Background: Bone marrow transplant (BMT) is an effective treatment for haematological malignancies. However, there are concerns about the late consequences due to the total body irradiation and high dose chemotherapy used to maintain the transplant. Patients that undergo BMT frequently develop graft versus host disease. There is a well-established increased risk of solid cancer development after a bone marrow transplant; in particular, patients are at high risk of head and neck squamous cell carcinoma. To date, there is sparse information on the long term treatment outcomes of patients diagnosed with head and neck squamous cell carcinoma (HNSCC) after a BMT. The aim of this study was to retrospectively analyze patients who developed HNSCC after receiving a BMT and developing graft versus host disease.
Materials and Methods: Retrospective chart review of patients with HNSCC and GVHD after undergoing a BMT, between Jan 1, 1968 to Jun 30, 2016. All patients received treatment at Princess Margaret cancer Centre, Toronto. REB approval was obtained before the study was commenced. Patients included were who had undergone a BMT and received a diagnosis of GVHD and OCSCC. Patients excluded: patients with Fanconi Anemia or a primary immunodeficiency. Outcomes measured include risk factors, tumor characteristics, progression free and overall survival. Kaplan Meier curves were used for estimation of progression free survival and overall survival from the first diagnosis of HNSCC.
Results: Twenty-five patients were identified, 21 (84%) male and 4 (16%) female. Fifteen (60%) patients had never smoked, 15 (60%) patients did not drink alcohol. The mean age for BMT was 41 years (18-65). The most common indication for BMT was chronic myologenous leukaemia with 9 (36%) of patients, followed by acute nonlymphoblastic leukaemia in 8 (32%) patients. The bone marrow donor was an HLA identical sibling in 11 (44%) cases. All patients developed chronic graft versus host disease, with the most common site being oral cavity (19 patients, 76%). The mean age for diagnosis of head and neck squamous cell carcinoma was 52 years (28-76). The mean time between BMT and the diagnosis of HNSCC was 12 years (2-13). The most common head and neck subsite was tongue, 13 (52%) patients. Thirteen (60%) patients presented with stage I disease, however 6 (24%) patients presented with stage IV disease. The most common management for the head and neck cancer was surgery alone, 15 (60%) patients. Eight (32 %) patients developed a subsequent second head and neck primary squamous cell carcinoma. The 2 year progression free survival (PFS) was 61.4%, 5 year PFS was 56.7%. The 2 year overall survival (OS) was 82.8%, 5 year overall survival was 68.7%.
Conclusion: This is the largest reported series of patients who developed a head and neck squamous cell carcinoma subsequent to their BMT and GVHD. The results demonstrate that these patients don’t have the classic risk factors for HNSCC. HNSCC can develop many years after the bone marrow transplant, with second HNSCC also being common. The majority of patients present with early stage disease and are treated with surgery alone.