Squamous Cell Carcinoma of the Neck with Second Primary Malignancy vs. Metastasis: A Case Study

Although head and neck squamous cell carcinoma (HNSCC) with a second primary malignancy (SPM) are considered rare, 25-33% of deaths in patients with HNSCC are due to SPMs. This statistic underscores the significance of diagnosing SPMs accurately in the management and treatment of HNSCC. A 56 year old male presents with a large neck mass, dysphagia, and a raspy voice. A magnetic resonance imaging (MRI) of the head and neck displayed a 9x7 cm right neck mass. Therefore, a laryngoscopy with biopsy was performed to assess the severity of the neoplasm. The patient underwent a panendoscopy to exclude any evidence of additional primary malignancies in the neck, larynx, and esophagus. A staging computed tomography (CT) scan of the chest, abdomen, and pelvis revealed two hepatic lesions. These results were inconclusive in defining the lesions as metastases or SPMs, so a triple-phase CT scan of the abdomen was utilized to help explain the origin of the lesions. A liver biopsy was indicated following imaging results of the triple-phase CT. An alpha-fetoprotein level was also measured. The laryngoscopy with biopsy showed evidence of translaryngeal extension and moderately differentiated squamous cell carcinoma (SCC) at the base of the tongue. The CT scan revealed two hepatic lesions: a heterogeneous irregular 6.2x7.1 cm mass within the superomedial right and left hepatic lobes and an ill-defined 4.2x5.4 cm mass at the porta hepatis, which was incompletely visualized. The triple-phase CT scan showed the 6.2x7.1 cm mass as an arterially enhancing lesion with imaging characteristics consistent of hepatocellular carcinoma (HCC) while the 4.2x5.4 cm mass was evaluated as a large necrotic lymph node at the porta hepatis. The liver biopsy’s findings of the 6.2x7.1 cm mass showed a high grade undifferentiated carcinoma favoring HCC and the alpha-fetoprotein was also abnormally high. The patient has undergone induction chemotherapy with cisplatin and 5-fluorouracil followed by concurrent chemoradiotherapy for the HNSCC, while the HCC is stable and remains untreated until the HNSCC is fully addressed. This report provides valuable insight of an uncommon case of HNSCC with a SPM in the liver while illustrating the systematic approach towards a diagnosis based on the results of lab studies to distinguish SPMs from metastases. These types of precise diagnoses are necessary for appropriate treatment of the patient and additional work up is necessary to identify SPMs from metastases.