Radiation therapy improves survival in rectal small cell cancer - Analysis of Surveillance Epidemiology and End Results (SEER) data

Neoadjuvant chemo-radiotherapy combined with immune checkpoint inhibitors: A case report of rectal small-cell undifferentiated carcinoma achieved pathological complete response

RATIONALE

Small-cell undifferentiated carcinoma (SmCC), as an aggressive malignancy, are most commonly arising in lung. Extrapulmonary SmCC is rare. It was reported that SmCC accounts for only 0.1% to 0.2% of colorectal cancers. Currently, no standard treatment regimen is recommended. Here, we presented a case of SmCC from rectum. The patient achieved pathological complete response (pCR) after surgery, which makes us feel gratified, and we are also eager to share this successful case with more peers to provide more references for clinical decision-making.

PATIENT CONCERNS

A 32-year-old male patient presented himself to our outpatient clinic with defecation difficulty for more than 1 month in November 2021.

DIAGNOSES

Colonoscopy revealed a rectal mass 4 cm from the anal margin. Pelvic magnetic resonance imaging revealed a mass in the rectal wall, consistent with the appearance of rectal carcinoma. Cancer cell was found after several biopsies and the immunohistochemistry indicated rectal SmCC.

INTERVENTIONS

Considering that the patient is very young and the malignancy of SmCC is very high, our treatment plan is also very cautious. Many literatures were also searched, but the literature on rectal SmCC is few and the prognosis is poor. Subsequently, we combined the treatment principles of rectal cancer and small cell lung cancer to develop an individualized treatment plan for patients. The patient received neoadjuvant chemoradiotherapy (nCRT) (short-course radiotherapy: 25 Gy/5 fractions, chemotherapy: etoposide + nedaplatin) combined with immune checkpoint inhibitors (ICIs) (tislelizumab). Then, the patient received laparoscopic radical transabdominal resection of rectal carcinoma with a temporary stoma on June 27, 2022.

OUTCOMES

Postoperative pathology showed that there was chronic inflammation in the rectal mucosa without residual cancer, which meant that the patient achieved pCR after nCRT combined with ICIs. On August 15, 2024, the patient returned to our hospital for review, and no signs of recurrence and metastasis were found. By the time this article is submitted, the patient has survived for more than 35 months.

LESSONS

This is the first to be reported in a rectal SmCC patient who achieved pCR after nCRT combined with ICIs, which may provide supporting data for using this treatment option for rectal SmCC.

Treatment of poorly differentiated neuroendocrine carcinomas of rectum and anus with chemoradiotherapy: a single-centre evaluation

PURPOSE

Poorly differentiated neuroendocrine carcinoma (PDNEC) of the rectum and anus is a rare disease exhibiting aggressive biological behaviour, even if diagnosed early. Currently, there are no agreed standard treatment approaches and management of locally advanced (LA) and metastatic PDNEC usually follows treatments used in pulmonary neuroendocrine carcinomas because of the similarities with small cell lung cancer. The role of surgery in PDNEC is still debated and the benefit of chemoradiotherapy (CRT) is unknown. This report summarises the experiences of CRT application in anorectal PDNEC in a single Danish institution.

METHODS

All patients with PDNEC treated with concomitant CRT between May 2019 and January 2021 at a University hospital in Denmark were evaluated. Demographics, treatment and survival outcomes were collected and analysed.

RESULTS

Six patients were identified. Five patients received radiotherapy with 50.4 Gy/28 fractions, and four were eligible for curative resection after the CRT. Distant metastasis was observed in four patients at diagnosis. Two patients with synchronous liver metastases were treated with RFA, and one received a liver resection. The treatment was well tolerated with limited side effects. The median follow-up time was 17 months (range 10-36 months), and the median duration of response was 11.2 months (range 8.1 to 24.2 months). One patient achieved a complete response.

CONCLUSION

A multimodal treatment approach with CRT in advanced stages of PDNEC in a highly selected patient group is well tolerated and with a high chance of achieving local control and, combined with surgery, even complete response in a single case.

A Review of the Evolving Role of Radiotherapy in the Treatment of Neuroendocrine Neoplasms

BACKGROUND

Neuroendocrine neoplasms (NENs) are rare tumours that develop from neuroendocrine cells in various parts of the body. The management of this disease poses a significant challenge because of the heterogeneous clinical presentation and varying degrees of aggressiveness. A multidisciplinary approach is often required in complex clinical situations. Radiotherapy (RT) plays a key role in managing NETs in both curative and palliative settings.

SUMMARY

In this review, we summarize and discuss recent developments in the field of advanced RT in early-stage, locally advanced, and metastatic NENs. We highlight limitations in current approaches and discuss future potential treatment strategies for patients with NENs.

Extrapulmonary Neuroendocrine Carcinomas: Current Management and Future Perspectives

Neuroendocrine carcinomas (NECs) are poorly differentiated and highly aggressive epithelial neuroendocrine neoplasms. The most common primary site is the lung, but they may arise in every organ. Approximately 37% of extrapulmonary NECs (EP-NECs) occur in the gastroenteropancreatic (GEP) tract, followed by the genitourinary (GU) system and gynecological tract. As a result of their rarity, there is scant evidence to guide treatment recommendations, and a multidisciplinary approach is essential for the management of such patients. Platinum-based chemotherapy currently represents the standard of care for EP-NECs of any site, mirroring the management of small-cell lung cancer (SCLC), but further approaches are still under investigation. Indeed, ongoing trials evaluating targeted therapies, immune checkpoint inhibitors (ICIs), and radionuclide therapy could provide potentially breakthrough therapeutic options. Given the relative dearth of evidence-based literature on these orphan diseases, the aim of this review is to provide an overview of the pathology and current treatment options, as well as to shed light on the most pressing unmet needs in the field.

European Neuroendocrine Tumor Society (ENETS) 2023 guidance paper for digestive neuroendocrine carcinoma

This ENETS guidance paper, developed by a multidisciplinary working group, provides up-to-date and practical advice on the diagnosis and management of digestive neuroendocrine carcinoma, based on recent developments and study results. These recommendations aim to pave the road for more standardized care for our patients resulting in improved outcomes. Prognosis is generally poor for digestive NEC, most are advanced at diagnosis and median survival in metastatic disease is 11-12 months. Surgery can be of benefit for localized disease after extensive preoperative imaging. Carboplatin in combination with etoposide is recommended as first-line treatment for metastatic disease. Irinotecan with fluoropyrimidines has the best evidence as second-line treatment. Immunotherapy plays a minor role in biomarker-unselected patients. Molecular profiling if available is encouraged to identify new targets. More prospective clinical trials are highly needed to fulfil the unmet needs in this field, especially on new predictive and prognostic biomarkers and to improve survival of patients with advanced disease.

Rectal neuroendocrine neoplasms: what the radiologists should know

Neuroendocrine neoplasms of the rectum (R-NENs) are rare; however, their incidence has increased almost threefold in the last few decades. Imaging of R-NENs includes two primary categories: anatomic/morphologic imaging comprised of endoscopic ultrasound (EUS), computed tomography (CT), magnetic resonance imaging (MRI), and functional/molecular imaging comprising of planar scintigraphy, single-photon emission computed tomography (SPECT), and positron emission tomography (PET). The management depends on stage, dimension, atypical features, histological grade, and lymphovascular invasion (LVI). Low-risk local R-NENs can be resected endoscopically, and high-risk or locally advanced neoplasms can be treated with radical surgery and lymphadenectomy and/or chemoradiation. The review article focuses on imaging illustrations and discusses applications of different imaging modalities in diagnosing and managing R-NENs.

Rectal neuroendocrine tumors: Current advances in management, treatment, and surveillance

Rectal neuroendocrine neoplasms (r-NENs) are considered among the most frequent digestive NENs, together with small bowel NENs. Their incidence has increased over the past few years, and this is probably due to the widespread use of endoscopic screening for colorectal cancer and the advanced endoscopic procedures available nowadays. According to the current European Neuroendocrine Tumor Society (ENETS) guidelines, well-differentiated r-NENs smaller than 10 mm should be endoscopically removed in view of their low risk of local and distant invasion. R-NENs larger than 20 mm are candidates for surgical resection because of their high risk of distant spreading and the involvement of the muscularis propria. There is an area of uncertainty regarding tumors between 10 and 20 mm, in which the metastatic risk is intermediate and the endoscopic treatment can be challenging. Once removed, the indications for surveillance are scarce and poorly codified by international guidelines, therefore in this paper, a possible algorithm is proposed.

Evaluation of radical surgical treatment in the management of 58 locally advanced rectal neuroendocrine neoplasms, one multicenter retrospective study

BACKGROUND

Locally advanced rectal neuroendocrine neoplasms (NENs) are rare, and the therapeutic effects of surgery in improving the prognosis have been questioned in previous reports.

MATERIALS AND METHODS

The research included 58 consecutive patients with locally advanced rectal NENs from three Chinese medical centers between 2000 and 2020. All have received radical surgical treatment. The clinicopathological and survival data were collected. Kaplan-Meier methods and a Cox proportional hazards regression model were used to evaluate the prognosis and identify independent prognostic factors.

RESULTS

All patients were followed up for a median period of 36 (2-125) months. Of the 58 patients, 13 (22.4%) had G1 neuroendocrine tumors (NETs), 15 (25.9%) had G2 NETs, 6 (10.3%) had G3 NETs, and the remaining 24 (41.4%) patients had G3 neuroendocrine carcinomas (NECs). The 1-year and 3-year disease-free survival (DFS) rates were 64.5% and 48.8%, respectively. The 1-year and 3-year overall survival (OS) rates were 90.5% and 75.4%, respectively. Univariate analysis demonstrated that tumor differentiation (p = 0.002), gross morphology (p = 0.009), T stage (p = 0.024), and extramural vascular invasion (p = 0.009) were associated with the OS. The subsequent multivariate analysis confirmed that tumor differentiation [hazard ratio (HR) = 6.002, 95% confidence interval (CI): 1.210-29.767, p = 0.028] and gross morphology (HR = 3.438, 95% CI: 1.038-11.382, p = 0.043) were independent prognostic factors affecting the clinical outcomes.

CONCLUSIONS

Rectal NENs are a heterogeneous group of diseases. The survival benefits obtained from surgery vary widely based on the tumor clinicopathological features. Patients with G3 NECs and ulcerative mass are at high risks of poor prognosis.

Small-cell neuroendocrine carcinoma of the rectum - a rare tumor type with poor prognosis: A case report and review of literature

BACKGROUND

Small-cell neuroendocrine carcinoma (SNEC) of the rectum is a rare tumor associated with poor prognosis.

CASE SUMMARY

We report a case of a 77-year-old male who came into our hospital because of blood with his stool. An endoscopy revealed a cauliflower-like neoplasm in his rectum. Imaging examination showed that the lesion in the upper rectum was likely rectal cancer, and there was no evidence of metastasis. The patient was treated with surgery. Pathological examination confirmed SNEC of the rectum and an R0 resection was achieved. However, 1 mo after the operation, the patient developed intestinal and ureteral obstructions due to peritoneal metastases. Finally, the patient died from renal failure.

CONCLUSION

SNEC of the rectum is a high-grade carcinoma with an aggressive phenotype, and surgery should be cautiously considered.

Rectal neuroendocrine carcinoma: case report of a rare entity and perspective review of promising agents

Neuroendocrine neoplasms (NENs) comprise a heterogeneous group of tumours, which can be classified into neuroendocrine tumours (NETs), neuroendocrine carcinomas (NECs) and mixed neuroendocrine non-neuroendocrine neoplasms (MiNENs). To date, there is no consensus regarding the optimal therapy, which usually depends on the primary location and classification, according to morphological features of differentiation and proliferation rates. Nevertheless, multidisciplinary strategies combining medical treatments and locoregional strategies have yielded better efficacy results. Here, we report the case of a patient diagnosed with a nonfunctional rectal NECs with metastatic widespread to pelvic lymph nodes and bilateral lung metastases. The patient received three cycles of platinum-etoposide, concomitantly with palliative radiotherapy. Although CT scan after three cycles showed a significant partial response, there was an early fatal progression only 3 months after having stopped systemic therapy. As formerly described in the literature, this case highlights the aggressive behaviour of NECs, rare tumours that often present in advanced stages at diagnosis. Lately, new insights into the molecular biology of NECs have unveiled the possibility of using novel drugs, such as targeted agents or immunotherapy, in molecularly selected subgroups of patients. In this review, we discuss the current management of this rare entity and provide an overview of the most relevant molecular findings, whilst illustrating the potential value that prescreening panels can offer, searching for actionable targets (MSI/dMMR, PD-L1, BRAF^v600E) to guide therapy with promising agents that could fill a void in this disease.

Comparative analysis of colorectal mixed adenoneuroendocrine carcinoma and adenocarcinoma with neuroendocrine differentiation: a population-based study

BACKGROUND

Colorectal mixed adenoneuroendocrine carcinoma (MANEC) and adenocarcinoma with neuroendocrine differentiation (ANED) are recognized as different tumors pathologically and clinically. In a population-based study, the clinicopathologic characteristics and treatment strategies of the two tumors were comparatively analyzed.

METHODS

Patients with colorectal adenocarcinoma (ADEC), neuroendocrine carcinoma (NEC), MANEC and ANED were identified diagnosis from 2010 to 2014 using the Surveillance, Epidemiology, and End Results (SEER) database. The clinicopathologic data were analyzed by Chi-square test, univariable and multivariable Cox regression. Nomogram was performed to provide a prognostic evaluation for colorectal MANEC and ANED.

RESULTS

Totally 82121 patients were recruited in this cohort. There was no difference between MANEC and ANED in clinicopathologic characteristics and prognosis (P>0.05). The survival data showed that 1-year and 3-year survival rates were 84.70% and 67.83% for ADEC, 66.83% and 51.98% for NEC, and 54.27% and 37.68% for MANEC and ANED, respectively. Stage and surgery were independent prognostic factors of colorectal MANEC/ANED. We also found that the prognosis was significantly different without vs with chemotherapy (P=0.000) in stage III colorectal MANEC/ANED; without vs with surgery (P=0.007), and without vs with chemotherapy (P=0.000) in stage IV colorectal MANEC/ANED. Radiation did nothing for improving the prognosis of colorectal MANEC/ANED in stage III and stage IV (P=0.557, 0.677).

CONCLUSIONS

MANEC and ANED should be merged into the same category pathologically and clinically, and had the poorest prognosis. Stage and surgery were independent prognostic risk factors for colorectal MANEC/ANED. The prognosis of MANEC/ANED could not benefit from radiation.

Neuroendocrine neoplasms of rectum: A management update

The estimated annual incidence of R-NENs is 1.04 per 100,000 persons although the real incidence may be underestimated, as not all R-NEN are systematically reported in registers. Also the prevalence has increased substantially, reflecting the rising incidence and indolent nature of R-NENs, showing the highest prevalence increase among all site of origin of NENs. The size of the tumor reveals the behavior of R-NENs where the risk for metastatic spread increases for lesions > 10 mm. Applying the WHO 2010 grading system to whole NENs originating in the gastroenteropancreatic system, R-NENs are classified as Well-Differentiated Neuroendocrine Tumors (WD-NET), which contain NET G1 and NET G2, and Poorly-Differentiated Carcinomas (PD-NEC) enclosing only G3 neoplasms for which the term carcinoma is applied. The treatment is endoscopic resection in most cases: conventional polypectomy or endoscopic mucosal resection (EMR) for smaller lesions or endoscopic submucosal resection with a ligation device (ESMR-L), cap-assisted EMR (EMR-C) and endoscopic submucosal dissection (ESD). However it is important to know when the endoscopic treatment is not enough, and surgical treatment is indicated, or when the latter could be unnecessary. For PD-NECs, it has recently been demonstrated that chemoradiotherapy is associated with a similar long-term survival to that obtained with surgery. As well, new targeted-agents chemotherapy may be indicated for metastatic WD-NETs.

Conditional survival of patients with hepatocellular carcinoma: results from the Surveillance, Epidemiology, and End Results registry

BACKGROUND

Compared with overall survival, conditional survival is a more relevant measure of prognosis in surviving patients over time. The aim of this study was to describe the conditional survival of patients with hepatocellular carcinoma according to different prognostic variables through an analysis of a national population-based cancer registry.

METHODS

We analyzed data from 3,082 hepatocellular carcinoma patients who were diagnosed between 2004 and 2014.

RESULTS

The conditional overall and cause-specific survival improved from 37.6% to 68.9% and 45% to 79.1%, respectively, in the entire study population. The conditional overall and cause-specific survival improved from 32.6% to 69.3% and 40.1% to 74.8%, respectively, in patients aged 65 to 74 years. The conditional overall and cause-specific survival improved from 8.4% to 44.1% and 12.1% to 66.1%, respectively, in the stage IVB group. The conditional overall and cause-specific survival improved from 32.8% to 71.4% and 40.3% to 78.4%, respectively, in the positive/elevated AFP group.

CONCLUSIONS

Conditional survival exhibited an improved prognosis over time. For hepatocellular carcinoma patients who survived for a specific period of time after diagnosis, more dramatic improvements occurred in patients aged 65-74 years, patients with AJCC stage IVB, and patients with a positive/elevated AFP value.

Prognostic factors of overall survival and cancer-specific survival in patients with resected early-stage rectal adenocarcinoma: a SEER-based study

The benefits of radiotherapy for colorectal cancer are well documented, but the impact of adjuvant radiotherapy on early-stage rectal adenocarcinoma remains unclear. This study aimed to identify predictors of overall survival (OS) and cancer-specific survival (CSS) in patients with stage II rectal adenocarcinoma treated with preoperative or postoperative radiation therapy. Patients with early-stage rectal adenocarcinoma in the postoperative state were identified using the Surveillance, Epidemiology, and End Results database. The primary endpoints were OS and overall CSS. Stage IIA patients without radiotherapy had significantly lower OS and CSS compared with those who received radiation before or after surgery. Stage IIB patients with radiotherapy before surgery had significantly higher OS and CSS compared with patients in the postoperative or no radiotherapy groups. Patients with signet ring cell carcinoma had the poorest OS among all the groups. Multivariable analysis showed that ethnicity (HR, 0.388, p=0.006) and radiation before surgery (HR, 0.614, p=0.006) were favorable prognostic factors for OS, while age (HR, 1.064, p<0.001), race (HR, 1.599, p=0.041), stage IIB (HR, 3.011, p=0.011), and more than one tumor deposit (TD) (HR, 2.300, p=0.001) were unfavorable prognostic factors for OS. Old age (HR, 1.047, p<0.00 L), stage IIB (HR, 8.619, p=0.005), circumferential resection margin between 0.1 mm and 10 mm (HR, 1.529, p=0.039), and more than one TD (HR, 2.688, p=0.001) were unfavorable prognostic factors for CSS. This population-based study identified predictors of OS and CSS in patients with early-stage resected rectal adenocarcinoma, which may help to guide future management of this patient population.