Microcystic adnexal carcinoma of the head and neck: Characteristics, treatment, and survival statistics.

Studies on microcystic adnexal carcinoma (MAC) survival rates have been limited. This effort examines the association of patient demographics, treatment modalities, and tumor stage with overall survival (OS) in patients with MAC of the head and neck. All cases of MAC with primary sites of the skin of the head and neck, confirmed histologically, and diagnosed from 2004 to 2016 in the National Cancer Database, were analyzed. We utilized Kaplan-Meier and Cox proportional-hazard models to analyze the characteristics and survival outcomes of the 415 cases that met the criteria. The mean age of diagnosis was 63.8 years (SD ±15.8). Mean OS was 10.8 years with 5- and 10-year OS being 81.0% and 68.0%, respectively. Women were more frequently affected (59.0%; P < .001). Stand-alone primary site surgery was the most common treatment (81.4%): 15.9% of patients were treated with postexcision radiation therapy (RT). 18.3% were treated with RT with or without surgery and/or chemotherapy. RT was independently associated with a decreased hazard of death (HR = 0.23; P = .044). MAC of the head and neck disproportionately affects whites, is more common in women, and has the potential to metastasize. Surgical excision is the commonest treatment; our study shows benefit from judicious RT.

Analysis of Characteristics and Survival of Primary Cutaneous Adenoid Cystic Carcinoma of the Head and Neck.

BACKGROUND/OBJECTIVES: Primary cutaneous adenoid cystic carcinoma (PCACC) is a rare skin tumor. The head and neck (H&N) is the most common anatomical location. Due to limited published cases, its clinical course and management are not well understood. METHODS: The National Cancer Database (NCDB) was queried for all cases of H&N PCACC diagnosed from 2004 to 2016. Kaplan-Meier (KM) and Cox proportional hazards models were used to determine clinicopathological and treatment factors associated with survival outcomes. RESULTS: A total of 201 cases were analyzed. The average age of diagnosis was 57.7 years (± SD 15.8). There was a female predilection (57.7%; P < .05) with the most common primary site being the ear (58.2%). The average tumor size was 15.9 mm in diameter. The most common treatment was surgery alone (51.7%) with wide local excision being the common surgery performed (36.3%). 5-year and 10-year OS were 87.0% and 76.0%, respectively. A total of 65.8% of cases were localized (Stage I and II). KM analysis indicated that gender, age, insurance status, Charlson-Deyo Comobordity Score, and stage were significant predictors of OS (P < .05). Cox proportional hazards analysis revealed that patients with both private (HR 0.11, 95%CI [0.019-0.670]; P = .02) and government (HR 0.12, 95%CI [0.019-0.972]; P = .03) health insurance had a significantly decreased hazard of death than patients who were uninsured. Increasing age was associated with an increased hazard of death (HR 1.06, 95%CI [1.016-1.110]; P = .01). CONCLUSION: This study represents the largest cohort of H&N PCACC studied to date and provides important clinicopathologic information for this rare tumor. Additionally, our results emphasize the importance of health insurance as an independent predictor of survival in PCACC.