Sarcomatoid Carcinoma of Unknown Primary Origin

Case Presentation

Ann Hematol Oncol. 2020; 7(4): 1294.

Sarcomatoid Carcinoma of Unknown Primary Origin

Silva MC*, Ramôa A, Mendes M and Vasconcelos M

Department of Internal Medicine, Hospital de Braga, Portugal

*Corresponding author: Marta Carvalho Silva, Department of Internal Medicine, Hospital de Braga, Sete Fontes, São Victor, 4710-243 Braga, Portugal

Received: April 18, 2020; Accepted: May 06, 2020; Published: May 13, 2020


Neoplasms of unknown primary origin constitute a group of neoplasms in which the primary site cannot be identified after an exhaustive investigation. Sarcomatoid carcinoma of unknown origin is a very rare entity with nonspecific clinical presentation, frequent systemic dissemination at the moment of diagnosis and an aggressive evolution, so the diagnosis represents a challenge. We present the case of a patient who resorted to the emergency service with a neurological deficit as clinical presentation of a disseminated neoplasm. The complementary diagnostic tests performed demonstrated diffuse metastasis in brain, liver, adrenals, bone and muscles and immunohistochemistry examination of a pulmonary nodule revealed the presence of differentiation markers of epithelial lineage consistent with sarcomatoid carcinoma. Initially a pulmonary origin of the tumor was considered more likely, however, despite testing several specific organ markers it was not possible to confirm this hypothesis nor to determine the primary origin of the tumor because the patient died a month after admission due to severe digestive bleeding resulting from gastric metastasis.

Keywords: Unknown sarcomatoid carcinoma

Case Presentation

Neoplasms of unknown primary origin are a heterogeneous group of tumors in which the primary site cannot be identified after a thorough investigation [1,2]. Sarcomatoid carcinoma of unknown primary neoplasm is a very rare entity, so there are few published data on its clinical presentation, characteristic histopathological findings, approach or treatment [1,3]. The clinical presentation is nonspecific with frequent systemic metastasis at diagnosis and a very aggressive evolution with significant low survival rates [1,4]. The diagnosis is characterized by a great difficulty where a correlation between clinical, histological and imaging data is required and where immunohistochemistry is the gold standard by using specific markers of cell and organ lineage that allow the identification of the primary tumor type and site [2,3].

We present the case of a 63-year-old man with a history of arterial hypertension, diabetes, dyslipidemia and smoking habits. He turned to the Emergency Service (ER) due to a decrease of strength and hypoesthesia of the left lower limb with a month of evolution and significant worsening on that day which made walking impossible. He also referred right tempo parietal headache for several days. He denied fever, sweating, anorexia, weight loss, vomiting or other complaints. He performed head Computed Tomography (CT) that revealed multiple expansive lesions with vasogenic edema corresponding to probable secondary tumor lesions (Figure 1). It was followed by a chest, abdominal and pelvic CT scan that showed an irregular shaped nodular lesion in the apical-posterior segment of the left upper lung lobe with 6mm in diameter, 3 micronodules in the anterior segment of the same pulmonary lobe and an adenopathic conglomerate in the pulmonary left hilum with 38X24mm. Seven nodular lesions of secondary nature were also identified distributed over both hepatic lobes as well as in both adrenals. He was admitted to the internal medicine service to study a metastatic neoplasm of unknown primary origin. Analytically he had leucocytosis (23000) neutrophilia and increased C-reactive protein without other major changes. A bronchofibroscopy was performed where an irregular and hypervascularized endobronquial mass was observed in the upper division of the upper lobar bronchus consistent with direct signs of a tumor (Figure 2) and a biopsy was performed. A liver nodule biopsy was also done which proved to be unrepresentative. Positron tomography confirmed the previous findings and detected catching lesions in the sinus of the left buttock muscles and diffuses bone metastasis compatible with an high-metabolic neoplastic pathology. He underwent treatment with dexamethasone and painkillers with a slight improvement in pain complaints and neurological deficits. At discharge he presented liver cytolysis and cholestasis, absent at the admission. He was referred to the outpatient pulmonology consultation to perform a complementary study on the suspicion of a primary pulmonary lesion. The case was discussed in a multidisciplinary consultation group that proposed the repetition of the liver nodule biopsy and treatment with palliative holocranial radiotherapy that was performed with good tolerance. Subsequently the result of the pulmonary nodule biopsy was available whose immunohistochemical study demonstrated expression of MNF116 neoplastic cells, focal expression of CK7 and GATA3, membrane expression of CD138 and absense of TTF1, Napsin-A, p40, Synaptophysin and SOX10, revealing a carcinoma with an unusual phenotype in lung neoplasms, so it was suggested that the pulmonary nodule was a metastatic lesion. The second liver nodule biopsy was also inconclusive. The patient maintained a follow-up in Pulmonology despite histological exams beiing inconclusive and was awaiting for a new group consultation to consider systemic treatment with vinorelbine. About a month after admission he went to the ER for epigastric pain, dark vomiting and dark stools. He underwent an upper digestive endoscopy which revealed multiple [5-10] ulcerated lesions with a crater aspect and size between 5-20mm in the gastric mucosa, suggestive of metastatic lesions (Figure 3). A few hours after the exam he had an episode of abundant hematemesis that lead to his death. Histological examination of gastric lesions made available posterior showed involvement of the mucosa by a neoplasm with characteristics overlapping those observed in the histological examination of the pulmonary nodule concluding that it was a sarcomatoid carcinoma.