Small Lymphocytic Lymphoma Obscuring Microscopic Tonsillar Squamous Cell Carcinoma: an Unknown Occurrence with a Known Primary

Abstract

Head and neck squamous cell carcinoma (HNSCC) often presents with cervical lymph node metastases and at times the primary tumor cannot be identified despite extensive workup. Lymphoma is the second most common neoplasm in the head and neck region but is seldom synchronous with HNSCC and rarely involves regional mucosal sites. We report herein a rare occurrence of tonsillar involvement by small lymphocytic lymphoma (SLL) incidentally detected during the workup for a cervical lymph node SCC metastasis of a 52-year-old nonsmoker male. The microscopic human papillomaviruspositive SCC involving the tonsillar surface and crypts was obscured by SLL leading to the initial designation of 'unknown primary'. The occult HNSCC are likely explained by small tumor size, quality and quantity of sampling, thoroughness of endoscopic, radiological and pathological assessment or a combination of the above. The coexistence of another tumor such as lymphoma has not yet been reported as a confounding factor in the workup for cervical SCC metastasis. Since oropharyngeal SCC can be very small and Waldeyer's ring is a common site for lymphoma involvement, identification of such rare collision tumors requires pathologists' awareness, extensive sampling and occasionally ancillary studies for the accurate diagnosis and staging essential for the correct management.

Synchronous primary cancers of the head and neck region and upper aero digestive tract: Defining high-risk patients

“…Synchronous squamous cell carcinoma in the head and neck region and malignant lymphoma is rare and few have been reported. [24][25][26][27] In our retrospective analysis, 0.04% patients of all malignancies in the head and neck region had synchronous malignant lymphoma. Clinical suspicion of enlarged lymph nodes of the neck is crucial in the differentiation and diagnosis of lymphoma with that of a secondary neck node, so the awareness of this association is crucial for the correct management of this small group of patients.…”

Synchronous or collision solid neoplasms and lymphomas: A systematic review of 308 case reports

“…[39,43,86,90,95,112,130,165,221,242] A remarkable finding summarized in the present review was the cases with the presence of solid tumor metastasis in lymph nodes with lymphomas. A total of 29 cases were seen [12][13][14]40,61,[70][71][72]78,84,92,102,114,115,154,159,191,197,207,208,226,233] (Table 3). In 21 cases, the tumor metastases were observed in the regional lymph nodes, and these cases were mainly low-grade B-cell lymphoma.…”

Concurrent Squamous Cell Carcinoma and Chronic Lymphocytic Leukemia Presenting as an Enlarging Neck Mass

“…11 Though there is a case in the literature of a 52-year-old nonsmoker male who was diagnosed with small lymphocytic lymphoma during workup for an human papillomavirus–positive SCC of tonsillar primary. 12 Alcohol consumption has not reliably been shown to have positive or negative association with CLL. 13,14…”