Lung squamous carcinoma with two paraneoplastic syndromes: dermatomyositis and Lambert-Eaton myasthenic syndrome

Lambert-Eaton Myasthenic Syndrome Recurrence Induced by Pembrolizumab in a Patient with Non-small-cell Lung Cancer

A 73-year-old woman in complete remission from localized small-cell lung cancer associated with Lambert-Eaton myasthenic syndrome (LEMS) 22 years earlier was referred to our hospital and diagnosed with non-small-cell lung cancer. After three courses of pembrolizumab, an immune checkpoint inhibitor, the patient complained of muscle weakness, fatigue, ptosis, and dysarthria. The anti-voltage-gated calcium channel antibody level was elevated, and waxing was observed on a high-frequency repetitive stimulation test using an electromyogram. We diagnosed her with recurrence of LEMS as an immune-related adverse event (irAE) induced by pembrolizumab. After intravenous immunoglobulin therapy, the patient's symptoms improved, and she was discharged.

Dermatomyositis Associated with Lung Cancer: A Brief Review of the Current Literature and Retrospective Single Institution Experience

Dermatomyositis is a rare inflammatory myopathy that is often related to lung cancer. In this retrospective observational study, we analyzed data from patients diagnosed with lung cancer at Soroka University Medical Center between January 2017 and July 2021. A total of 689 patients with lung cancer were included in this study, 97 of whom had small cell lung cancer and 592 had non-small cell lung cancer. We identified a single patient (60-year-old female) who presented with signs and symptoms of dermatomyositis, which was later confirmed to be associated with lung cancer as a paraneoplastic syndrome. Both our study and a recent review of the literature illustrate the temporal link between dermatomyositis and lung cancer, as well as reinforce the need for heightened cancer screenings in DM patients.

Unusual Association of Non-paraneoplastic Variant of Lambert-Eaton Myasthenic Syndrome with Predominant B-cell Inflammatory Myopathy

Introduction: Myasthenia gravis disease (MGD) and inflammatory myopathy (IM) are commonly reported in the literature and usually appear with thymic pathology. Lambert-Eton myasthenic syndrome (LEMS) associated with IM is extremely rare. Case Presentation: We report a 42-year-old female patient who presented with proximal muscle weakness of the upper and lower limbs, normal creatinine kinase (CK) level, and positive acetylcholine and voltage-gated calcium channel receptor antibodies. There were no oculobulbar symptoms and no history of thymoma, and the electrophysiological tests were unremarkable. Muscle biopsy revealed focal perimysial and perivascular inflammation, predominantly B-cell lymphocytes, in a non-necrotizing muscle. Conclusions: LEMS associated with IM, particularly B-cell inflammation, has never been reported in the absence of cancer history. Clinical investigations and myopathological features can help establish the diagnosis.

Evaluation of the Updated Diagnostic Criteria for Paraneoplastic Neurologic Syndromes in China

Background

Recently, the paraneoplastic neurologic syndrome (PNS) diagnostic criteria have received a major update with a new score system over the past 16 years. We aimed to evaluate the diagnostic performance and clinical utility in China.

Methods

An eligible cohort of 113 Chinese patients diagnosed with PNSs from the Second Affiliated Hospital School of Medicine Zhejiang University and published data were enrolled retrospectively. Data including clinical phenotype, antibody type, the presence of cancer, and duration of follow-up were reviewed and re-evaluated to classify the diagnostic levels for the 2004 and 2021 PNS criteria. The performances of these 2 criteria were compared. The critical parameters of antibody and cancer for the updated criteria were further explored.

Results

The cohort consisted of 69 males and 44 females with a median age of 60 years. Limbic encephalitis (23, 20.4%), anti-Hu antibody (32, 28.3%), and small-cell lung cancer (32, 28.3%) were the most common clinical phenotype, detected antibody, and concomitant cancer, respectively. A total of 97 (85.8%) patients were diagnosed with definite PNS according to the 2004 criteria: only 42.3% (41/97) fulfilled the 2021 criteria, while the remaining 40, 14, and 2 re-diagnosed with probable PNS, possible PNS, and non-PNS. The requirement of cancers consistent with antibody and phenotype increased the specificity and thus greatly enhanced the accuracy of the 2021 criteria.

Conclusion

The updated criteria for PNS emphasized the consistency between cancer phenotype and antibody and showed a better diagnostic value. A better diagnostic yield could benefit disease management.

Lambert-Eaton Myasthenic Syndrome and Dermatomyositis With Anti-TIF1-gamma Autoantibody: A Unique Association of Autoimmune Neuromuscular Conditions Without Malignancy

ABSTRACT

Lambert-Eaton myasthenic syndrome (LEMS) is a presynaptic neuromuscular junction disorder, and dermatomyositis (DM) is an idiopathic inflammatory myopathy. LEMS and DM are uncommon conditions that can present similarly and are often associated with autoantibodies. Concomitant LEMS and DM have only been reported a few times, and most of those cases were paraneoplastic. We present the first reported case of a patient with antivoltage gated calcium channel antibody positive LEMS who subsequently developed DM with antitranscription intermediary factor 1-gamma (anti-TIF1-γ) antibodies. Interestingly, both conditions occurred without evidence of malignancy. This diagnosis of LEMS and DM with characteristic clinical, electrodiagnostic, and histopathological evidence led to a beneficial modification of the patient's therapeutic regimen. Due to the fact that overlapping concurrent neuromuscular conditions are rare, a high clinical suspicion is needed to identify, evaluate (including appropriate cancer screenings), and appropriately treat these patients.

Trouble at the junction: When myopathy and myasthenia overlap

Although myopathies and neuromuscular junction disorders are typically distinct, their coexistence has been reported in several inherited and acquired conditions. Affected individuals have variable clinical phenotypes but typically display both a decrement on repetitive nerve stimulation and myopathic findings on muscle biopsy. Inherited causes include myopathies related to mutations in BIN1, DES, DNM2, GMPPB, MTM1, or PLEC and congenital myasthenic syndromes due to mutations in ALG2, ALG14, COL13A1, DOK7, DPAGT1, or GFPT1. Additionally, a decrement due to muscle fiber inexcitability is observed in certain myotonic disorders. The identification of a defect of neuromuscular transmission in an inherited myopathy may assist in establishing a molecular diagnosis and in selecting patients who would benefit from pharmacological correction of this defect. Acquired cases meanwhile stem from the co-occurrence of myasthenia gravis or Lambert-Eaton myasthenic syndrome with an immune-mediated myopathy, which may be due to paraneoplastic disorders or exposure to immune checkpoint inhibitors.

Lambert-Eaton Myasthenic Syndrome Caused by Nivolumab in a Patient with Squamous Cell Lung Cancer

Lambert-Eaton myasthenic syndrome (LEMS) is a representative paraneoplastic neurological syndrome. Recently, nivolumab, an anti-programmed cell death 1 inhibitor, has been approved for advanced non-small-cell lung cancer. Careful attention should be paid to immune-related adverse events (irAEs), including neurotoxicity. We herein report a 73-year-old woman with LEMS that occurred during nivolumab treatment for pulmonary squamous cell carcinoma. After the 20th week of nivolumab, she experienced various neurological symptoms such as ptosis, lower limb weakness, and photophobia. Findings from a nerve conduction study and a positive anti-P/Q-type voltage-gated calcium channel antibody made a diagnosis of LEMS. Pyridostigmine and 3,4-diaminopyridine temporarily improved her symptoms. This was the first case of LEMS as a neurological irAE. LEMS should be considered as a possible neurological irAE.

Ground-glass opacity heralding invasive lung adenocarcinoma with prodromal dermatomyositis: a case report

Background

Dermatomyositis, an inflammatory myopathy with cutaneous involvement, is associated with malignancy and often manifests paraneoplastically. While co-occurrence with small cell carcinoma is well attested, primary lung adenocarcinoma, which may present as focal ground-glass opacification on computed tomography of the thorax, is less frequently coincident.

Case presentation

We report the case of a 72-year-old female patient with dermatomyositis — treated with a combination of prednisone, methotrexate, and intravenous immunoglobulin — and an indolent, subsolid, non-hypermetabolic pulmonary lesion, which was determined to be invasive primary lung adenocarcinoma. Supporting a paraneoplastic basis, immunosuppressive therapy was discontinued following tumor excision without relapse of signs or symptoms of dermatomyositis.

Conclusions

While dermatomyositis prodromal to lung adenocarcinoma is not without precedent, association with an indolent, subsolid lesion has, to the best of our knowledge, not been reported. The case described herein illustrates the importance of maintaining a high index of suspicion for malignancy in the setting of dermatomyositis.

An uncommon manifestation of paraneoplastic cerebellar degeneration in a patient with high grade urothelial, carcinoma with squamous differentiation: A case report and literature review

Background

Paraneoplastic neurological syndromes (PNS) are rare disorders associated with malignant tumours, which are triggered by autoimmune reactions. Paraneoplastic cerebellar degeneration (PCD) is the PNS type most commonly associated with ovarian and breast cancer. Two bladder cancers manifesting in PCD were previously reported. However, the cancers in these cases had poor outcomes.

Case presentation

Here, we present a 68-year old man with history of high-grade papillary urothelial carcinoma of the bladder. The patient suffered from persistent cerebellar ataxia accompanied by bladder cancer recurrence five months after transurethral resection of the bladder tumour (TURBt). Laboratory screening for the specific antibodies of paraneoplastic neurological syndromes revealed no positive results. Symptoms were not remitted after a 7-day-course of high-dose glucocorticoid therapy. To our surprise, the patient recovered fully after laparoscopic radical cystectomy. Postoperative pathology revealed that surgical specimens were urothelial carcinoma in situ (CIS) and squamous cell carcinoma of the bladder. The patient remained asymptomatic and there was no evidence of recurrence after the followup period of 11 months.

Conclusion

To our knowledge, this is the third report of PCD in a patient with bladder cancer. This case showed that tumour resection cured the PCD. To assist clinical evaluation and management, literature regarding basic PNS characteristics and bladder cancers was reviewed.

A rare case of tuberculosis with motor neuron disease

Motor neuron disease (MND) is occasionally aggravated by chronic infection. A misdiagnosed case of tuberculosis with MND is illustrated in a 45-year-old woman who underwent successful VATS wedge excision, which is presented herein. MND in an adult is a rare clinical entity. In order to facilitate the preoperative diagnosis and avoid the misdiagnosis of this disease, more etiological factors need to be considered.