An efficient statistical algorithm for a temporal scan statistic applied to vaccine safety analyses.

In the US, the Vaccine Safety Datalink (VSD) project, sponsored by the Centers for Disease Control and Prevention, conducts near-real-time, population-based, active surveillance for vaccine safety. One of the steps in analyzing signals, if there are enough cases, is to apply temporal scan statistics. The purpose is to determine if the cases clustered in time within an overall a priori defined post-vaccination observation interval. We presented a relatively efficient and accurate algorithm for the purely temporal scan statistic as applied to vaccine safety investigations. It only needs SAS/BASE(®) software, and the algorithm is simple enough to be programmed in another software languages. Our present work is focused on incorporating the temporal scan statistic algorithm within our previous approach for finding an optimal risk window for studies of vaccine safety.

Pilomatrixoma of the parotid in a one year old girl (calcifying epithelioma of Malherbe).

Pilomatrixoma is a rare tumor occurring in fewer than 1:1000 skin biopsies. Its presentation as a solitary parotid mass treated by wide excision is unusual, with only three previously reported cases in the world's literature.

Verrucous carcinoma--changing concepts in management.

Verrucous carcinoma is an unusual, non-metastasizing, distinct variant of a well differentiated squamous cell carcinoma. Multiple biopsies are frequently necessary to establish its diagnosis. Seven of 10 patients treated with irradiation showed no evidence of anaplastic transformation. A high recurrence rate in tumors of the oral cavity treated with either irradiation or surgery alone is noted. Extensive lesions in this area may benefit from combined therapy. A good response to radiotherapy with a low recurrence rate in small laryngeal lesions is recognized. Irradiation should be considered in the management of this tumor without undue concern for change in its biologic behavior.