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Tumor Discovery Sarcomatoid mesothelioma: A case report

and commercialization still occur widely in Asia and many pleural mesothelioma. Unfortunately, Mansfield et al. 18
17
Central and South American countries. In a highly found that compared to patients with other subtypes, fewer
7-9
globalized world with accessible travel, it is critical for patients with SM have complete and partial responses
physicians to recognize and manage mesothelioma, even if to treatment, with response rates recorded at 13.9%
asbestos production is limited in their home nation. and 21.9%, respectively. Novel research into alternative
treatment modalities, including trimodal therapy with
Initial symptoms of SM are often non-specific, most
commonly cough and dyspnea. Many patients are surgery, chemotherapy, and adjuvant radiotherapy, as
well as molecular targeted therapy, is needed to improve
incidentally found to have pleural effusions on imaging. outcomes for patients with SM. 14
Chest wall or back pain are less commonly described in
SM, though they were presenting features in our case. 3,10 4. Conclusion
Much of the morbidity and mortality associated with SM
is due to local disease progression and invasion of critical SM is the rarest main form of mesothelioma, a disease
2
structures in the mediastinum. Previously believed to be that has remained unknown to the public for a long
rare, tumor dissemination in extrapleural and extrathoracic time due to international governmental policies limiting
sites is common, occurring in 87.7% and 55.4% of patients, asbestos production and use. The long latency period
respectively. In lung cancer, however, metastasis to the since exposure, non-specific symptom manifestation, and
11
gastrointestinal tract is exceptionally uncommon, noted in challenges in diagnostics lead to the majority of patients
only ~0.5% of cases. In pleural mesothelioma specifically, presenting with late-stage disease upon diagnosis. During
12
metastasis to the gastrointestinal lumen in the absence of the terminal stage of the disease, local invasion of the
peritoneal disease is rare, with <20 cases reported in the tumor has typically become too extensive for surgical
literature thus far. Most of these cases were caused by resection, and conventional chemotherapy options have
epithelioid mesothelioma, and three resulted from SM. proven unsuccessful in managing SM. Therefore, clinicians
Only one case reported gastric ulcers from metastatic must have high diagnostic suspicion for mesothelioma,
SM, similar to our case. particularly SM, when encountering patients originating
13
from asbestos-producing regions to ensure prompt
Challenges in diagnosing SM include difficulty in diagnosis and treatment and to optimize patient outcomes.
differentiating it from other spindle cell neoplasms and
inconsistent expression of the common tumor markers Acknowledgments
used in immunohistochemistry. 13,14 On biopsy, SM is None.
characterized by spindle-shaped cells and a lack of the typical
glandular structures seen in other types of mesothelioma. Funding
15
However, SM may mimic other neoplasms depending on
the anatomic site involved, namely sarcomatoid carcinoma None.
and intraabdominal synovial sarcoma, which share a Conflict of interest
13
similar histomorphology. Common mesothelial markers
for immunohistochemical studies include calretinin, The authors declare no conflicts of interest.
D2-40, WT-1, and cytokeratin. For SM specifically, staining
is typically positive for cytokeratin and calretinin, but there Author contributions
have been rare cases with negative calretinin expression, Conceptualization: Elizabeth Chiang, Alec B. Rezigh
making diagnosis additionally challenging. 14,16 Investigation: Elizabeth Chiang, Alec B. Rezigh
Management of SM centers around surgical resection Methodology: Elizabeth Chiang
of the tumor and chemotherapy. For resectable tumors, Writing – original draft: Elizabeth Chiang
surgery lessens the tumor burden, relieving dyspnea and Writing – review & editing: All authors
reducing the occurrence of pleural effusions. Neoadjuvant Ethics approval and consent to participate
14
or adjuvant chemotherapy with cisplatin and pemetrexed
is the only Food and Drug Administration-approved The manuscript and patient data were written and collected
combination for the treatment of pleural mesothelioma in accordance with the declaration of Helsinki and our
and remains the sole treatment modality for patients in the institutional ethics guidelines.
United States who are either not candidates for surgery or
have unresectable disease. Globally, immune checkpoint Consent for publication
2,14
inhibitors, such as nivolumab, and anti-angiogenic drugs, We have obtained informed verbal consent from the
such as bevacizumab, have shown efficacy against malignant patient for the publication of this report. The authors have

Volume 3 Issue 4 (2024) 3 doi: 10.36922/td.4420