Impact of grade on workup of rectal neuroendocrine tumors: a retrospective cohort study : Grade impact on workup of rectal NETs

BACKGROUND

Rectal neuroendocrine tumors (RNETs) are often discovered on screening colonoscopy. Indications for staging and definitive resection are inconsistent in current guidelines. We evaluated the role of grade in guiding staging and procedural decision-making.

METHODS

Patients with biopsy confirmed RNETs between 2004 and 2015 were reviewed. Baseline characteristics, staging investigations (biochemical and imaging), and endoscopic/surgical treatment were recorded. Associations between grade, preoperative staging, interventions, and survival were determined using Fisher-Freeman-Halton Exact, log-rank, and Kaplan-Meier analysis.

RESULTS

Amongst 139 patients with RNETs, 9% were aged ≥ 75 years and 44% female. Tumor grade was: 73% grade 1 (G1), 18%, grade 2 (G2) and 9% grade 3 (G3). Staging investigations were performed in 52% of patients. All serum chromogranin A and 97% of 24-hour urine 5-hydroxyindoleacetic acid tests were normal. The large majority of staging computed tomography (CT) scans were negative (76%) with subgroup analysis showing no G1 patients with CT identified distant disease compared with 38% of G2 and 50% of G3 patients (p < 0.001). G1 patients were more likely to achieve R0/R1 resections compared to G2 (95% vs. 50%, p < 0.001) and G1 patients had significantly better 5-year overall survival (G1: 98%, G2: 67%, G3: 10%, p < 0.001).

CONCLUSION

Tumor grade is important in preoperative workup and surgical decision-making. Biochemical staging may be omitted but staging CT should be considered for patients with grade ≥ 2 lesions. Anatomic resections should be considered for patients with grade 2 disease.

Symptom Burden and Time from Symptom Onset to Cancer Diagnosis in Patients with Early-Onset Colorectal Cancer: A Multicenter Retrospective Analysis

Background: The incidence of colorectal cancer (CRC) is decreasing in individuals >50 years due to organised screening but has increased for younger individuals. We characterized symptoms and their timing before diagnosis in young individuals. Methods: We identified all patients diagnosed with CRC between 1990-2017 in British Columbia, Canada. Individuals <50 years (n = 2544, EoCRC) and a matched cohort >50 (n = 2570, LoCRC) underwent chart review to identify CRC related symptoms at diagnosis and determine time from symptom onset to diagnosis. Results: Across all stages of CRC, EoCRC presented with significantly more symptoms than LoCRC (Stage 1 mean ± SD: 1.3 ± 0.9 vs. 0.7 ± 0.9, p = 0.0008; Stage 4: 3.3 ± 1.5 vs. 2.3 ± 1.7, p < 0.0001). Greater symptom burden at diagnosis was associated with worse survival in both EoCRC (p < 0.0001) and LoCRC (p < 0.0001). When controlling for cancer stage, both age (HR 0.87, 95% CI 0.8-1.0, p = 0.008) and increasing symptom number were independently associated with worse survival in multivariate models. Conclusions: Patients with EoCRC present with a greater number of symptoms of longer duration than LoCRC; however, time from patient reported symptom onset was not associated with worse outcomes.

Clinical impact of unsuccessful subcutaneous administration of octreotide LAR instead of intramuscular administration in patients with metastatic gastroenteropancreatic neuroendocrine tumors

Octreotide LAR is a long-acting somatostatin analogue (SSA) used in the management of metastatic gastroenteropancreatic neuroendocrine tumors (GEP NETs). It requires intramuscular (IM) injection. Missed IM injections cause subcutaneous nodules (SCNs) on radiologic images. We reviewed the rates of SCNs in a real-world cohort of GEP NETs receiving octreotide LAR and explored treatment outcomes. Patients commencing octreotide LAR between August 5, 2010 and March 8, 2018 at a single cancer center in Canada were identified from pharmacy records. Patients were included if they had a computed tomography (CT) scan performed at the time of progression and a preceding CT with pelvis included to enable assessment for the presence of nodules. Fisher's exact test was used to examine predictors of SCNs, and Kaplan-Meier curves summarized differences in progression free (PFS) and overall survival (OS) that were compared with log-rank tests. Of 243 patients receiving octreotide LAR, 45 had all required CT images available for central review. SCNs were found in 20/45 (44%) of patients on the last scan showing stable disease before progression and were numerically but not statistically more likely in females (OR: 2.36, 95% CI: 0.66-8.29, p = .23). There was an increased risk of SCNs in patients with a skin-to-muscle distance >38 mm (the length of an octreotide LAR needle) on CT (OR: 5.09, 95% CI: 1.39-16.6, p = .018) and a trend toward increased risk in obese patients (OR: 5.71, 95% CI: 1.26-23.4, p = .061). PFS (HR: 1.01, 95% CI: 0.56-1.78, p = .98) and OS (HR: 0.86, 95% CI: 0.41-1.8, p = .70) was similar between those with/without SCNs. In conclusion, almost half of patients receiving octreotide LAR had SCNs; however, missed administration of SSA did not appear to result in worse survival in this small study. Factors such as sex, younger age skin-to-muscle distance, and obesity may affect SCN development and should be considered when choosing an SSA.

Treatment Patterns and Outcomes of Pre-operative Neoadjuvant Radiotherapy in Patients with Early-onset Rectal Cancer

Pre-operative radiotherapy for early-stage rectal cancer has risks and benefits that may impact treatment choice in young patients. We reviewed radiotherapy use and outcomes for rectal cancer by age. Patients with early-stage rectal cancer in the Canadian province of British Columbia from 2002-2016 were identified (n=6232). Baseline characteristics, treatment response, overall survival (OS), disease-free survival (DFS), disease-specific survival (DSS), and locoregional recurrence rate (LRR) were compared between patients &lt;50 (early-onset) (n=532) and ≥50 years old (average-onset) (n=5700). Early-onset patients were more likely to receive pre-operative chemoradiotherapy than short-course radiotherapy (OR: 2.20, 95% CI: 1.67-2.89, P&lt;0.0001), but also had higher nodal (P=0.00096) and overall clinical staging (P=0.033). Cancer downstaging and pCR rates were similar in those receiving neoadjuvant chemoradiotherapy by age. Early-onset and average-onset patients had similar DSS (P=0.91) and DFS (P=0.27) in multivariate analysis unless non-colorectal deaths, which were higher in older patients, were censored in the DFS model (HR: 1.30, 95% CI: 1.01-1.68, P=0.042). LRR also did not differ between age groups (P=0.88). Outcomes did not differ based on radiotherapy type. Young patients with rectal cancer are more likely to present with higher staging and receive long-course chemoradiotherapy. DSS did not differ by age group, however young patients had worse DFS when we censored competing risks of death in older patients.

Association between surveillance imaging and survival outcomes in small bowel neuroendocrine tumors

BACKGROUND

Surveillance guidelines following the resection of small bowel neuroendocrine tumors (SB-NETs) are inconsistent. We evaluated the impact of surveillance imaging on SB-NET recurrence and overall survival (OS).

METHODS

Patients with completely resected SB-NETs referred to a provincial cancer center (2004-2015) were reviewed. Associations between imaging frequency, recurrence, post-recurrence treatment, and OS were determined using univariate and Cox-regression analyses.

RESULTS

Among 195 completely resected SB-NET patients, 31% were ≥70 years, 43% were female, and 80% had grade 1 disease. Imaging frequency was predictive of recurrence (hazard ratio 2.52, 95% confidence interval 1.84-3.46, p < 0.001). 72% underwent interventions for recurrent disease. Patients who were treated for the recurrent disease had comparable OS to those who did not recur (median 152 vs. 164 months; p = 0.25). Imaging frequency was not associated with OS in those with treated recurrent disease (p = 0.65). Patients who recurred underwent more computerized tomography (CT) scans than those who did not recur (CT: 1.47 ± 0.89 vs. 1.02 ± 0.81 scans/year, p < 0.001). Detection of disease recurrence was 5%-7% per year during the first 6 years of surveillance and peaked at 17% in Year 9.

CONCLUSION

Less frequent imaging over a longer duration should be emphasized to capture clinically relevant recurrences that can be treated to improve OS.

Multisite gynecologic endometrioid adenocarcinomas: Can mutation profiling be used to distinguish synchronous primary cancers from metastases?

It is well recognized that some patients with endometrioid gynecological cancers have tumors arising in multiple sites (ovary, endometrium, and endometriosis) at the time of diagnosis. Molecular analysis has helped discern whether these multisite cancers represent synchronous primary tumors or alternatively metastatic disease. We present a complex case of a patient with endometrioid carcinomas arising in multiple sites. We discuss the use of mutation profiling to discern clonality and highlight how this information may inform the clinical management of such cases.

Characterizing the KRAS G12C mutation in metastatic colorectal cancer: a population-based cohort and assessment of expression differences in The Cancer Genome Atlas

Introduction

In metastatic colorectal cancer (mCRC), RAS mutations impart inferior survival and resistance to anti-epidermal growth factor receptor (EGFR) antibodies. KRAS G12C inhibitors have been developed and we evaluated how KRAS G12C differs from other RAS mutations.

Patients and Methods

This retrospective review evaluated patients in British Columbia, Canada with mCRC and RAS testing performed between 1 January 2016 and 31 December 2018. Sequencing information from The Cancer Genome Analysis (TCGA) was also obtained and analysed.

Results

Age at diagnosis, sex, anatomic location and stage at diagnosis did not differ by RAS mutation type. Progression free survival on first chemotherapy for patients with metastatic KRAS G12C tumours was 11 months. Median overall survival did not differ by RAS mutation type but was worse for both KRAS G12C (27 months) and non-G12C alterations (29 months) than wildtype (43 months) (p = 0.01). Within the TCGA, there was no differential gene expression between KRAS G12C and other RAS mutations. However, eight genes with copy number differences between the G12C and non-G12C RAS mutant groups were identified after adjusting for multiple comparisons (FITM2, PDRG1, POFUT1, ERGIC3, EDEM2, PIGU, MANBAL and PXMP4). We also noted that other RAS mutant mCRCs had a higher tumour mutation burden than those with KRAS G12C mutations (median 3.05 vs 2.06 muts/Mb, p = 4.2e-3) and that KRAS G12C/other RAS had differing consensus molecular subtype distribution from wildtype colorectal cancer (CRC) (p < 0.0001) but not each other (p = 0.14).

Conclusion

KRAS G12C tumours have similar clinical presentation to other RAS mutant tumours, however, are associated with differential copy number alterations.

Impact of Tumor Location on Patient Outcomes in Small Bowel Cancers

BACKGROUND

Small bowel cancers are rare gastrointestinal malignancies and tumor location impact on outcomes is unclear.

MATERIAL AND METHODS

A retrospective review was performed on stage I to IV small bowel cancer cases from 2000 to 2017 in British Columbia, Canada. Baseline patient characteristics, disease-free survival (DFS) and overall survival (OS) were evaluated by tumor location and systemic therapy use patterns were summarized.

RESULTS

Of 340 patients included, primary tumor distribution was: duodenum (51.2%), ileum (19.1%), jejunum (18.5%), and unspecified (11.2%). Median DFS for stage I to III disease was 37.7, 49.1, and 26.7 months for duodenal, jejunal, and ileal tumors (P = .018). Median OS was 9.6, 35.2, and 20.1 months for duodenal, jejunal, and ileal tumors (P < .0001). Compared to duodenal primaries, both jejunal and ileal tumors were associated with significantly improved OS (HR 0.43, P < .001 for jejunal; HR 0.71, P = .035 for ileal). Adjuvant therapy was given to 21.6% of stage II and 50.6% of stage III cancers. Among patients with metastatic disease, median OS was 4.2, 11.4, and 6.9 months for duodenal, jejunal, and ileal tumors (P = .0019). Jejunal tumors had the best prognosis (HR 0.48, P = .001 vs. duodenum).

CONCLUSION

Survival differences exist when small bowel cancers were assessed by tumor location, and jejunal tumors portended better prognosis overall.

Tumour grade and primary site predict patterns of recurrence and survival in patients with resected gastroenteropancreatic neuroendocrine tumors

BACKGROUND

Patterns of recurrence help to inform surveillance of patients with resected gastroenteropancreatic neuroendocrine tumors (GEP-NETs).

METHODS

Patients with GEP-NETs in British Columbia, Canada (2004-2015) were reviewed. Associations between tumor characteristics, recurrence and survival were analyzed.

RESULTS

Among 759 patients, 41%, 25%, and 17% had grade 1, 2, and 3 disease, respectively. 387 patients had R0/R1 resections, of which 30% recurred (median 25 months). 5-year incidence of recurrence was 22% (grade 1), 46% (grade 2), and 59% (grade 3) (p < 0.001). Grade predicted distant recurrence (Grade 2 HR 1.89, 95% CI 1.16-3.07; p = 0.011; Grade 3 HR 3.29, 95% CI 1.81-5.99; p < 0.001). Compared to small bowel NETs, pancreas NETs had less peritoneal recurrence (OR 0.15, 95% CI 0.03-0.68, p = 0.014). No patients had isolated pulmonary recurrences.

CONCLUSION

Higher grade tumors and pancreatic NETs require more frequent surveillance. Evidence is limited for pulmonary surveillance.

Pancreatic Gastrinoma, Gastrointestinal Stromal Tumor (GIST), Pheochromocytoma, and Hürthle Cell Neoplasm in a Patient with Neurofibromatosis Type 1: A Case Report and Literature Review

BACKGROUND Neurofibromatosis type 1 (NF1) is a multi-tumor syndrome in which affected patients develop malignancies that are rare in the overall population, such as tumors of neural or endocrine origin. CASE REPORT A 67-year-old woman with a clinical diagnosis of NF1 presented with abdominal pain and pneumoperitoneum. She underwent small-bowel resections for a perforated jejunal lesion and a second lesion in the ileum; pathology showed a neurofibroma at the site of the perforation and a 1-cm low-grade GIST, respectively. Additional staging with cross-sectional imaging identified a 3.7-cm pancreatic head mass and a 1.7-cm left adrenal mass; biochemical studies revealed elevated serum gastrin and urinary free metanephrines and catecholamines consistent with pheochromocytoma. Initial surgical management was a left posterior retroperitoneoscopic adrenalectomy. Postoperatively, gallium-68-DOTATOC PET/CT showed uptake in the pancreatic head and a 28-mm left thyroid nodule. Months later, she had an open pancreaticoduodenectomy. Pathology showed pheochromocytoma and a low-grade (G1) gastrinoma involving 2/8 peripancreatic lymph nodes (pT3pN1M0), respectively. Fine-needle aspiration biopsy of the thyroid nodule showed features consistent with a Hürthle cell neoplasm. Genetic testing identified a pathogenic mutation in NF1 and no mutations in BRCA1/2, CDC72, MEN1, or PALB2. The patient continues surveillance, with no evidence of recurrent disease. CONCLUSIONS We report the fifth case of gastrinoma associated with NF1 and the first to arise from the pancreas. This case of a pancreatic neuroendocrine tumor was associated with multiple additional neoplasms. Neuroendocrine tumors found in NF1 should raise suspicion of other malignancies.

Association of a Prophylactic Surgical Approach to Stage IV Small Intestinal Neuroendocrine Tumors With Survival

Importance

Primary tumor resection and mesenteric lymph node dissection in asymptomatic patients with stage IV small intestinal neuroendocrine tumors (SI-NETs) are controversial.

Objective

To determine the association of locoregional surgery (LRS) performed at diagnosis with outcomes in patients with asymptomatic SI-NETs and distant metastases.

Design, Setting, and Participants

This cohort study included asymptomatic patients with stage IV SI-NETs diagnosed from January 1, 1985, through December 31, 2015, and identified using the prospective database of SI-NETs from Uppsala University Hospital, Uppsala, Sweden. Patients included were treated at a tertiary referral center and followed up until May 31, 2016, with data from the Swedish National Patient Register. The 363 patients with stage IV SI-NETs without abdominal symptoms were divided between those who underwent prophylactic up-front surgery within 6 months from diagnosis combined with oncologic treatment (hereafter referred to as LRS group [n = 161]) and those who underwent nonsurgical treatment or delayed surgery as needed combined with oncologic treatment (hereafer referred to as delayed LRS group [n = 202]).

Exposures

Prophylactic up-front surgery within 6 months from diagnosis combined with oncologic treatment vs nonsurgical treatment or delayed surgery as needed combined with oncologic treatment.

Main Outcomes and Measures

Overall survival (OS), length of hospital stay (LOS), postoperative morbidity and mortality, and reoperation rates measured from baseline. Propensity score matching was performed between the 2 groups.

Results

The 363 patients included 173 women (47.7%) and 190 men (52.3%), with a mean (SD) age at diagnosis of 62.4 (11.1) years. Two isonumerical groups with 91 patients in each resulted after propensity score matching. The LRS and delayed LRS groups were comparable in median OS (7.9 years [range, 5.1-10.7 years] vs 7.6 years [range, 5.8-9.5 years]; hazard ratio [HR], 0.98; 95% CI, 0.70-1.37; log-rank P = .93) and cancer-specific survival (7.7 years [range, 4.5-10.8 years] vs 7.6 years [range, 5.6-9.7 years]; HR, 0.99; 95% CI, 0.71-1.40; log-rank P = .99). No difference was found in 30-day mortality (0 patients in both matched groups) or postoperative morbidity (2 [2.2%] vs 1 [1.1%]; P > .99), median LOS (73 days [range, 2-270 days] vs 76 days [range, 0-339 days]; P = .64) or LOS due to local tumor-related symptoms (7.0 days [range, 0-90 days] vs 11.5 days [range, 0-69 days]; P = .81), or incisional hernia repairs (4 patients [4.4%] in both groups; P > .99). Patients in the LRS group underwent more reoperative procedures (13 [14.3%]) compared with those in the delayed LRS group (3 [3.3%]) owing to intestinal obstruction (P < .001).

Conclusions and Relevance

Prophylactic up-front LRS conferred no survival advantage in asymptomatic patients with stage IV SI-NETs. Delayed surgery as needed was comparable in all examined outcomes and was associated with fewer reoperations for intestinal obstruction. The value of a priori LRS in the presence of distant metastases is challenged and needs to be elucidated in a randomized clinical study.

A rare cavernous hemangioma of the adrenal gland

INTRODUCTION

Cavernous hemangiomas of the adrenal gland are rare. We report a case of a cavernous hemangioma of the adrenal gland presenting as an adrenal incidentaloma suspicious for adrenal cortical carcinoma (ACC).

PRESENTATION OF CASE

A 78 year old woman was admitted after a fall. Abdominal computed tomography revealed a large right adrenal lesion with features suspicious for adrenal cortical carcinoma (5.4 cm × 3.3 cm, unilateral, tumor calcifications, average Hounsfield units 55). The tumor was removed intact by a laparoscopic approach and pathology revealed a cavernous hemangioma of the adrenal gland.

DISCUSSION

Adrenal incidentalomas are found in up to 10% of patients undergoing abdominal imaging. Differential diagnosis includes both benign and malignant lesions. Guidelines for removal of adrenal incidentalomas recommend surgery based on functional status, size, and presence of concerning features on diagnostic imaging. Cavernous hemangiomas are rare, benign vascular malformations which can be challenging to distinguish pre-operatively from malignant lesions such as ACC.

CONCLUSION

Cavernous hemangiomas of the adrenal gland are exceedingly rare. These benign tumors have imaging features which may be suggestive of adrenal cortical carcinoma. The treatment of choice is surgical excision due the difficulty of excluding malignancy.

Localized Rho GTPase activation regulates RNA dynamics and compartmentalization in tumor cell protrusions

mRNA trafficking and local protein translation are associated with protrusive cellular domains, such as neuronal growth cones, and deregulated control of protein translation is associated with tumor malignancy. We show here that activated RhoA, but not Rac1, is enriched in pseudopodia of MSV-MDCK-INV tumor cells and that Rho, Rho kinase (ROCK), and myosin II regulate the microtubule-independent targeting of RNA to these tumor cell domains. ROCK inhibition does not affect pseudopodial actin turnover but significantly reduces the dynamics of pseudopodial RNA turnover. Gene array analysis shows that 7.3% of the total genes analyzed exhibited a greater than 1.6-fold difference between the pseudopod and cell body fractions. Of these, only 13.2% (261 genes) are enriched in pseudopodia, suggesting that only a limited number of total cellular mRNAs are enriched in tumor cell protrusions. Comparison of the tumor pseudopod mRNA cohort and a cohort of mRNAs enriched in neuronal processes identified tumor pseudopod-specific signaling networks that were defined by expression of M-Ras and the Shp2 protein phosphatase. Pseudopod expression of M-Ras and Shp2 mRNA were diminished by ROCK inhibition linking pseudopodial Rho/ROCK activation to the localized expression of specific mRNAs. Pseudopodial enrichment for mRNAs involved in protein translation and signaling suggests that local mRNA translation regulates pseudopodial expression of less stable signaling molecules as well as the cellular machinery to translate these mRNAs. Pseudopodial Rho/ROCK activation may impact on tumor cell migration and metastasis by stimulating the pseudopodial translocation of mRNAs and thereby regulating the expression of local signaling cascades.