Genomic Profiling and Clinicopathological Characteristics of Neuroendocrine Tumors of the Lung in East Asian Patients

The First Case Report of Effective Treatment With Sotorasib for Metastatic Atypical Lung Carcinoid Harboring KRAS G12C Mutation and Aggressive Disseminated Lung Metastasis: A Case Report

Pulmonary neuroendocrine tumors are rare, accounting for approximately 1% to 2% of lung cancers. Atypical carcinoids account for approximately 10% of pulmonary neuroendocrine tumors and are categorized as moderately malignant. Treatment options for advanced-stage atypical carcinoids include everolimus, cytotoxic anticancer agents, and peptide receptor radionuclide therapy. In this report, we present the first case of KRAS G12C mutation-positive atypical carcinoid that was successfully treated with sotorasib. Therapeutically important mutations observed in non-small cell lung cancer are seldom found in atypical carcinoid tumors. Nonetheless, it is worthwhile to search for genetic mutations in atypical carcinoid tumors, considering the potential for molecular targeted therapy to be effective in their treatment as well.

Percutaneous computed tomography-guided core needle biopsy can be used to histologically confirm the clinical features and long-term prognosis of pulmonary neuroendocrine neoplasms

PURPOSE

We investigated the clinical features and prognosis outcomes of pulmonary neuroendocrine neoplasms (PNENs) which were histologically confirmed after percutaneous computed tomography-guided core needle biopsy (PCT-CNB).

MATERIALS AND METHODS

We retrospectively investigated 173 patients who had PNENs which were histologically confirmed after PCT-CNB; patients were split into low and intermediate-grade neuroendocrine tumor (LIGNET) (typical carcinoid (TC) and atypical carcinoid (AC)) and high-grade neuroendocrine carcinoma-tumor (HGNEC) groups. In this latter group, patients were further subdivided into large-cell neuroendocrine carcinoma (LCNEC), small-cell lung cancer (SCLC), and high-grade neuroendocrine carcinoma-not otherwise specified (HGNEC-NOS) groups. Complications after biopsy were recorded. We also assessed overall survival (OS) rates using Kaplan-Meier curves, with prognostic factors determined using univariate and multivariate analyses.

RESULTS

Complications were mainly pneumothorax (22.5; 39/173 patients), chest tube placement (4.0; 7/173 patients), and pulmonary bleeding (33.5%; 58/173 procedures)-no patient mortality was recorded. Definitive diagnoses were ascribed to 102 SCLC, 10 LCNEC, 43 HGNEC-NOS, 7 TC, and 11 AC patients. The 1- and 3-year OS rates in the LIGNET group were 87.5% and 68.1%, respectively, and 59.2 and 20.9% in the HGNEC group, respectively these data were statistically significant (P = 0.010). For SCLC, 1- and 3-year OS rates were 63.3 and 22.3%, 30.0 and 10.0% for LCNEC, and 53.3% and 20.1% for HGNEC-NOS, respectively (P = 0.031). Independent prognostic factors for OS included disease type and distant metastasis.

CONCLUSION

PNENs may be pathologically diagnosed using PCT-CNB. While differential diagnoses between LCNEC and SCLC are problematic in some patients, a HGNEC-NOS diagnosis was ascribed and PCT-CNB samples were shown to predict NEN OS rates.

Two case reports: EML4-ALK rearrangement large cell neuroendocrine carcinoma and literature review

Anaplastic lymphoma kinase gene (ALK) rearrangement is present in only approximately 5% of non-small cell lung cancers (NSCLCs) and is scarce in LCNEC patients. The conventional first-line treatment options are chemotherapy combined with immunotherapy or chemotherapy followed by palliative radiotherapy. In this report, we present two cases of metastatic LCNEC with EML4-ALK fusion that were treated with ALK-TKI inhibitors and demonstrated a rapid therapeutic response. Both patients were nonsmoking women who declined cytotoxic chemotherapy, underwent Next-Generation Sequencing (NGS), and confirmed EML4-ALK fusion. They were treated with alectinib as first-line therapy, and the tumors showed significant shrinkage after two months, achieving a PR (defined as a more than 30% decrease in the sum of maximal dimensions). The PFS was 22 months and 32 months, respectively, until the last follow-up. A systematic review of all previously reported cases of LCNEC with ALK mutations identified only 21 cases. These cases were characterized by being female (71.4%), nonsmoking (85.7%), diagnosed at a relatively young age (median age 51.1), and stage IV (89.5%), with an overall response rate (ORR) of 90.5%. PFS and OS were significantly longer than those treated with conventional chemotherapy/immunotherapy. Based on the clinical characteristics and the effective therapeutic outcomes with ALK inhibitors in LCNEC patients with ALK fusion, we recommend routine ALK IHC (economical, affordable, and convenient, but with higher false positives) as a screening method in advanced LCNEC patients, particularly nonsmoking females or those who are not candidates for or unwilling to undergo cytotoxic chemotherapy. Further molecular profiling is necessary to confirm these potential beneficiaries. We suggest TKI inhibitors as the first-line treatment for metastatic LCNEC with ALK fusion. Additional studies on larger cohorts are required to assess the prevalence of ALK gene fusions and their sensitivity to various ALK inhibitors.

A case of bilateral synchronous double primary lung cancer secondary to bladder cancer: From the next-generation sequencing prospect

One year following bladder cancer surgery, a 65-year-old man had computed tomography (CT) that revealed bilateral pulmonary nodules. Pulmonary wedge resections were performed after the nodules were found to grow in follow-up. Unusually, we found that these two lesions were not homologous, nor were they metastases from prior bladder cancer, and therefore, synchronous double primary lung cancer (sDPLC) was diagnosed. The immunohistochemical findings excluded the possibility of bladder cancer metastasis, but could not determine whether they were from the same source. Next generation sequencing (NGS) supported the diagnosis sDPLC because they amply demonstrated the two sources' distinct origins. Finally, after discussion with pathologists, this patient was diagnosed as small cell lung carcinoma (SCLC) and received postoperative EP chemotherapy. We also documented a few rather uncommon alterations that might serve as a foundation for further investigation. This case suggests that in addition to immunohistochemical, NGS is also helpful to clarify the etiology and refine the pathological classification of tumors, which has guiding significance for the establishment of precise diagnosis and optimal treatment.

Pulmonary neuroendocrine tumors: study of 266 cases focusing on clinicopathological characteristics, immunophenotype, and prognosis

OBJECTIVE

Pulmonary neuroendocrine tumors (PNETs) consist of small-cell lung cancer (SCLC), large-cell neuroendocrine carcinoma (LCNEC), typical carcinoid (TC), and atypical carcinoid (AC). We aimed to analyze the immunophenotypic, metastatic, and prognostic risk factors for PNETs.

MATERIALS AND METHODS

A total of 266 patients with PNETs were enrolled, including 219 patients with SCLC, 18 patients with LCNEC, 11 patients with TC, and 18 patients with AC. Clinicopathological characteristics and immunophenotypes were compared among the subtypes of PNETs. Risk factors for metastasis, progression-free survival (PFS), and overall survival (OS) were analyzed.

RESULTS

Thyroid transcription factor-1 (TTF-1) and the Ki-67 index were significantly different among subtypes of PNETs (all P < 0.05). Smoking (OR, 2.633; P = 0.031), high pretreatment carcinoembryonic antigen (CEA > 5 ng/ml: OR, 3.084; P = 0.014), and poorly differentiated pathotypes (P = 0.001) were independent risk factors for lymph-node metastasis. Smoking (OR, 2.071; P = 0.027) and high pretreatment CEA (OR, 2.260; P = 0.007) were independent risk factors for distant metastasis. Results of the multivariate Cox regression model showed pretreatment CEA (HR, 1.674; P = 0.008) and lymphocyte-monocyte ratio (LMR) (HR = 0.478, P = 0.007) were significantly associated with PFS; BMI (P = 0.031), lymph-node metastasis (HR = 4.534, P = 0.001), poorly differentiated pathotypes (P = 0.015), platelet-lymphocyte ratio (PLR) (HR = 2.305, P = 0.004), and LMR (HR = 0.524, P = 0.045) were significantly associated with OS.

CONCLUSIONS

PNETs are a group of highly heterogeneous tumors with different clinical manifestations, pathological features, and prognoses. Knowing clinicopathological characteristics and immunophenotypes of PNETs is significant for diagnosis. Pretreatment PLR, LMR, and CEA have certain value in the prognosis of PNETs.

Survival Benefit of Adjuvant Chemotherapy in Pulmonary Carcinoid Tumors

Pulmonary carcinoid tumors are a rare subtype of neuroendocrine cell tumor found in approximately 1–2% of lung cancers. Management is primarily through surgical resection, with limited benefit of adjuvant therapy in the clinical setting. Genomic profiling is in the nascent stages to molecularly classify these tumors, but there are promising insights for future targeted therapy. A total of 80 abstracts were analyzed for further review with 11 included in our final analysis. Only 4 of the 11 reviewed in depth provided statistical analysis. We evaluated PFS, OS, 1- and 5-year survival as mentioned in the studies. Nodal and KI67 status were also analyzed. Based on the current literature, there is no definitive evidence that adjuvant chemotherapy after resection confers a survival benefit in typical or atypical carcinoids.