Paget Disease of Bone Harboring Bone Metastatic Neuroendocrine Cancer: A Case Report.

In this case report, we describe an uncommon case of neuroendocrine cancer of unknown origin began with cauda equina syndrome in a patient affected by Paget disease of bone (PDB). A 76-year-old man with diagnosis of PDB, without history of pain or bone deformity, developed sudden severe low back pain. Bone alkaline phosphatase was increased and MRI and whole-body scintigraphy confirmed the localization of the disease at the third vertebra of the lumbar spine. Treatment with Neridronic Acid was started, but after only 2 weeks of therapy anuria and bowel occlusion occurred together with lower limb weakness and walking impairment. Cauda equina syndrome consequent to spinal stenosis at the level of L2-L3 was diagnosed after admission to Emergency Department and the patient underwent neurosurgery for spinal medulla decompression. The histologic results showed a complete subversion of bone structure in neoplastic tissue, consistent with metastatic neuroendocrine carcinoma of unknown origin. In conclusion, low back pain in the elderly may require deep investigation to individuate rare diseases. In asymptomatic patients with apparently stable PDB, the sudden appearance of pain or neurologic symptoms may alert the clinician for the possibility of other superimposing diseases, like bone metastases.

Effects of oleuropein on tumor cell growth and bone remodelling: Potential clinical implications for the prevention and treatment of malignant bone diseases.

Oleuropein (Ole) is the main bioactive phenolic compound present in olive leaves, fruits and olive oil. This molecule has been shown to exert beneficial effects on several human pathological conditions. In particular, recent preclinical and observational studies have provided evidence that Ole exhibits chemo-preventive effects on different types of human tumors. Studies undertaken to elucidate the specific mechanisms underlying these effects have shown that this molecule may thwart several key steps of malignant progression, including tumor cell proliferation, survival, angiogenesis, invasion and metastasis, by modulating the expression and activity of several growth factors, cytokines, adhesion molecules and enzymes involved in these processes. Interestingly, experimental observations have highlighted the fact that most of these signalling molecules also appear to be actively involved in the homing and growth of disseminating cancer cells in bones and, ultimately, in the development of metastatic bone diseases. These findings, and the experimental and clinical data reporting the preventive activity of Ole on various pathological conditions associated with a bone loss, are indicative of a potential therapeutic role of this molecule in the prevention and treatment of cancer-related bone diseases. This paper provides a current overview regarding the molecular mechanisms and the experimental findings underpinning a possible clinical role of Ole in the prevention and development of cancer-related bone diseases.

The potential of cystatin C as a predictive biomarker in breast cancer.

INTRODUCTION: Breast cancer (BCa) is the leading cause of cancer-related deaths among women. Numerous efforts are being directed toward identifying novel tissue and/or circulating molecular markers that may help clinicians in detecting early-stage BCa patients and in providing an accurate estimation of the prognosis and prediction of response to clinical treatments. In this setting, emerging evidence has indicated Cystatin C (Cyst C), as the most potent endogenous inhibitor of cysteine cathepsins, as a possible useful marker in the clinical management of BCa patients. AREAS COVERED: This review analyzes the results of emerging studies underpinning a potential clinical role of Cyst C, as additional marker in BCa. EXPERT OPINION: Cyst C expression levels have been reported to be altered in tumor tissues and/or in biological fluids of BCa patients. Furthermore, clinical evidence has highlighted a significant correlation between altered Cyst C levels in tumor tissues and/or biological fluids and some clinco-biological parameters of BCa progression. These findings provide evidence for a potential clinical use of Cyst C as a novel marker to improve the clinical and therapeutic management of BCa patients and as a gauge for better clarifying the role of cysteine proteinases in the various steps of BCa progression.

Current status and future directions in the treatment of bone metastases from breast cancer.

The clinical treatment of bone metastasis from breast cancer is currently based on the systemic administration of antiresorptive agents, radiopharmaceuticals, and/or local treatments such as radiation therapy, radiofrequency ablation and surgery. However, these therapeutic options are merely palliative and do not show to have a significant positive impact on patients' survival. In addition, the systemic administration of antiresorptive drugs and/or antitumour agents and/or radiopharmaceuticals may negatively affect normal bone metabolism with detrimental consequences for cancer patients. Hence, the need to identify alternative therapeutic strategies that, based on the hallmarks of bone metastasis, can effectively thwart tumour cell growth while, at the same time, overcoming antitumour drug-induced bone loss and preserving bone health. To this aim, current studies are directed toward the development of new molecules with low toxicity and/or novel drug delivery systems, which may efficiently hinder the growth of metastatic cells, while other studies are focussed on the design of new clinical treatments that, by acting on early stages of breast cancer, may prevent the homing and the subsequent growth of cancer cells in the bone. These treatments might also target occult micro-metastases before their development into clinically evident bone lesions, ultimately hindering bone relapse and disease progression. However, this therapeutic approach implies the identification of early stage breast cancer patients being at high risk of developing bone metastases. The discovery of novel specific biomarkers as predictor of metastatic bone disease may help clinicians in selecting these patients.

On the role of cystatin C in cancer progression.

Cystatin C (Cyst C) is an endogenous inhibitor of lysosomal cysteine proteinases, which has been shown to play a role in several normal and pathological processes. Interestingly, a growing number of experimental and clinical studies suggest that this inhibitor also appears to be implicated in the malignant progression of various human tumors. However, the role of Cyst C in malignant diseases is still controversial as these studies have highlighted that this protein may function either as tumor suppressor or tumor promoter. The specific mechanisms underlying these opposing effects at present remain murky and are the subject of many current investigations. On the other hand, a complete knowledge of these mechanisms is of clinical interest in order to develop new, effective antitumor treatments based on the appropriate use of natural and/or synthetic cysteine proteinase inhibitors. This paper discusses the current findings regarding the role of Cyst C in cancer progression and the clinical implications emerging from these studies.

Clinical Impact of Cystatin C/Cathepsin L and Follistatin/Activin A Systems in Breast Cancer Progression: A Preliminary Report.

This study was directed to assess the clinical impact of the circulating cathepsin L, cystatin C, activin A, and follistatin in breast cancer patients. The serum concentrations of these molecules were determined by immunoenzymatic assays, and their association with some clinico-pathological parameters of breast cancer progression was evaluated. Our results identified cystatin C and activin A as predictive markers for the presence of breast cancer and bone metastasis, respectively. Therefore, these proteins may have a clinical role as circulating biomarkers in the diagnosis and therapeutic monitoring of breast cancer patients.

Vitamin D in cancer chemoprevention.

CONTEXT: There is increasing evidence that Vitamin D (Vit D) and its metabolites, besides their well-known calcium-related functions, may also exert antiproliferative, pro-differentiating, and immune modulatory effects on tumor cells in vitro and may also delay tumor growth in vivo. OBJECTIVE: The aim of this review is to provide fresh insight into the most recent advances on the role of Vit D and its analogues as chemopreventive drugs in cancer therapy. METHODS: A systematic review of experimental and clinical studies on Vit D and cancer was undertaken by using the major electronic health database including ISI Web of Science, Medline, PubMed, Scopus and Google Scholar. RESULTS AND CONCLUSION: Experimental and clinical observations suggest that Vit D and its analogues may be effective in preventing the malignant transformation and/or the progression of various types of human tumors including breast cancer, prostate cancer, colorectal cancer, and some hematological malignances. These findings suggest the possibility of the clinical use of these molecules as novel potential chemopreventive and anticancer agents.

Follistatin as potential therapeutic target in prostate cancer.

Follistatin is a single-chain glycosylated protein whose primary function consists in binding and neutralizing some members of the transforming growth factor-ß superfamily such as activin and bone morphogenic proteins. Emerging evidence indicates that this molecule may also play a role in the malignant progression of several human tumors including prostate cancer. In particular, recent findings suggest that, in this tumor, follistatin may also contribute to the formation of bone metastasis through multiple mechanisms, some of which are not related to its specific activin or bone morphogenic proteins' inhibitory activity. This review provides insight into the most recent advances in understanding the role of follistatin in the prostate cancer progression and discusses the clinical and therapeutic implications related to these findings.

Lenograstim in preventing chemotherapy-induced febrile neutropenia in patients with soft tissue sarcoma.

BACKGROUND: Neutropenia and its complications represent one of the principal dose-limiting toxicity issues in chemotherapeutic regimens for soft tissue sarcoma. Prophylactic granulocyte colony-stimulating factor (G-CSF) reduces the risk of febrile neutropenia (FN). The correct timing of G-CSF administration should be considered in order to optimize the prophylactic treatment. PATIENTS AND METHODS: Patients (≥18 years old) affected by soft tissue sarcoma and treated with epirubicin and ifosfamide, underwent prophylactic treatment with G-CSF (lenograstim at 263 µg) from day 5 to day 9. The proportion of patients experiencing FN and G4 neutropenia was considered. RESULTS: A total of 36 patients receiving three cycles of chemotherapy with epirubicin plus ifosfamide were treated. None developed FN; G4 neutropenia was reported in 17% of patients. No treatment delay or dose reduction was required, no antibiotic therapy was administered and no hospitalization occurred. CONCLUSION: Five-day lenograstim treatment is efficient as prophylaxis of FN for soft tissue sarcoma chemotherapy regimens and allows maintenance of chemotherapy dose intensity.

Serum follistatin in patients with prostate cancer metastatic to the bone.

The clinical significance of circulating follistatin (FLST), an inhibitor of the multifunctional cytokine activin A (Act A), was investigated in patients with prostate cancer (PCa). The serum concentrations of this molecule were determined by an enzyme-linked immunosorbent assay (ELISA) in PCa patients with (M+) or without (M0) bone metastases, in patients with benign prostate hyperplasia (BPH) and in healthy subjects (HS). The effectiveness of FLST in detecting PCa patients with skeletal metastases was determined by the receiver operating characteristic (ROC) curve analysis. Serum FLST was significantly higher in PCa patients than in BPH patients (P = 0.001) or HS (P = 0.011). Conversely, in BPH patients, FLST levels resulted lower than in HS (P = 0.025). In cancer patients the serum concentrations of FLST significantly correlated with the presence of bone metastases (P = 0.0005) or increased PSA levels (P = 0.04). Interestingly, significant differences in the ratio between FLST and Act A serum concentrations (FLST/Act A) were observed between HS and BPH patients (P = 0.001) or PCa patients (P = 0.0005). Finally, ROC curve analysis, highlighted a sound diagnostic performance of FLST in detecting M+ patients (P = 0.0001). However, the diagnostic effectiveness of FLST did not result significantly superior to that of Act A or PSA. These findings suggest that FLST may be regarded as a potential, molecular target in the treatment of metastatic bone disease while its clinical role as soluble marker in the clinical management of PCa patients with bone metastases needs to be better defined.

Activin A and bone metastasis.

Activin A, is a multifunctional cytokine of the transforming growth factor-beta superfamily of growth factors. This molecule has been shown to be implicated in the regulation of a broad range of important biological functions including bone remodelling. Therefore, a deregulation in the activin signalling pathway may result in disturbances of normal bone metabolism and, eventually, in the onset of severe pathological conditions associated with an altered bone resorption. These observations support the concept that Act A might also be implicated in the pathogenesis of bone metastasis. This review provides insight into the most recent advances in understanding the role of this growth factor in the pathogenesis of bone metastasis, and discusses the implications related to the biomedical applications of these findings.

Cathepsin L in metastatic bone disease: therapeutic implications.

Cathepsin L is a lysosomal cysteine proteinase primarily devoted to the metabolic turnover of intracellular proteins. However, accumulating evidence suggests that this endopeptidase might also be implicated in the regulation of other important biological functions, including bone resorption in normal and pathological conditions. These findings support the concept that cathepsin L, in concert with other proteolytic enzymes involved in bone remodeling processes, could contribute to facilitate bone metastasis formation. In support of this hypothesis, recent studies indicate that cathepsin L can foster this process by triggering multiple mechanisms which, in part, differ from those of the major cysteine proteinase of osteoclasts, namely cathepsin K. Therefore, cathepsin L can be regarded as an additional target in the treatment of patients with metastatic bone disease. This review discusses the clinical and therapeutic implications related to these findings.

Serum interleukin-6 in patients with metastatic bone disease: correlation with cystatin C.

The clinical significance of serum interleukin-6 (IL-6) and its correlation with cystatin C (Cyst C), an endogenous inhibitor of cysteine proteinase cathepsin K, was investigated by immunoassays in patients with bone metastasis from breast cancer (BCa) or prostate cancer (PCa). Additional studies were also performed in these patients to assess the effects of zoledronic acid (ZA) administration on the circulating levels of these molecules. Mean IL-6 and Cyst C serum concentrations were significantly increased in BCa patients and in patients with primary osteoporosis (PO) compared to healthy subjects (HS). However, Cyst C, but not IL-6, resulted significantly more elevated in BCa patients than in PO patients. Furthermore, in BCa patients no correlation was highlighted between IL-6 and Cyst C or between these molecules and some clinicobiological parameters of malignant progression. Mean IL-6 levels were also higher in PCa patients and in patients with benign prostatic hyperplasia (BPH) than in HS while Cyst C resulted significantly higher in PCa but not in BPH patients as compared to HS. In PCa patients, a positive correlation was highlighted between IL-6 and number of bone metastases or serum prostate-specific antigen but not with the Gleason score. Conversely, Cyst C levels did not correlate with any of the parameters considered above or with IL-6. Receiver operating characteristic (ROC) curve analysis showed a poor diagnostic accuracy of IL-6 and Cyst C to detect BCa patients with skeletal metastases while, in PCa patients, only IL-6 showed a fair diagnostic performance in this respect. Finally, the administration of ZA to patients with bone metastases induced a statistically significant increase of serum IL-6 and Cyst C only PCa patients with bone metastasis. These data indicate that IL-6 and Cyst C may be regarded as novel targets for cancer treatment and as markers of increased osteoblastic activity associated to bisphosphonate treatments in PCa patients with bone metastases.

Circulating cathepsin K and cystatin C in patients with cancer related bone disease: clinical and therapeutic implications.

The clinical significance of serum cathepsin K and cystatin C was assessed in patients with breast cancer (BCa) or prostate cancer (PCa) with confined disease (M0) or bone metastasis (BM). Cathepsin K and cystatin C circulating levels were determined by ELISAs in 63 cancer patients, in 35 patients with nonmalignant diseases and in 42 healthy blood donors (control group). In BCa patients, cathepsin K serum levels were significantly lower than in sex matched control group (HS; p=0.0008) or in patients with primary osteoporosis (OP; p=0.0009). On the contrary, cystatin C levels were significantly higher in BCa patients than in HS (p=0.0001) or OP (p=0.017). In PCa patients, cathepsin K concentrations did not significantly differ from those measured in sex matched HS or in patients with benign prostatic hyperplasia (BPH). Conversely, cystatin C was more elevated in cancer patients than in controls (p=0.0001) or BPH patients (p=0.0078). Furthermore, in PCa patients, a positive correlation was observed between cystatin C and cathepsin K (r(S)=0.34; p=0.047). No further relationship was highlighted between these molecules and the clinicobiological parameters of BCa or PCa progression including the number of bone lesions. Moreover, ROC curve analysis showed a poor diagnostic performance of cathepsin K and cystatin C in the detection of BM patients. Interestingly, the administration of zoledronic acid (ZA), a bisphosphonate derivative endowed with a potent antiosteoclastic activity, induced in BM patients a marked increase of cathepsin K and cystatin C serum levels compared to baseline values. However, this phenomenon was statistically significant only in the PCa group. In conclusion Cystatin C and cathepsin K may be regarded as possible markers to monitor the therapeutic response to bisphosphonate treatments. Nevertheless, their clinical value as specific gauges of skeletal metastasis remains questionable.

MMP-2, MMP-9 and activin A blood levels in patients with breast cancer or prostate cancer metastatic to the bone.

BACKGROUND: The clinical significance of the circulating levels of activin A and matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) was investigated in patients with breast cancer (BC) or prostate cancer (PC) with (M1) or without (M0) bone metastasis. PATIENTS AND METHODS: MMP-2, MMP-9 and activin A blood concentrations were measured by enzyme immunoassays in 79 cancer patients and in 57 healthy blood donors (HS) who served as a control group. The diagnostic accuracy of these molecules to discriminate between M0 and M1 patients was evaluated by the receiver operating characteristic curve (ROC) and compared to that of tumor markers CA15.3 or prostate-specific antigen (PSA). RESULTS: Activin A and MMP-2 were significantly increased in BC and PC patients as compared to sex-matched HS while MMP-9 levels were more elevated only in the PC patients. Interestingly, in the PC patients, activin A levels were significantly higher than those measured in the BC patients. In this latter group, activin A and CA15.3 but not MMP-2 or MMP-9 were increased in the M1 patients as compared to M0 patients. Furthermore, a significant relationship was also highlighted between activin A concentration and the number of bone metastases and tumor grade, between MMP-9 and tumor grade, and between MMP-2 and CA15.3. ROC curve analysis showed a good diagnostic accuracy for activin A and CA15.3 but a poor accuracy for MMP-2 and MMP-9 in discriminating between M0 and M1 patients. However, CA15.3 retained the best diagnostic accuracy in this respect. In the PC group, only activin A and PSA levels were significantly increased in the M1 patients as compared to the M0 patients. A similar although not statistically significant trend was noted for MMP-9. Interestingly, a significant correlation was observed between PSA and activin A and MMP-9, and between Activin A and Gleason score and the number of skeletal metastases. ROC curve analysis showed a good diagnostic accuracy for activin A, MMP-9 and PSA and a poor diagnostic accuracy for MMP-2 in detecting M1 patients. However, PSA showed the highest diagnostic accuracy. CONCLUSION: Activin A, MMP-2 and MMP-9 may be regarded as possible therapeutic targets in the treatment of metastatic bone disease. However, their usefulness as additional markers of bone metastasis remains to be better defined.

Activin A circulating levels in patients with bone metastasis from breast or prostate cancer.

Recent studies have highlighted that Activin A, a member of the transforming growth factor-beta (TGF-beta) superfamily, may be involved in the regulation of osteoblastic activity and in osteoclast differentiation. Therefore, we have investigated the clinical significance of its circulating levels in patients with bone metastasis. Activin A serum concentrations were determined, by a commercially available enzyme-linked immunosorbent assay kit, in 72 patients with breast cancer (BC) or prostatic cancer (PC) with (BM+) or without (BM-) bone metastases, in 15 female patients with age-related osteoporosis (OP), in 20 patients with benign prostatic hypertrophy (BPH) and in 48 registered healthy blood donors (HS) of both sex (25 female and 23 male). Activin A serum concentrations were significantly increased in BC or PC patients as compared to OP (P < 0.0001) or BPH (P = 0.045), respectively, or to sex matched HS (P < 0.0001). Additionally, these levels resulted more elevated in PC patients as compared to BC patients (P = 0.032). Interestingly, Activin A was significantly higher in BM+ patients than in BM- patients (BC, P = 0.047; PC, P = 0.016). In BC patients, a significant correlation was observed only between Activin A and number of bone metastases (P = 0.0065) while, in PC patients, Activin A levels were strongly correlated with the Gleason score (P = 0.011) or PSA levels (P = 0.0001) and, to a lessen extent, with the number of bone metastases (P = 0.056). Receiver operating characteristic curve (ROC) analysis showed a fair diagnostic accuracy of Activin A to discriminate between BM+ and BM- patients (BC: AUC = 0.71 +/- 0.09, P = 0.03; PC: AUC = 0.73 +/- 0.081, P = 0.005). These findings indicate that Activin A may be implicated in the pathogenesis of bone metastasis. Therefore, this cytokine may be considered a novel potential target for a more selective therapeutic approach in the treatment of skeletal metastasis and may be also useful as additional biochemical marker of metastatic bone disease.

Effects of zoledronic acid on proteinase plasma levels in patients with bone metastases.

BACKGROUND: The effects of the bisphosphonate derivative zoledronic acid (ZA) on the circulating levels of matrix metalloproteinase-2 (MMP-2), matrix metallo-proteinases-9 (MMP-9), cathepsin B (Cath B) and urokinase-type plasminogen activator (uPA) in patients with bone metastasis (BMTS) and the possible correlation with the symptomatic response induced by this drug in these patients were evaluated. PATIENTS AND METHODS: Proteinase levels were determined by enzyme-linked immunosorbent assay (ELISA) in the plasma of 30 patients with painful bone metastases from breast or prostate cancer undergoing multiple treatment with ZA (4 mg i.v., every 4 weeks). Healthy subjects (HS) of both genders (12 female and 30 male) served as the control group. The symptomatic response to ZA was assessed by the visual analog scale score (VAS). RESULTS: The median MMP-2 and MMP-9 pretreatment levels were more elevated in BMTS as compared to HS (p < or = 0.0001). Conversely, uPA levels were lower in BMTS p = 0.0033; no significant difference was observed for Cath B. ZA administration was associated with a symptomatic response (VAS score < or =4) in 25/30patients (83.3%) (p < 0.0001). This phenomenon paralleled a decrease of Cath B and MMP-2 plasma concentrations from baseline values on week 12 (p = 0.05). A similar trend, although not statistically significant, was also noted for MMP-9 and uPA. However, no direct relationship was observed between the analgesic effect induced by ZA and changes in the circulating levels of these enzymes. CONCLUSION: These data show that ZA administration may provide relief from bone pain in patients with diffuse skeletal metastases and confirm a possible implication of cysteine proteinases and matrix metalloproteinases in bone metastasis formation, but not in the pathogenesis of metastatic bone pain.

Cathepsin D expression levels in nongynecological solid tumors: clinical and therapeutic implications.

Cathepsin D is a lysosomal acid proteinase which is involved in the malignant progression of breast cancer and other gynecological tumors. Clinical investigations have shown that in breast cancer patients cathepsin D overexpression was significantly correlated with a shorter free-time disease and overall survival, whereas in patients with ovarian or endometrial cancer this phenomenon was associated with tumor aggressiveness and a degree of chemoresistance to various antitumor drugs such as anthracyclines, cis-platinum and vinca alkaloids. Therefore, a lot of research has been undertaken to evaluate the role and the prognostic value of cathepsin D also in other solid neoplasms. However, conflicting results have been generated from these studies. The discrepancies in these results may, in part, be explained with the different methodological approaches used in order to determine the levels of expression of the enzyme in tumor tissues and body fluids. Further investigations using well-standardized techniques may better define the clinical significance of cathepsin D expression in solid tumors. Nevertheless, evidence emerging from these studied indicates that this proteinase seems to facilitate early phases of tumor progression such as cell proliferation and local dissemination. These findings support the concept that cathepsin D may be a useful marker for identifying patients with highly malignant tumor phenotypes who may need more aggressive clinical treatment; this enzyme may also be considered as a potential target for a novel therapeutic approach in the treatment of solid neoplasms.

Usefulness of alpha-fetoprotein in the diagnosis of hepatocellular carcinoma.

With the widespread use of ultrasonography (US) and computerized tomography (CT), the usefulness of alpha-fetoprotein assay in the diagnosis of hepatocellular carcinoma (HCC) has decreased. The aim of our study was to evaluate the best cut-off value for serum alpha-fetoprotein to discriminate between liver cirrhosis (LC) and HCC and the factors influencing levels in a Sicilian population. Three hundred and seventy-two patients with LC and 197 with HCC-associated LC were studied. The etiology was: HCV in 288 cases (77.4%) of LC and 147 cases (75%) of HCC; HBV in 31 cases (8.3%) of LC and 15 cases (7.6%) of HCC; HCV/HBV in 21 cases (5.6%) of LC and 6 cases (3.0%) of HCC; non-viral in 32 cases (8.6%) of LC and 29 cases (15%) of HCC. Hepatic function was estimated by the Child-Pugh's score; the TNM classification was used in HCC. The area under the ROC curve was 0.81 +/- 0.02; the best discriminant cut-off value, calculated as the value of the maximized likelihood ratio, was 30 ng/ml. At this level sensitivity (SE) was 65%, specificity (SP) 89%, positive predictive value (PPV) 74% and negative predictive value (NPV) 79%. When the patients were divided at this cut-off point into two groups according to viral or non-viral etiology, PPV was 70% versus 94%, respectively (p < 0.05). In the non-viral diseases PPV reached 100% for AFP serum levels of 100 ng/ml, while in the viral diseases PPV was 100% when AFP was greater than 400 ng/ml. There were no significant differences in SE, SP or NPV between viral and non-viral liver diseases. Child's classes B and C were more frequent in HCC (chi 2 of MH 7.7, p < 0.0001). There was a correlation between AFP serum values and TNM classification (p < 0.02) and on multiple logistic regression AFP levels > 30 ng/ml correlated positively only with the TNM stage (p < 0.0001). In conclusion, the best cut-off value for serum AFP in our study population was 30 ng/ml, but at this level sensitivity was low. This cut-off value was more useful in detecting non-viral HCC, because PPV was significantly higher than in viral HCC; therefore, our data confirm that the usefulness of AFP in the diagnosis of HCC of viral etiology is limited, being more useful in HCC of non-viral etiology.