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

Comparative analysis of immunotherapy responses in small cell lung cancer patients with dermatomyositis

Cancer-associated dermatomyositis (CAD), a paraneoplastic syndrome characterized by dermatomyositis (DM), frequently presents in association with small cell lung cancer (SCLC). Although the advent of immune checkpoint inhibitors (ICIs) has revolutionized cancer treatment, their efficacy and safety in patients with concurrent autoimmune diseases (AD) and malignancies remains uncertain. Several studies have suggested the safe administration of ICIs in patients with AD, indicating that successful cancer therapy can alleviate CAD symptoms. Conversely, other studies have raised concerns about the potential for ICIs to exacerbate AD flares or immune-related adverse events (irAEs). A comparative analysis of two cases from our institution emphasizes the variability in ICI responses among SCLC patients with CAD. One patient, previously reported as a case study, exhibited significant clinical improvement in DM symptoms after ICI administration, whereas the other developed severe exfoliative skin changes and experienced an unfavorable prognosis. This variability emphasizes the need for careful patient selection and close monitoring during ICI treatment. We hypothesized that overweight or obese individuals and those with severe initial skin lesions and elevated lactate dehydrogenase levels are more susceptible to developing irAEs following ICI therapy. Therefore, caution is advised when considering immunotherapy in these patients.

Small cell lung cancer with dermatomyositis: a case report

Dermatomyositis represents an autoimmune disorder characterized by notable skin and muscular manifestations. The annual incidence of dermatomyositis stands at approximately (5~10)/1 million individuals. Notably, patients with malignant tumors exhibit an elevated risk of developing dermatomyositis compared to the general population. However, in cases where dermatomyositis co-occurs with malignancy, the efficacy of hormone therapy alone tends to be suboptimal. Moreover, reports addressing the correlation between tumor treatment and the management of dermatomyositis are scarce. A 60-year-old male patient presented with dermatomyositis, initially manifesting through symptoms such as rash, muscle weakness, and dysphagia. Despite undergoing standard hormone therapy, there was no discernible improvement in the dermatomyositis symptoms. Considering the patient's concomitant troublesome cough, further investigations were conducted, including CT, PET-CT, and pathological biopsy. These assessments confirmed the diagnosis of limited-stage small cell lung cancer (T1cN3M0 IIIB). Notably, in this patient, dermatomyositis was suspected to be a paraneoplastic syndrome associated with small cell lung cancer. Standard chemotherapy and radiotherapy were employed to treat the small cell lung cancer, resulting in partial remission after two treatment cycles. As the malignancy regressed, a notable improvement in dermatomyositis symptoms was observed, subsequently leading to a gradual reduction in the prescribed hormone dosage. In conclusion, we present a comprehensive case study of dermatomyositis as a paraneoplastic syndrome throughout the treatment process. The response to tumor therapy coincided with the amelioration of dermatomyositis symptoms. Therefore, diligent malignancy screening is imperative for patients diagnosed with dermatomyositis.

Two cases of dermatomyositis associated with neuroendocrine tumors

Dermatomyositis is an idiopathic inflammatory myopathy with cutaneous manifestations, which is associated with several types of malignancies, yet it has been rarely linked to neuroendocrine tumors (NETs). Here we report two cases of dermatomyositis associated with NETs of differing primary sites. Case 1: A 46-year-old female presented with a facial rash and proximal muscle weakness of both extremities. Investigations revealed elevated creatine kinase (CK) and positive anti-transcriptional intermediary factor 1-γ antibody (TIF1γ). The patient had been diagnosed with dermatomyositis and underwent a total body CT scan, which revealed prominent mediastinal lymphadenopathy, which a subsequent biopsy determined to be neuroendocrine carcinoma of small cell type. Treatment with high-dose corticosteroids was initiated, in addition to chemotherapy-based oncological management. Case 2: A 54-year-old female presented with a facial rash, progressive dyspnea, and general malaise. Laboratory investigations revealed positive anti-melanoma differentiation-associated gene-5 (MDA5) and positive anti-Ro antibody, with a normal level of creatine kinase (CK). A chest CT scan revealed multiple ground-glass opacities. Despite treatment with high-dose intravenous methylprednisolone, IVIG and an infusion of the anti-IL-6 sarilumab [Kevzara], the patient rapidly deteriorated and was intubated. Within days, the patient developed bowel ischemia and underwent a laparotomy which was then complicated by an invasive infection. This resulted in patient's death. Pathology results from colonic tissue demonstrated an appendiceal neuroendocrine tumor. These cases demonstrate the heterogeneity and complexity of dermatomyositis in association with neuroendocrine tumors.