Case Presentation: A 53 year old man with a history of stage III squamous cell carcinoma (SCC) of the esophagus (pT3N3) was admitted for dysphagia and found to have a mandibular mass and a painful finger nodule. The patient initially presented to an outside hospital four months prior with dysphagia and weight loss. He was found to have an esophageal mass on endoscopy, with biopsy showing SCC. Chest CT showed precarinal, subcarinal, and gastroesophageal lymphadenopathy. The patient underwent esophagectomy without preoperative chemoradiation and pathology confirmed moderately differentiated invasive SCC with 6/12 lymph nodes positive for metastatic SCC. Adjuvant radiation had been delayed due to insurance issues and loss to follow up. A PET scan one month prior showed a right paratracheal mass and locoregional lymph nodes concerning for recurrent disease, but no distant metastatic disease. Seven days prior to admission, the patient noticed an erythematous nodule on his index finger. He completed seven days of antibiotics for presumed skin infection with no improvement in symptoms. At the same time, he also noted a small mass below his left premolar. On admission, physical exam was notable for a tender, erythematous, necrotic-appearing 1cm nodule above the nail bed of the distal phalanx of the 2nd digit of the left hand, and a 2cm painful, immobile mass in the buccal mucosa below the left mandible. A bone scan demonstrated focal increased uptake only in the left 2nd digit distal phalanx. Neck CT confirmed a superficial soft tissue mass along the buccal surface of the left mandibular body with extension into the dermis but no bony erosion. Punch biopsy of both lesions revealed invasive high grade SCC. Further work up with CT of the chest/abdomen/pelvis showed a paratracheal mass and regional lymphadenopathy, consistent with prior PET scan, with no evidence of distant metastases. The patient underwent palliative amputation of the distal phalanx, excision of the left mandibular gingiva, and was subsequently started on chemotherapy for recurrent metastatic esophageal cancer. 

Discussion: This is only the second reported case in the literature of esophageal SCC with metastases to the phalanx and gingiva.  Esophageal carcinoma typically metastasizes to the liver, lungs, bone, or adrenal glands. SCC metastases are usually intra-thoracic. Metastases to the buccal mucosa and gingiva are very rare, representing only 1% of oral cavity malignancies and often arise from lung, kidney, skin, or breast cancers. Chronic inflammation from gingivitis or periodontitis is hypothesized to play a role in attracting metastatic cells. The most common primary tumors with metastases to the bone are lung, kidney, and breast. Metastases to the hand are exceedingly rare since there is less red marrow, and comprise only 0.1% of bony metastases. Repetitive trauma is hypothesized to increase blood flow to the area and metastases to the phalanges are often observed in the dominant hand. 

Conclusions: Although rare, oral cavity and hand lesions should be considered as possible sites of metastases. These lesions are often misdiagnosed as infections or unrelated processes, but they may represent distant metastatic cancer and require further workup.