ACINIC CELL CARCINOMA

NEW YORK (Reuters Health) Oct 02 - A new study suggests some patients with acinic cell carcinoma may benefit from more-intensive therapy and longer follow-up.

"The majority of patients with these uncommon tumors of the salivary glands have a very good prognosis, and this has guided the treatment philosophy for this disease," said Dr. Michael E. Kupferman from the University of Texas MD Anderson Cancer Center in Houston.

"However, there is a segment of patients in whom there is a higher risk of recurrent disease, and intensive monitoring should be utilized in this group of patients," he told Reuters Health by email. "Additionally, the typical pattern of cancer monitoring of only 5 years is not sufficient for this disease, since these recurrences can happen 10-15 years after successful initial treatment."

Acinic cell carcinoma accounts for 3% to 9% of salivary gland neoplasms, which represent only 0.3% of malignant neoplasms.

Dr. Kupferman and colleagues sought to identify clinicopathologic factors associated with adverse survival and to assess the effect of local, regional, and distant recurrences on survival in a retrospective study of 155 patients with acinic cell carcinoma.

Overall and disease-free survival rates were significantly lower in patients older than 45 years than in their younger counterparts, partly due to a higher incidence of distant metastases seen in the older population.

Acinic cell carcinoma is more common among women than men, but the former had better overall and disease-related survival independent of stage, the researchers reported online September 26 in JAMA Otolaryngology -- Head & Neck Surgery.

Disease-free survival and disease-related survival were worse in patients who developed a recurrence, and cervical lymphadenopathy was associated with increased disease-related mortality.

Patients with stage I and II disease had significantly better overall and disease-free survival (compared with patients with higher stages), whereas patients with tumors larger than 3 cm had significantly worse survival (compared with patients with smaller tumors).

The extent of surgery, the presence of positive surgical margins, and the addition of post-operative radiation did not affect survival.

Multimodality therapy achieved local control rates of 80%, but one in five patients developed a recurrence. Prior recurrence predicted subsequent recurrences, and distant recurrences were associated with both prior recurrence and age older than 45 years.

Most of the 13 deaths (8.4%) were due to the development of distant metastases. The mean time from disease to death was 3.8 years.

"There is a subset of patients, including those with large tumors and patients over the age of 45, whose prognosis is less favorable. These patients need intensive treatment for their local disease, and continued lifetime surveillance to monitor for recurrences," Dr. Kupferman said.

"Currently, there are very limited chemotherapeutic options for metastatic disease," he noted. "When tumors recur locally, surgery and radiation are recommended. With increased understanding of the molecular changes that occur within these cancers, we can identify novel targeted agents that may be used to treat metastatic disease."

Dr. Kupferman added, "Due to the rarity of this cancer, patients with acinic cell carcinoma should receive treatment at high-volume centers with the necessary expertise in all aspects of cancer care, including surgery, radiation and chemotherapy. Patients who have recurrences have a less favorable outcome, and thus optimizing the initial treatment is paramount."

SOURCE: http://bit.ly/15HaZ7v

JAMA Otolaryngol Head Neck Surg 2013.