ENETS Consensus Guidelines for the management of patients with digestive neuroendocrine neoplasms: colorectal neuroendocrine neoplasms

PET tracers for somatostatin receptor imaging of neuroendocrine tumors: current status and review of the literature

Neuroendocrine tumors have shown rising incidence mainly due to higher clinical awareness and better diagnostic tools over the last 30 years. Functional imaging of neuroendocrine tumors with PET tracers is an evolving field that is continuously refining the affinity of new tracers in the search for the perfect neuroendocrine tumor imaging tracer. (68)Ga-labeled tracers coupled to synthetic somatostatin analogs with differences in affinity for the five somatostatin receptor subtypes are now widely applied in Europe. Comparison of sensitivity between the most used tracers - (68)Ga-DOTA-Tyr3-octreotide, (68)Ga-DOTA-Tyr3-octreotate and (68)Ga-DOTA-l-Nal3-octreotide - shows little difference and expertise on the specific tracer used, and knowledge regarding physiological uptake might be more important than in vitro-proven differences in affinity. Using isotopes such as (18)F or (64)Cu might improve these PET tracers further.

Neuroendocrine Rectal Tumors: Main Features and Management

The incidence of neuroendocrine tumors of the rectum has been increasing in the last decades, partly due to improved investigation. They are mostly well-differentiated small tumors with a rather good overall prognosis. In the last few years, some aspects of neuroendocrine tumors have been evolving. In 2010, the World Health Organization proposed a new classification, indicating that these tumors, as a category, should be considered malignant. Afterwards the European Neuroendocrine Tumor Society published their guidelines for the management of colorectal neoplasms. Treatment algorithm is mainly based on tumor size and grading and, in general, well-differentiated rectal tumors <2 cm can be endoscopically resected. Endorectal ultrasound plays a particularly important role by accurately assessing tumor size and depth of invasion prior to resection. There are no specific recommendations on the optimal endoscopic resection method, but data from recent studies suggests that modified endoscopic mucosal resection techniques and endoscopic submucosal dissection have superior complete resection rates.

Well-differentiated neuroendocrine neoplasia: relapse-free survival and predictors of recurrence after curative intended resections

BACKGROUND

Resection with curative intention is the cornerstone of treatment in patients with neuroendocrine tumors. A proportion of patients will relapse after R0 resection, but the factors predictive of recurrence are not well understood.

METHODS

A database established 1998 at the University Hospital Marburg was queried for all patients with documented R0 resection. Recurrence-free survival and overall survival were estimated using the Kaplan-Meier method. Uni- and multivariate analyses were performed.

RESULTS

180 patients with a median age of 52 years entered the analysis. We observed 77 recurrences after a median time of 2.9 years. 24% of the recurrences occurred later than 5 years after operation. Median recurrence-free survival of the whole cohort was 101 months. In univariate analysis grade by Ki-67, stage, high lymph node ratio and microangioinvasion were significant predictors of recurrence. On multivariate analysis these parameters were confirmed as independent prognostic parameters with stage and microangioinvasion being the most important predictors.

CONCLUSIONS

After R0 resection of neuroendocrine tumors, postoperative surveillance should be extended to at least 10 years. Patients with distant metastases and microangioinvasion are at high risk of recurrence. Clinical trials of adjuvant treatment protocols are indicated in these patients.

Neuroendocrine Carcinomas of the Gastroenteropancreatic System: A Comprehensive Review

To date, empirical literature has generally been considered lacking in relation to neuroendocrine carcinomas (NECs), the highly malignant subgroup of neuroendocrine neoplasms. NECs are often found in the lungs or the gastroenteropancreatic (GEP) system and can be of small or large cell type. Concentrating on GEP-NECs, we can conclude that survival times are poor, with a median of only 4–16 months depending on disease stage and primary site. Further, this aggressive disease appears to be on the rise, with incidence numbers increasing while survival times are stagnant. Treatment strategies concerning surgery are often undecided and second-line chemotherapy is not yet established. After an analysis of over 2600 articles, we can conclude that there is indeed more empirical literature concerning GEP-NECs available than previously assumed. This unique review is based on 333 selected articles and contains detailed information concerning all aspects of GEP-NECs. Namely, the classification, histology, genetic abnormalities, epidemiology, origin, biochemistry, imaging, treatment and survival of GEP-NECs are described. Also, organ-specific summaries with more detail in relation to disease presentation, diagnosis, treatment and survival are presented. Finally, key points are discussed with directions for future research priorities.

Endoscopic mucosal resection of early stage colon neuroendocrine carcinoma

Early stage colorectal neuroendocrine carcinoma is rare. A small colon tumour was found in a 56-year-old man during diagnostic colonoscopy performed after a positive faecal occult blood test, and he was referred for treatment. A slightly reddish superficial elevated lesion with a shallow depression 10 mm in size was found in the transverse colon. Magnifying narrow-band imaging revealed disrupted irregular microvessels and the absence of a surface pattern in the depressed area. En bloc endoscopic mucosal resection (EMR) of the tumour was undertaken. The tumour was positive for chromogranin A and synaptophysin, and had a mitotic rate of >20/10 high-power fields and a Ki-67 proliferative index of >50%; it was diagnosed as a neuroendocrine carcinoma. The tumour minimally invaded the submucosa (300 μm) without lymphovascular involvement. The patient was followed up carefully, and at 1 year after EMR, no recurrence was found using colonoscopy and CT scans.

Prognostic Significance of Defining L-Cell Type on the Biologic Behavior of Rectal Neuroendocrine Tumors in Relation with Pathological Parameters

Purpose

In 2010, the World Health Organization categorized L-cell type neuroendocrine tumors (NETs) as tumors of uncertain malignancy, while all others were classified as malignant. However, the diagnostic necessity of L-cell immunophenotyping is unclear, as are tumor stage and grade that may guide diagnosis and management. To clarify the predictive markers of rectal neuroendocrine neoplasms (NENs), 5- and 10-year overall survival (OS) was analyzed by pathological parameters including L-cell phenotype.

Materials and Methods

A total of 2,385 rectal NENs were analyzed from our previous multicenter study and a subset of 170 rectal NENs was immunophenotyped.

Results

In univariate survival analysis, tumor grade (p < 0.0001), extent (p < 0.0001), size (p < 0.0001), lymph node metastasis (p=0.0063), and L-cell phenotype (p < 0.0001) showed significant correlation with the prognosis of rectal NENs; however, none of these markers achieved independent significance in multivariate analysis. The 10-year OS of tumors of NET grade 1, < 10 mm, the mucosa/submucosa was 97.58%, 99.47%, and 99.03%, respectively. L-Cell marker, glucagon II (GLP-1&2), with a cut off score of > 10, is useful in defining L-Cell type. In this study, an L-cell immunophenotype was found in 83.5% of all rectal NENs and most, but not all L-cell type tumors were NET G1, small (< 10 mm) and confined to the mucosa/submucosa.

Conclusion

From these results, the biological behavior of rectal NENs does not appear to be determined by L-cell type alone but instead by a combination of pathological parameters.

Efficacy and safety of endoscopic resection therapies for rectal carcinoid tumors: a meta-analysis

PURPOSE

Several endoscopic resection therapies have been applied for the treatment of rectal carcinoid tumors. However, there is currently no consensus regarding the optimal strategy. We performed a meta-analysis to compare the efficacy and safety of endoscopic mucosal resection (EMR) or modified EMR (m-EMR) versus endoscopic submucosal dissection (ESD) for the treatment of rectal carcinoid tumors.

MATERIALS AND METHODS

PubMed, Web of Science, Medline, Embase and CNKI were searched up to the end of January 2014 in order to identify all studies on the effects of EMR (or m-EMR) and ESD on rectal carcinoid tumors.

RESULTS

A total of fourteen studies involving 782 patients were included. The pooled data suggested a significantly higher rate of pathological complete resection among patients treated with ESD or m-EMR than those treated with EMR [odds ratio (OR)=0.42, 95% confidence interval (CI): 0.25-0.71; OR=0.10, 95% CI: 0.03-0.33, respectively], while there was no significant difference between the m-EMR group and ESD group (OR=1.19, 95% CI: 0.49-2.86); The procedure time of ESD was longer than EMR or m-EMR groups [mean differences (MD)=-11.29, 95% CI: -14.19 - -8.38, MD= -10.90, 95% CI: -18.69 - -3.11, respectively], but it was insignificance between the EMR and m-EMR groups. No significant differences were detected among the treatment groups with regard to complications or recurrence.

CONCLUSION

The results of this meta-analysis suggest that treatment of rectal carcinoid tumors with ESD or m-EMR is superior to EMR, and the efficacy of m-EMR is equivalence to ESD treatment. However, more well-designed studies are needed to confirm these findings.

GEP-NETS update: a review on surgery of gastro-entero-pancreatic neuroendocrine tumors

The incidence of neuroendocrine tumors (NETs) has increased in the last decades. Surgical treatment encompasses a panel of approaches ranging from conservative procedures to extended surgical resection. Tumor size and localization usually represent the main drivers in the choice of the most appropriate surgical resection. In the presence of small (<2 cm) and asymptomatic nonfunctioning NETs, a conservative treatment is usually recommended. For localized NETs measuring above 2 cm, surgical resection represents the cornerstone in the management of these tumors. As they are relatively biologically indolent, an extended resection is often justified also in the presence of advanced NETs. Surgical options for NET liver metastases range from limited resection up to liver transplantation. Surgical choices for metastatic NETs need to consider the extent of disease, the grade of tumor, and the presence of extra-abdominal disease. Any surgical procedures should always be balanced with the benefit of survival or relieving symptoms and patients' comorbidities.

Paraneoplastic brainstem encephalitis in a patient with exceptionally long course of a metastasized neuroendocrine rectum neoplasm

Background

Paraneoplastic neurological syndromes (PNS) have frequently been described in patients with lung or breast cancer. However, some reports also described a correlation to carcinoid tumors, probably triggered via the excessive release of hormones.

Case presentation

We report the case of a 40-year-old woman that was diagnosed with a neuroendocrine neoplasm (NEN) of the rectum and multiple synchronous liver metastases ten years ago. She initially responded well to transarterial chemoembolization (TACE), resulting in prolonged disease stabilization. However, ten years after initial diagnosis the patient developed unspecific neurological symptoms that could not be classified by standard neurological diagnostic work-up. Special laboratory analysis revealed a high titer of anti-Ri (ANNA-2), a well-characterized antibody that is associated with paraneoplastic neurologic syndromes. The patient’s symptoms improved markedly after a 5-day-course of high-dose glucocorticoid therapy. To our knowledge, this is the first report of a Ri-positive PNS in a patient with hormone-negative rectal NEN.

Conclusion

PNS can complicate the patient’s clinical course, response to treatment, impact prognosis and even be interpreted as metastatic spread. However, owing to their rarity, the knowledge of these syndromes is very helpful in order to be able to provide evidence-based diagnostic and therapeutic approaches.

Endoscopically identified well-differentiated rectal carcinoid tumors: impact of tumor size on the natural history and outcomes

BACKGROUND

There is a paucity of data pertaining to the natural history and outcomes of patients with well-differentiated rectal carcinoids.

OBJECTIVE

To correlate endoscopic size with the natural history and outcome.

DESIGN

Retrospective study.

SETTING

Single tertiary referral center.

PATIENTS

Eighty-seven patients with endoscopically identified well-differentiated rectal carcinoid tumors.

INTERVENTION

Colonoscopy.

MAIN OUTCOME MEASUREMENTS

Prevalence of metastasis at diagnosis, disease progression, and survival.

RESULTS

Metastasis was present at diagnosis in 3%, 66%, and 73% of tumors measuring ≤10 mm, 11 to 19 mm, and ≥20 mm, respectively. Metastasis was predicted with 100% sensitivity and 87% specificity using an endoscopic lesion size ≥9 mm. In patients without identified metastasis, 64% were identified during screening colonoscopy. Within this select cohort, subsequent metastasis was discovered only at distant extra pelvic sites, in 1.6%, 50%, and 100% of patients with tumors initially measuring ≤10 mm, 11 to 19 mm, and ≥20 mm, respectively. The carcinoid related 5- and 10-year survival rates for locally confined disease were 96%. The corresponding survival rates for local and advanced metastatic disease were 60% and 35%, respectively.

LIMITATIONS

Subjective estimation of tumor size, mitotic index or Ki-67 labeling index not reported, and lack of formal and standardized baseline staging algorithm and surveillance program.

CONCLUSIONS

The clinical behavior of 11- to 19-mm tumors appears to mimic that of larger (>20 mm) lesions with respect to the presence of metastasis at diagnosis and disease progression. Therefore, if local therapy is contemplated, we propose to make a distinction between ≤10-mm and 11- to 19-mm tumors, favoring an aggressive staging and management protocol for 11- to 19-mm carcinoid tumors.

Surveillance strategy for rectal neuroendocrine tumors according to recurrence risk stratification

BACKGROUND/AIM

Rectal neuroendocrine tumors (NETs) have been increasing in incidence. However, the recommendations for disease surveillance after tumor resection have not been well established. We evaluated the long-term outcomes of rectal NETs and surveillance strategies according to recurrence risk stratification.

METHODS

From January 2000 to July 2011, 188 patients diagnosed with rectal NETs were included in this study. Patient characteristics, treatment methods, recurrence rates, risk factors of recurrence, and surveillance schedules were analyzed.

RESULTS

The male-to-female ratio was 1.29:1 and the mean age at diagnosis was 50.6 years. The mean tumor size was 6.5 (range 1-30) mm. A total of 144 patients (76.6 %) were treated with endoscopic resection, and 44 patients (23.4 %) were treated with surgical resection as the initial treatment. During the follow-up period, ten patients (5.3 %) had disease recurrence, including one case of local recurrence and nine cases of recurrence at a distant site. Tumor size of >10 mm, invasion of the muscularis propria, increased mitotic index, lymphovascular invasion, and regional lymph node metastases were statistically significant predictors of recurrence by univariate analysis. Among the 152 patients without risk factors of recurrence, only one patient who underwent transanal resection had a local recurrence at 15 months after surgery.

CONCLUSION

Our patients with rectal NETs showed favorable clinical outcomes and had a low rate of recurrence. Intensive surveillance with endoscopy or imaging study may not be required in patients without risk factors for recurrence.

Rare tumors of the rectum. Narrative review

Most rectal neoplasms are adenocarcinomas, but there is a small percentage of tumors which are of other histological cell lines such as neuroendocrine tumors, sarcomas, lymphomas and squamous cell carcinomas, which have special characteristics and different treatments. We have reviewed these rare tumors of the rectum from a clinical and surgical point of view.

The clinical presentation and management of carcinoid heart disease

Carcinoid heart disease is a major cause of morbidity and mortality in patients with metastatic neuroendocrine tumours (NETs). Although cases of carcinoid syndrome and severe carcinoid heart disease requiring urgent intervention are well described, many patients with significant carcinoid heart disease may have insidious symptoms or even be asymptomatic. As haemodynamically significant carcinoid heart disease may be clinically silent, specific and individualised considerations must be made as to the most appropriate clinical criteria and time point at which surgical valve replacement should be undertaken in patients with carcinoid heart disease.

Endoscopic resection therapies for rectal neuroendocrine tumors: a systematic review and meta-analysis

BACKGROUND AND AIM

Among various endoscopic resection therapies, including conventional endoscopic mucosal resection (EMR) only with a snare after submucosal injection, modified EMR (m-EMR) with other assistant devices such as a ligation band or a suction cap, and endoscopic submucosal dissection (ESD), we aimed to study which is the best choice for rectal neuroendocrine tumors.

METHODS

A broad literature research was performed, and a systematic review and meta-analysis were conducted.

RESULTS

Ten retrospective studies with 650 patients were included. Complete resection rates were significantly higher in the ESD group compared with the EMR group (relative risk [RR] 0.89, 95% confidence interval [CI] [0.79, 0.99]), in the m-EMR group compared with the conventional EMR group (RR 0.72, 95% CI [0.60, 0.86]), and was comparable between the ESD group and the m-EMR group (RR 1.03, 95% CI [0.95, 1.11]). Procedure time was significantly longer in the ESD group than in the EMR group (standard mean differences -1.37, 95% CI [-1.99, -0.75]), but there was no significant difference between that of the m-EMR group and ESD group (standard mean differences -1.50, 95% CI [-3.14, 0.14]). Local recurrence occurred in five cases in the EMR group (5/328) and did not occur in the ESD group (0/209).

CONCLUSIONS

ESD or m-EMR techniques could be applied to rectal neuroendocrine tumors with indications for endoscopic treatment. m-EMR procedures appear to be comparable with ESD in the treatment of rectal neuroendocrine tumors. However, the findings have to be carefully interpreted due to the lower level of evidence.

New insights into the role of chronic inflammation and cytokines in the etiopathogenesis of gastroenteropancreatic neuroendocrine tumors

Although previously considered rare, recent epidemiological studies have revealed that the incidence (3.6/100,000) and prevalence (35/100,000) of gastroenteropancreatic neuroendocrine tumors (GEP-NETs) has increased over the past few decades. Despite the progress in the understanding of GEP-NET molecular biology, there is still little advance in the early diagnosis due to lack of specific tumor markers. As the tumors are mostly detected in their late stage, they are not well controlled by either biotherapy or conventional chemotherapy, and thus represent a significant clinical issue. Chronic inflammation has been implicated in the development of GEP-NETs. This review presents recent findings that link pro-inflammatory cytokines to the molecular basis of GEP-NET tumorigenesis, leading to a more personalized approach to disease management and therapy.

Diagnostic and therapeutic role of endoscopy in gastroenteropancreatic neuroendocrine neoplasms

Gastroenteropancreatic neuroendocrine neoplasms have substantially increased over the last decades. Because of the indolent clinical course of the disease even in advance stages and the rise in the incidental diagnosis of small asymptomatic lesions, the prevalence of gastroenteropancreatic neuroendocrine neoplasms is higher than that of pancreatic, gastric and oesophageal adenocarcinomas, making them the second most prevalent cancer type of the gastrointestinal tract. This increase in the overall prevalence of gastroenteropancreatic neuroendocrine neoplasms has been paralleled by a growth in the importance of the endoscopist in the care of these patients, who usually require a multidisciplinary approach. In this manuscript the diagnostic and therapeutic role of endoscopic for gastroenteropancreatic neuroendocrine neoplasms will be reviewed.

Prognostic impact of diagnosing colorectal neuroendocrine carcinoma using the World Health Organization 2010 classification

BACKGROUND

Neuroendocrine carcinomas (NECs) arising in the large intestine are rare neoplasms with highly aggressive behavior. The aim of the study was to compare the 2000 and 2010 World Health Organization (WHO) classification of these colorectal NECs.

METHODS

We conducted a retrospective study of patients diagnosed with colorectal NECs according to the WHO 2000 classification who underwent surgery at the Asan Medical Center between May 2000 and December 2010. The data were reevaluated to assess their consistency with the WHO 2010 classification.

RESULTS

For 20 of the 34 patients (59%), the 2000 and 2010 WHO classifications yielded the same NEC diagnosis (NEC group), whereas for 14 of the 34 patients (41%), the WHO 2010 classification mandated a diagnosis of G1 or G2 neuroendocrine tumors (NETs) rather than NECs (G1/G2 NET group). The NEC group was older than the G1/G2 NET group (64 vs 55 years; P = .05). Tumor differentiation in the NEC group was poorer than in the G1/G2 NET group (percentage of poorly differentiated tumor, 70% vs 7%; P < .001). In both groups based on the 7th American Joint Committee on Cancer staging, most of the tumors were advanced at the time of diagnosis, reaching stage IIIB (6 NEC vs 10 NET) and stage IV (10 NEC vs 3 NET). The 5-year overall survival in the 2 groups was different (P = .02), but not the 5-year disease-free survival (P = .24).

CONCLUSION

These results indicate that the WHO 2010 classification of colorectal NEC is more accurate and has better prognostic value than the WHO 2000 classification.

Factors associated with lymph node metastasis in radically resected rectal carcinoids: a systematic review and meta-analysis

BACKGROUND

Although various guidelines regarding neuroendocrine tumors were released, treatment for rectal neuroendocrine tumors with size between 1 and 2 cm has not been explicitly elucidated. The determinant factor of the choice between endoscopic resection and radical surgery is whether lymph node involvement exists.

AIM

This study aims to explore factors associated with lymph node involvement in rectal neuroendocrine tumors by conducting a meta-analysis.

METHODS

A broad literature research of Pubmed, Embase&Medline, and The Cochrane Library was performed, and systematic review and meta-analysis about factors associated with lymph node involvement were conducted.

RESULTS

Seven studies were included in this meta-analysis. Tumor size > 1 cm (odds ratio (OR) 6.72, 95% confidence interval (CI) [3.23, 14.02]), depth of invasion (OR 5.06, 95% CI [2.30, 11.10]), venous invasion (OR 5.92, 95% CI [2.21, 15.87]), and central depression (OR 3.00, 95% CI [1.07, 8.43]) were significantly associated with lymph node involvement.

CONCLUSION

The available clinical evidence suggests that tumor size > 1 cm, invasion of muscularis properia, venous invasion, and central depression could be risk factors of lymph node involvement, while other factors reported by few studies need further research.

Surgical treatment of neuroendocrine tumors (including carcinoid)

PURPOSE OF REVIEW

Neuroendocrine tumors of the gastrointestinal tract are rare tumors, but as they have become recognized more often, and their care has been concentrated at some centers, standards of care have developed. With these standards, questions in the field have led to focused studies to inform practitioners.

RECENT FINDINGS

The efficacy and morbidity of care have been well delineated now for pancreatic neuroendocrine tumors, as well as the effect of stretching the bounds of resection to include vascular reconstruction. The management of the gallbladder in patients with mid-gut carcinoid tumors and palliative approaches to mesenteric vein compression have been reported. The operative management of liver metastases shows the benefit of this approach, even when incomplete, as well as the safety of performing complex procedures in appropriate situations.

SUMMARY

Some of the difficult or controversial decision areas in the surgical care of patients with neuroendocrine tumors are now more clear because of recently reported data.

Clinical and prognostic features of rectal neuroendocrine tumors

BACKGROUND

Rectal neuroendocrine tumors (NETs) are among the most common NETs. The aim was to validate European Neuroendocrine Tumor Society (ENETS)/North American Neuroendocrine Tumor Society (NANETS) staging and grading systems with regard to clinical outcomes.

METHODS

A comprehensive database was constructed from existing databases of the Mount Sinai Division of Gastrointestinal Pathology and the Carcinoid Cancer Foundation. Analysis was performed on 141 patients identified with rectal NETs seen at Mount Sinai Hospital between 1972 and 2011.

RESULTS

The median age was 52.7 years; 43% were males. Average tumor size was 0.88 cm. NETs <1 cm accounted for 75.6% of the tumors. Stage I, II, III and IV accounted for 79.4, 2.8, 5.0 and 12.8% of the tumors, respectively. G1 tumors accounted for 88.1%, G2 8.3% and G3 3.6%. Of G1 tumors, 94.6% were stage I and 5.4% were stage IV. The median survival time for all 141 patients was 6.8 years (range, 0.8-34.7 years). The overall 5-year survival rate was 84.4%. The 5-year survival rates for patients in stages I-IV were 92.7, 75.0, 42.9 and 33.2%, respectively. The 5-year survival rates for patients with G1-G3 tumors were 87.7, 47.6 and 33.3%, respectively. Univariate analysis of increased survival showed significance for lower stage, lower grade, smaller size, absence of symptoms and endoscopically treated tumors. Multivariate analysis showed that stage alone was statistically significant as the strongest predictor of survival.

CONCLUSION

The results of our study validated ENETS/NANETS guidelines for staging and grading of rectal NETs in the US setting of a tertiary referral center. Staging according to ENETS/NANETS guidelines should be used in the treatment algorithm rather than size alone.

Colonic and rectal NET's

Neuroendocrine tumours of the Colon and Rectum are rare but are increasing in incidence as a result of greater investigation with endoscopy and improved histological reporting. Classification with the 2010 WHO TNM staging system as well as grading based on the Ki-67 index has led to improved prognostic assessment. The use of Endoanal Ultrasound has increased the sensitivity of detection of depth of invasion and lymphovascular involvement, which is associated with a poor prognosis. Standard polypectomy has largely been replaced by endoscopic mucosal resection of smaller polyps, although newer techniques such as band ligation or endoscopic submucosal dissection are likely to be associated with less residual disease. The management of advanced disease remains a challenge but new treatments such as Peptide Receptor Targeted therapy and molecular targeted treatments offer hope of improved progression free survival in non-resectable disease.

Surgery for GEP-NETs

Surgery is the only treatment that may cure the patient with gastroentero-pancreatic (GEP) neuroendocrine tumours (NET) and neuroendocrine carcinomas (NEC) and should always be considered as first line treatment if R0/R1 resection can be achieved. The surgical and interventional procedures for GEP-NET are accordingly described below. Life-long follow-up should be performed in almost all patients at a specialized NET center.

Impact of Ga-68 DOTATOC PET/CT on the diagnosis and treatment of patients with multiple endocrine neoplasia

PURPOSE

To evaluate the impact of Ga-68 DOTATOC PET/CT on diagnosis and therapeutic management of patients with multiple endocrine neoplasia (MEN).

MATERIALS AND METHODS

We did 28 Ga-68 DOTATOC PET/CT in 21 MEN patients (10 female, 11 men; mean age 41.3 years). 109 lesions detected were classified into MEN-associated lesions [i.e., neuroendocrine tumors (NET)] and non-MEN-associated lesions for PET, CT, and PET/CT. The impact of Ga-68 DOTATOC PET/CT on diagnosis and therapeutic management of patients with MEN were assessed by the records of the interdisciplinary NET tumor board including histopathological findings, clinical and radiological follow-up.

RESULTS

Ga-68 DOTATOC PET/CT had an impact on diagnosis and therapeutic management in 10/21 (47.6%) MEN patients. For detecting NET lesions in MEN patients Ga-68 DOTATOC PET/CT reached a sensitivity/specificity of 91.7%/93.5%. There was a significant difference for the detection rate between Ga-68 DOTATOC PET/CT and CT alone (p < 0.001) both using contrast-agent (p = 0.002) or not (p < 0.001) and also a significant difference between contrast-enhanced (CE-) CT and non-CE-CT alone (p = 0.006).

CONCLUSIONS

GA-68 DOTATOC PET/CT allows a high detection rate of NET lesions in the context of MEN-1 syndrome as well as influence therapeutic management in nearly up to half of the patients. GA-68 DOTATOC PET/CT should include a CE-CT to improve MEN-associated NET lesion detection.