Small Cell Carcinoma of Unknown Primary

Emerging Treatment Options for Neuroendocrine Neoplasms of Unknown Primary Origin: Current Evidence and Future Perspectives

Among neuroendocrine neoplasms (NENs), a non-negligible proportion (9-22%) is represented by sufferers of NENs of unknown primary origin (UPO), a poor prognostic group with largely unmet clinical needs. In the absence of standard therapeutic algorithms, current guidelines suggest that the treatment of UPO-NENs should be based on tumor clinical-pathological characteristics, disease burden, and patient conditions. Chemotherapy represents the backbone for the treatment of high-grade poorly differentiated UPO-NENs, usually providing deep but short-lasting responses. Conversely, the spectrum of available systemic therapy options for well-differentiated UPO-NENs may range from somatostatin analogs in indolent low-grade tumors, to peptide receptor radioligand therapy, tyrosine kinase inhibitors (TKIs), or chemotherapy for more aggressive tumors or in case of high disease burden. In recent years, molecular profiling has provided deep insights into the molecular landscape of UPO-NENs, with both diagnostic and therapeutic implications. Although preliminary, interesting activity data have been provided about upfront chemoimmunotherapy, the use of immune checkpoint inhibitors (ICIs), and the combination of ICIs plus TKIs in this setting. Here, we review the literature from the last 30 years to examine the available evidence about the treatment of UPO-NENs, with a particular focus on future perspectives, including the expanding scenario of targeted agents in this setting.

Advanced gastric cancer with metachronous intracranial oligometastases without recurrence after multidisciplinary team discussion and comprehensive treatment: a case report

This article describes the process of multidisciplinary team (MDT) discussion and comprehensive treatment of a case of advanced gastric cancer that tested positive for programmed death ligand 1 (PD-L1). During diagnosis, the patient presented with advanced gastric cancer and numerous unresectable metastases in the lesser omental lymph nodes, both lungs, liver, and left parietal occipital lobe. A meeting was arranged for the departments of oncology, gastrointestinal surgery, radiotherapy, imaging, and pathology to discuss the case. Initially, the patient had a partial response to the first-line treatment, which was a combination of pembrolizumab and chemotherapy. However, after nineteen months, the patient presented with a metachronous isolated lesion in the left frontal lobe. After mutual agreement among the oncology, brain surgery, gastrointestinal surgery, radiotherapy, imaging, and pathology departments, the intracranial lesion underwent resection. Following this, the operation was supplemented by stereotactic radiation therapy (SRT) and whole-brain radiation therapy (WBRT). The patient showed excellent signs of recovery after the operation, and her general condition remained favorable after 16 months of follow-up. Nonetheless, the outlook for patients facing advanced-stage gastric cancer remains distressing. Through multidisciplinary team (MDT) discussions, patients diagnosed with advanced gastric cancer can receive standardized diagnostic and treatment approaches to develop reasonable and personalized comprehensive treatment plans. Such plans help to improve the quality of life of patients and effectively prolong their survival time.

Small cell carcinoma with neuroendocrine differentiation of subglottic larynx- a case report

Small cell cancer (SCC) is a neuroendocrine neoplasm, which is most frequently found in the lungs. Extrapulmonary location of SCC is rare and may involve 2.5-5% of SCCs. We present a case of a 31-year-old male patient with an extremely uncommon subglottic SCC. The patient was qualified for a radical sequential chemoradiotherapy. After treatment, patient's condition suggested complete remission. Recurrence was detected one year later, and the disease rapidly progressed, despite a second line chemotherapy. The patient died 29 months after initial diagnosis. This case aims to raise awareness on the aggressive laryngeal SCC and its good response to first line chemotherapy composed of cisplatin and etoposide, followed by radiotherapy.

Primary Hepatic Small-Cell Carcinoma Developed during Antiviral Treatment for Chronic Hepatitis B

Previously reported cases of primary hepatic small-cell carcinoma were all detected at progressed state with associated symptoms. Therefore, the natural course of primary hepatic small-cell carcinoma remains unknown. This case shows the natural course of primary hepatic small-cell carcinoma. We detected a 1.2 cm hypodense nodule 6 months ago in a patient with cirrhosis who had been taking entecavir. It was suspected to be a regenerating or degenerating nodule. Three months later, liver computed tomography (CT) revealed that the mass was increased to 2.1 cm with the same characteristics. The patient wanted to do a follow-up CT scan after 3 months instead of a biopsy. Another 3 months later, the mass was markedly increased, involving the whole left lobe and was confirmed as small-cell carcinoma on biopsy. Here, we report the first case of primary hepatic small-cell carcinoma developed during treatment for chronic hepatitis B with cirrhosis.

A case of occult intrahepatic cholangiocarcinoma diagnosed by autopsy

Cancer of unknown primary is associated with unknown biology and dismal prognosis. The most common primary sites of cancer of unknown primary were usually the lungs in autopsy studies, and intrahepatic cholangiocarcinoma is rare. We describe the case of a 57-year-old male patient with systemic lymph node metastasis. Imaging examination failed to reveal primary cancer; however, immunostaining of cytokeratins 7, 19, and 20 of a metastatic axillary lymph node suggested a pancreaticobiliary cancer as a primary lesion. He died of liver abscess and sepsis, and then, autopsy indicated occult intrahepatic cholangiocarcinoma. We discuss the clinical course of this rare cholangiocarcinoma including the diagnostic procedure and also present a review of the English literature regarding patients with cancer of unknown primary.

Mediastinal small cell carcinoma: a unique clinical entity?

PURPOSE

Mediastinal small cell carcinoma (MSCC) is a rare tumor with limited published literature. In view of diagnostic confusion pertaining to this tumor, we investigated its origin, clinical features, management and survival.

METHODS

Clinical data of MSCC patients were retrospectively reviewed. Eligible patients showed pathologically proven small cell carcinoma (SCC) with the primary lesions confined to the mediastinum. Survival information was collected through follow-up studies.

RESULTS

Among 25 MSCC patients identified, 22 were classified to have limited disease (LD), while 3 were with extensive disease (ED). The 5 patients (20%) underwent surgery and 20 patients (80%) underwent non-surgical treatment. The 4 patients with LD MSCC received chemotherapy alone, while 13 of them received chemoradiotherapy. Overall median survival time (MST) of all patients was 22 months, and the 1-, 3- and 5-year overall survival rates were 67.4, 16.8, and 8.4%, respectively. The MST of LD and ED patients separately was 23 and 8 months, respectively, with significant difference (P = 0.005). But, the MST of patients who received surgical and non-surgical treatment was 25 and 21 months, respectively, with no significant difference (P = 0.757). The MST of LD patients receiving chemotherapy and chemoradiotherapy was 12 and 29 months, respectively, but somehow did not show significant difference (P = 0.482).

CONCLUSIONS

Our data suggested that MSCC may be a separate clinical entity like extrapulmonary small cell carcinomas (EPSCCs). Despite, multimodal treatment is currently the main treatment option, but for patients with LD MSCC, chemoradiotherapy is recommended to be preferred treatment modality.

Small cell neuroendocrine carcinoma of larynx: case series and literature review

Background:

Primary small cell neuroendocrine carcinoma of larynx is a rare, aggressive type of malignancy. As only about 200 cases worldwide have been reported, any larger institutional experience is valuable. This study reports our experience in managing this rare entity.

Methods:

Of the nine patients identified, three had metastatic cancer at the time of diagnosis. Four patients underwent radical treatment: one was managed surgically followed by adjuvant chemotherapy and consolidation radiotherapy; the remaining three were treated with neoadjuvant chemotherapy and definitive radiotherapy.

Results:

Of the 4 patients treated with radical intent, 1 was alive and disease free after 99 months, 2 died of metastatic disease after 22 and 26 months, and 1 was alive after 20 months with a diagnosis of recurrent disease.

Conclusion:

Our relatively small number of patients confirms other centres' experiences. This cancer has a poorer prognosis than most other head and neck cancers. Although the logistics would be challenging, there is a need for international multicentre trials for this disease modelled on those performed for other cancers, as has been done for paediatric malignancies.

Imaging features of extrapulmonary small cell carcinoma

Small cell carcinoma accounts for approximately 20% of lung cancers; however, it rarely occurs at other sites. Extrapulmonary small cell carcinoma (EPSCC) is notoriously aggressive with a strong propensity for both regional and distant spread. The majority of the literature on these uncommon tumours is from a clinicopathological viewpoint with a relative paucity of detail regarding the radiological findings. This review will focus on the imaging features of EPSCC in its predominant sites of origin: the gastrointestinal tract, genitourinary tract, head, neck, and breast. We will also discuss the role of positron-emission tomography (PET)/computed tomography (CT) in the staging of EPSCC.

Feasibility and efficacy of combined cisplatin and irinotecan chemotherapy for poorly differentiated neuroendocrine carcinomas

OBJECTIVE

No standard treatment has been established for poorly differentiated neuroendocrine carcinoma; the usual recommended treatment is based on the strategy for small cell lung carcinoma. The aim of this study was to evaluate the response of poorly differentiated neuroendocrine carcinoma to the combination of irinotecan and cisplatin in one institution.

METHODS

We retrospectively reviewed 50 poorly differentiated neuroendocrine carcinoma patients treated from September 2005 to April 2011 in our institution. Patients were divided into two stages: limited disease or extensive disease. Forty-four patients received the combination chemotherapy of irinotecan and cisplatin, consisting of 4-week cycles of 60 mg/m(2) irinotecan on days 1, 8, 15 and 60 mg/m(2) cisplatin on day 1.

RESULTS AND CONCLUSION

Median age was 60 years. Median follow-up time was 11.4 months. Overall survival did not reach the median, and 1-year overall survival was 67%. The response rate was 50% (64% at first line), and progression-free survival was 4.8 months (7.3 months at first line). Grade 3-4 hematologic adverse events were seen in 29 patients (66%) and Grade 3-4 non-hematologic adverse events were seen in 20 patients (45%), but no patients died of adverse events. Multivariate analysis showed a statistically significant relationship with neuron-specific enolase elevation and poor overall survival (P= 0.016, hazard ratio 6.261, 95% confidence interval). The combination chemotherapy of irinotecan and cisplatin is moderately effective and feasible, and it should be considered as a treatment option for poorly differentiated neuroendocrine carcinoma.

Neuroendocrine carcinoma of unknown primary: a systematic review of the literature and a comparative study with other neuroendocrine tumors

INTRODUCTION

Neuroendocrine carcinomas of unknown primary (NCUP) represent a specific subset with relatively favorable prognosis. Data on biology, management and outcome of NCUP patients have not been systematically reviewed neither compared to those of neuroendocrine tumors of known primary.

PATIENTS AND METHODS

We systematically reviewed all publications studying neuroendocrine CUP patients and presented a single center retrospective patient series. In addition, we analyzed and specified the similarities and/or differences between NCUP and other neuroendocrine malignancies.

RESULTS

Five hundred patients with NCUP constituted a heterogeneous cohort in terms of histology, grade, anatomic site and tumor biology in published series and were managed mostly with platinum-based regimens. Among 294 patients with available outcome data, a median survival of 15.5 months (range 11.6-40) was observed. Comparative analysis with neuroendocrine solid tumors (NET) revealed that poorly-differentiated NCUP share an aggressive natural history and a dismal prognosis similar to high grade pulmonary and extrapulmonary neuroendocrine carcinomas (Large Cell Neuroendocrine bronchial Carcinomas, LCNEC and poorly differentiated gastroenteropancreatic tumors, GEP-NET). Well differentiated NCUP reveal a more indolent course with a survival range resembling that of typical and atypical pulmonary carcinoids, well differentiated gastrointestinal NETs and limited small cell lung carcinomas.

CONCLUSION

No evidence for distinct biology or outcome of NCUP patients emerged when histological grade was matched for known primary NETs. The high heterogeneity of the NCUP subgroup limits the potential for identification of reliable prognosticators and hinders development of novel targeted therapies.

Small cell carcinoma originating from the cavernous sinus

BACKGROUND

We report a rare case of small cell carcinoma originating from the right cavernous sinus in a 55-year-old male. The patient had sudden onset of right abducens palsy following right oculomotor palsy.

METHODS

Post-contrast T1-weighted MRI revealed a mass lesion of 3-cm maximum size occupying the right cavernous sinus and extending to the right middle cranial fossa. After biopsy via the frontozygomatic approach, one radiosurgery treatment was followed by four cycles of chemotherapy (cisplatin together with VP-16 therapy), after which the lesion diminished dramatically in size.

RESULTS

Complete remission has currently been achieved. The patient recovered from the extraocular muscle paresis and returned to his previous work. Although it is considered possible that small cell carcinoma can occur wherever neuroendocrine cells exist, a lesion originating in the cranium is extremely rare. To the best of our knowledge, this is the first report of small cell carcinoma of intracranial origin.

Clinical and therapeutic aspects of extrapulmonary small cell carcinoma

Extrapulmonary small cell carcinoma (EPSCC) is usually treated similarly to small cell lung cancer. Differences in aetiology, clinical course, frequency of brain metastases, and survival, however, warrant a differential therapeutic approach. In this review, we focus on the treatment of the most predominant sites of origin of EPSCC; the gastrointestinal tract, the genitourinary tract, the head and neck region, and small cell carcinoma of unknown primary. Furthermore we review the available data concerning the controversial issue of prophylactic cranial irradiation (PCI) after optimal treatment of EPSCC. We found in the literature a significant lower incidence of brain metastases in EPSCC as compared to pulmonary small cell carcinoma when PCI is omitted and therefore we do not recommend PCI. An exception is EPSCC originating from the head and neck region which is associated with a higher incidence of brain metastasis, justifying addition of PCI.

Extrapulmonary small cell carcinoma: involvement of the brain without evidence of extracranial malignancy by serial PET/CT scans

Background

Extrapulmonary small cell carcinoma (EPSCC) involving the brain is a rare manifestation of an uncommon tumor type.

Case presentation

We report a 59 year-old Caucasian female diagnosed with an EPSCC involving the left parietal lobe without detectable extracranial primary tumor followed by serial positron emission tomography/computed tomography (PET/CT) imaging. Histopathological examination at both initial presentation and recurrence revealed small cell carcinoma. Serial PET/CT scans of the entire body failed to reveal any extracranial [¹⁸F]2-fluoro-2-deoxy-D-glucose (FDG) avid lesions at either diagnosis or follow-up.

Conclusion

Chemotherapy may show a transient response in the treatment of EPSCC. Further studies are needed to help identify optimal treatment strategies. Combination PET/CT technology may be a useful tool to monitor EPSCC and assess for an occult primary malignancy.