (GLUT-1) expression of the tumors were measured and correlated to the histology of lung adenocarcinoma.

RESULTS

One hundred fifty-two patients with 153 primary lung adenocarcinomas were included. There was a significant difference in SUVmax among different histological subtypes. Namely, solid predominant adenocarcinomas had significantly higher SUVmax than those with other predominant histology (p < 0.001), and TRU-type adenocarcinomas had significantly lower SUVmax than non-TRU-type adenocarcinomas (p < 0.001). Consistently, GLUT-1 expression was higher in tumors with a solid growth pattern than those without (p < 0.001) and in tumors with non-TRU type than TRU type (p < 0.001).

CONCLUSIONS

The histological subtypes of lung adenocarcinomas differ in GLUT-1 expression and ¹⁸F-FDG uptake on the PET/CT scan, suggesting that histological subtyping not only has morphological but also biological implications.

Differences in metabolism between adeno- and squamous cell non-small cell lung carcinomas: spatial distribution and prognostic value of GLUT1 and MCT4

BACKGROUND

Hypoxia leads to changes in tumor cell metabolism such as increased glycolysis. In this study, we examined the spatial distribution of the glycolysis and hypoxia related markers glucose transporter 1 (GLUT1) and monocarboxylate transporter 4 (MCT4) expression in relation to the vasculature in stage I, II and resectable stage IIIA NSCLC. Furthermore, associations of these markers with survival were investigated.

METHODS

GLUT1 and MCT4 expression were determined in 90 NSCLC fresh frozen biopsies using immunohistochemical techniques and a computerized image analysis system. Markers were analyzed for adenocarcinomas (n=41) and squamous cell carcinomas (n=34) separately. Eighty-four patients were retrospectively evaluated for relapse and survival.

RESULTS

Squamous cell carcinomas demonstrated higher GLUT1 expression, relative to adenocarcinomas. Also, in squamous cell carcinomas, GLUT1 and MCT4 expression increased with increasing distance from the vasculature, whereas in adenocarcinomas upregulation of MCT4 was already found at closer distance from vessels. In adenocarcinomas, high GLUT1 expression correlated with a poor differentiation grade and positive lymph nodes at diagnosis. High GLUT1 plus high MCT4 expression was associated with a poor disease-specific survival in only adenocarcinomas (p=0.032).

CONCLUSION

Analysis of GLUT1 and MCT4 expression on the histological level suggested a different metabolism for adenocarcinomas and squamous cell carcinomas. Likely, adenocarcinomas rely mainly on aerobic glycolysis for ATP production, whereas the behavior of squamous cell carcinomas is more physiologically, i.e. mitochondrial oxidation with anaerobic glycolysis under hypoxic conditions. High GLUT1 plus high MCT4 expression indicated an aggressive tumor behavior in adenocarcinomas. This subgroup of tumors may benefit from new treatment approaches, such as MCT4 inhibitors. Since this study has an exploratory character, our results warrant further investigation and need independent validation.

Difference in prognostic significance of maximum standardized uptake value on [18F]-fluoro-2-deoxyglucose positron emission tomography between adenocarcinoma and squamous cell carcinoma of the lung

OBJECTIVE

This study evaluates the prognostic significance of [18F]-fluoro-2-deoxyglucose positron emission tomography/computed tomography findings according to histological subtypes in patients with completely resected non-small cell lung cancer.

METHODS

We examined 176 consecutive patients who had undergone preoperative [18F]-fluoro-2-deoxyglucose-positron emission tomography/computed tomography imaging and curative surgical resection for adenocarcinoma (n = 132) or squamous cell carcinoma (n = 44). Maximum standardized uptake values for the primary lesions in all patients were calculated as the [18F]-fluoro-2-deoxyglucose uptake and the surgical results were analyzed.

RESULTS

The median values of maximum standardized uptake value for the primary tumors were 2.60 in patients with adenocarcinoma and 6.95 in patients with squamous cell carcinoma (P< 0.001). Analyses of receiver operating characteristic curves identified an optimal maximum standardized uptake value cutoff value to predict recurrence of 3.7 for adenocarcinoma, whereas such an indicator could not be identified for squamous cell carcinoma. Although 2-year disease-free survival rates were 70.2% for maximum standardized uptake value ≤6.95 and 59.3% for maximum standardized uptake value >6.95 (P = 0.83) among patients with squamous cell carcinoma, 2-year disease-free survival rates were 93.9% for maximum standardized uptake value ≤3.7 and 52.4% for maximum standardized uptake value >3.7 (P < 0.0001) among those with adenocarcinoma, and notably, 100 and 57.2%, respectively, in patients with Stage I adenocarcinoma (P < 0.0001). On the basis of the multivariate Cox analyses of patients with adenocarcinoma, maximum standardized uptake value (P = 0.008) was a significantly independent factor for disease-free survival as well as nodal metastasis (P = 0.001).

CONCLUSIONS

Maximum standardized uptake value of the primary tumor was a powerful prognostic determinant for patients with adenocarcinoma, but not with squamous cell carcinoma of the lung.

Intratumoral Heterogeneous F-18 Fluorodeoxyglucose Uptake Corresponds with Glucose Transporter-1 and Ki-67 Expression in a Case of Krukenberg Tumor: Localization of Intratumoral Hypermetabolic Focus by Fused PET/MR Image

The expression of glucose transporters (Glut-1, Glut-3), hexokinase-II, and Ki-67 has been proposed to explain intratumoral heterogeneous F-18 fluorodeoxyglucose (FDG) uptake. We report a case of Krukenberg tumor with intratumoral heterogeneous FDG uptake which corresponded well with the expression levels of Glut-1 and ki-67. Fused positron emission tomography (PET)/magnetic resonance (MR) imaging was helpful for localizing the metabolically active area in the tumor specimen. This report elucidates the relationship between the intratumoral heterogeneous FDG uptake and biologic heterogeneity, and shows the usefulness of PET/MR in research on intratumoral heterogeneity.