Syndrome of Inappropriate Antidiuretic Hormone Secretion: A Poor Prognosis in Small-cell Lung Cancer

The syndrome of inappropriate antidiuretic hormone associated with nasal and paranasal malignant tumors

PURPOSE

To investigate the clinical characteristics of the syndrome of inappropriate antidiuretic hormone (SIADH) associated with nasal and paranasal malignant tumors.

METHODS

Patients with locally advanced or recurrence/metastatic malignant tumors of the nasal and paranasal sinuses were included. The SIADH was diagnosed according to the diagnostic criteria. The clinical characteristics of SIADH patients were retrospectively analyzed.

RESULTS

Six patients (6/188, 3.2%) met the diagnostic criteria of SIADH, including four olfactory neuroblastoma (4/26, 15.4%), one neuroendocrine carcinoma (1/9, 11.1%), and one squamous cell carcinoma (1/63, 1.6%). Five patients (83.3%) had severe hyponatremia; however, the hyponatremia could be improved by fluid restriction or tolvaptan. Three patients' SIADH were recovered during the chemotherapy and the other three were recovered after the surgery.

CONCLUSION

The incidence of SIADH associated with nasal and paranasal malignant tumors is relatively more common in olfactory neuroblastoma and neuroendocrine carcinoma. The hyponatremia caused by SIADH may be corrected by fluid restriction or tolvaptan, and the SIADH may be recovered through anti-tumor therapy.

Syndrome of Inappropriate Antidiuretic Hormone Secretion as the Initial Presentation in a Patient with Stage I Small-cell Lung Cancer

A 67-year-old man with a history of esophageal cancer resection was referred to our hospital because of nausea and appetite loss. Laboratory findings showed severe hyponatremia and were compatible with syndrome of inappropriate antidiuretic hormone (SIADH) secretion. Chest computed tomography (CT) revealed a nodule measuring 13 mm in the lower lobe of the right lung. Right thoracotomy was performed, and the histopathological diagnosis was small-cell lung cancer (T1bN0M0; Stage 1b). Although SIADH is frequently associated with small-cell lung cancer, it is extremely rare as the initial clinical feature in stage I small-cell lung cancer.

Prevalence and Prognostic Significance of Hyponatremia in Patients With Lung Cancer: Systematic Review and Meta-Analysis

Background: The prevalence of hyponatremia is highly variable among patients with lung cancer. However, its prevalence and prognostic significance in subgroups of patients with lung cancer have not yet been evaluated in a meta-analysis. Methods: We have registered our meta-analysis and review protocol to the PROSPERO International Prospective Register of Systematic Reviews, with the following registration number: CRD42020167013. A systematic search was done in the following sources: MEDLINE, Embase, CENTRAL, Web of Science, ClinicalTrials.gov, a WHO Global Health Library. Results: We identified a total of 8,962 potentially eligible studies, and we included 31 articles in our evaluation. The prevalence of hyponatremia in patients with lung cancer varied between 3 and 94.8% with an average of 25% without any significant differences between the following subgroups: histotype, gender, age, Eastern Cooperative Oncology Group (ECOG) state, and the extent of disease. The overall survival (OS) was significantly lower in hyponatremic compared to normonatremic patients at 10 months [RR.59 (95% CI.47-0.74), p < 0.001] and at 20 months [RR.44 (95% CI.33-0.59), p < 0.001], with worse survival rates in non-small cell lung cancer (NSCLC) [RR.27 (95% CI.12-0.44), p < 0.001] than in small cell lung cancer (SCLC) [RR.42 (95% CI.27-0.57), p < 0.001]. If hyponatremia was corrected, OS at 10 months was significantly higher than in the uncorrected hyponatremia group [RR 1.83 (95% CI 1.37-2.44), p < 0.001], but, at 20 months, no statistically significant difference could be found between these subgroups [RR 2.65 (95% CI.94-7.50), p = 0.067]. Conclusions: Patients with lung cancer diagnosed with hyponatremia, especially patients with NSCLC, seem to have significantly lower survival rates than normonatremic patients. If hyponatremia remains uncorrected, the mortality rates might be even higher.

Small cell carcinoma of the cervix complicated by syndrome of inappropriate antidiuretic hormone secretion: a case report

Small cell carcinoma of the cervix is a rare malignant tumor in the clinical setting. Clinical manifestations of this tumor are mostly similar to those of normal types of cervical cancer. Small cell carcinoma of the cervix only shows symptoms of neuroendocrine tumors, such as syndrome of inappropriate antidiuretic hormone secretion (SIADH). Most of the hyponatremia caused by SIADH can be managed after removal of the cause. Hyponatremia is a predictor of poor prognosis and can be used as an indicator of partial recurrence. We report a case of small cell carcinoma of the cervix complicated by SIADH. Our patient presented with irregular vaginal bleeding after menopause. After one cycle of chemotherapy, there was trembling of the limbs, and a laboratory examination showed low Na⁺ and low Cl⁻ levels. After limited water intake, intravenous hypertonic saline, and intermittent diuretic treatment, the patient’s blood Na⁺ levels returned to normal. After a radical operation, the above-mentioned symptoms disappeared.

A narrative review of progress in diagnosis and treatment of small cell lung cancer patients with hyponatremia

Small cell lung cancer (SCLC) is one of the malignant cancers of lung tumors, and hyponatremia, defined as serum sodium concentration (Na⁺) lower than 135 mmol/L, is the most common complication of solid tumors, with an incidence of up to 18.9% and a negative impact on quality of life in SCLC. As a prognostic index of SCLC, timely monitoring and correcting of hyponatremia is of great clinical significance for prolonging the survival period of patients. In the explore of new drugs for small cell lung cancer, it is necessary to include hyponatremia as an evaluation index in clinical studies. As the occurrence of hyponatremia is sometimes unavoidable owing to SCLC specific neurological characteristics, early monitoring to detect the presence of hyponatremia and timely correction are helpful to improve the prognosis of patients. There are many predisposing factors for hyponatremia, including heterotopia of antidiuretic hormone (ADH), use of platinum-based chemotherapy drugs, and intracranial metastasis, among others. Patients with small cell lung cancer are usually asymptomatic in the early stage, while it is of great significance to find a suitable clinical index to judge whether it is a malignant inducement or not. In the clinical setting, due to different electrolyte levels and therapeutic scheduling for the primary disease, an individualized plan is often made, mainly comprising water restriction, infusion, and medications. This review includes related clinical studies and describes the common symptoms and predisposing factors of hyponatremia in patients with SCLC, and their impact on quality of life and prognosis.

Paraneoplastic syndromes in small cell lung cancer

Paraneoplastic syndromes can commonly occur due to lung cancer, especially small cell lung cancer. Frequently paraneoplastic syndromes can precede the diagnosis of the neoplasm or present with limited stage disease. However, these syndromes can also occur at the time of recurrence or metastasis of disease. This review focuses on the epidemiology, pathogenesis, clinical features, and current management of the most common paraneoplastic syndromes encountered in patients with small cell lung cancer. Manifestations of paraneoplastic syndromes in small cell lung cancer include endocrine syndromes with secretion of excess hormones, and neurologic syndromes due to the production of antibodies causing an autoimmune condition. Recent advances have allowed for greater understanding of these syndromes and for the development of improved diagnostic as well as therapeutic tools. Awareness of paraneoplastic syndromes in small cell lung cancer can lead to an earlier diagnosis and recognition of both the condition and in some cases the disease potentially improving the overall survival and prognosis for patients. Further research examining effective methods to improve recovery from neurologic deficits in patients with a paraneoplastic neurologic illness is warranted.

Survival analysis with regard to PD-L1 and CD155 expression in human small cell lung cancer and a comparison with associated receptors

Immune checkpoints expressed on tumor cells may suppress the cytotoxicity of tumor-infiltrating lymphocytes (TILs) via interaction with their ligands. In the present study, checkpoint proteins and ligands, including programmed death-1 (PD-1), programmed death ligand-1 (PD-L1), cluster of differentiation (CD)155 and T cell immunoreceptor with immunoglobulin and ITIM domains (TIGIT) were systematically analyzed in patients with small cell lung cancer (SCLC). Furthermore their clinicopathological features and survival rates were investigated. Immunohistochemistry was performed in order to analyze the expression of PD-L1, CD155, PD-1 and TIGIT in 60 patients with SCLC, and survival analyses were performed using the Kaplan-Meier method and Cox proportional hazards model. It was reported that CD155/TIGIT and PD-L1/PD-1 were highly expressed on tissues of surgically resected SCLC. High expression levels of PD-L1, CD155 or PD-L1+CD155 were significantly associated with shorter survival. However, high expression levels of PD-1 or TIGIT exhibited no obvious association with shorter survival time. Moreover, patients with SCLC in whom PD-L1 and CD155 levels were highly expressed had the shortest survival rate. Multivariate survival analysis revealed that highly expressed PD-L1 [hazard ratio (HR)=2.55, 95% confidence interval (CI)=1.18–5.51, P=0.017] and CD155 (HR=2.40, 95% CI=1.05–5.50, P=0.038) were independent prognostic factors for overall survival (OS) time in SCLC. In addition, it was reported that TIGIT and PD-1, the receptors of CD155 and PD-L1, respectively, were also constitutively expressed on CD8⁺ TILs and tumor cells in SCLC. High expression levels of PD-L1 and CD155 were independent prognostic factors for OS time in patients with SCLC.

[SMALL CELL PROSTATE CANCER PRODUCING SYNDROME OF INAPPROPRIATE SECRETION OF ANTIDIURETIC HORMONE; A CASE REPORT]

A 73-year-old man with progressive prostate cancer visited our hospital after prostate biopsy performed at another hospital. His serum PSA level was 29.02 ng/ml. CT revealed invasion of the bladder, bilateral ureters, and rectum. Otherwise, there was no evidence of metastasis. Pathological findings showed a poorly differentiated adenocarcinoma (Gleason score 4+5) and small cell carcinoma component. Two months after administering combined androgen blockade therapy, he was admitted due to severe hyponatremia caused by the inappropriate secretion of antidiuretic hormone. Furthermore, CT revealed right ureter metastasis, although the PSA levels remained low. Therefore, the patient was put on fluid restriction and sodium administration. After the patient recovered from hyponatremia, chemotherapy, including VP-16 and CDDP, was initiated. However, CT after two chemotherapy cycles revealed disease progression, with multiple bone metastases. Second-line chemotherapy, including CPT-11 and CDDP, was less effective, and the patient died 9 months after the diagnosis.

Managing hyponatremia in lung cancer: latest evidence and clinical implications

Hyponatremia is the most common electrolyte disorder in lung cancer patients. This condition may be related to many causes including incidental medications, concurrent diseases and side effects of antineoplastic treatments or the disease itself. Although not frequently life-threatening, it is usually associated with prolonged hospitalization, delays in scheduled chemotherapy, worsening of patient performance status and quality of life and may also negatively affect treatment response and survival. Most of the available data focus on thoracic tumors, especially small-cell lung cancer (SCLC), where hyponatremia is frequently related to the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). Few studies specifically focus on non-small cell lung cancer (NSCLC) patients. Hyponatremia treatment needs to be personalized based on severity and duration of sodium serum reduction, extracellular fluid volume and etiology. However, literature data highlight the importance of early correction of the serum concentration levels. To achieve this the main options are fluid restriction, hypertonic saline, loop diuretics, isotonic saline, tolvaptan and urea. The aim of this review is to analyze the role of hyponatremia in lung cancer patients, evaluating causes, diagnosis, management and clinical implications.