On the basis of data from a large population of women 30 to 64 years of age who had had three or more consecutive negative Papanicolaou smears, the authors conclude that, as compared with annual screening for three years, screening performed once every three years is associated with an excess risk of cervical cancer of no more than 3 in 100,000.

These data support recent recommendations that the interval between cervical-cancer screenings be extended to as long as three years among women 30 years of age or older with previous negative cytologic tests.

This study identified 300 patients in Israel and 2822 in the United States who presented with clinical malaria after travel to areas of endemic disease. Of these patients, 36 percent presented more than two months after returning home, and most had used an antimalarial regimen according to national guidelines.

Most of the agents prescribed to travelers for the prevention of malaria act on the parasite's blood stage. A different strategy and perhaps new agents will be required to prevent late-onset cases of malaria, most of which are due to Plasmodium vivax.

Germ-line mutations in the rearranged during transfection (RET) proto-oncogene are associated with thyroid cancer. These investigators studied presymptomatic patients 20 years of age or younger who had known RET mutations and had undergone prophylactic thyroidectomy. A significant age-related progression from C-cell hyperplasia to medullary thyroid carcinoma and to nodal metastasis was found in subgroups with certain mutations.

These data provide initial guidelines for the timing of prophylactic thyroidectomy in asymptomatic carriers of mutations of the RET gene.

In 130 military personnel, systemic lupus erythematosus (SLE) developed after blood samples had been stored in the U.S. Department of Defense Serum Repository. On testing, 88 percent of the 130 subjects were found to have had one or more lupus-associated autoantibodies before the clinical diagnosis. The antibodies that developed first were antinuclear, antiphospholipid, anti-Ro, and anti-La antibodies, which appeared, on average, more than three years before the diagnosis. Anti–double-stranded DNA antibodies were present two years before the diagnosis. Anti-Sm and anti–nuclear ribonucleoprotein antibodies, which developed last, were present about one year before diagnosis.

This detailed description of autoantibody development provides interesting information about the biology of systemic lupus erythematosus.

Primary progressive aphasia is an atypical dementia in which language abilities deteriorate while memory is relatively preserved. For many years, the principal signs and symptoms may be confined to the area of language. Patients may come to medical attention because of the onset of word-finding difficulties, abnormal speech patterns, or prominent errors in spelling. Neuropsychological testing can help establish the correct diagnosis.

Paraneoplastic neurologic syndromes are incited by a tumor outside the nervous system that produces a characteristic antigen of the nervous system. An immune response against the ectopic tumor antigen not only damages nerve tissue but also inhibits growth of the tumor.

An important point made in this concise review is that paraneoplastic neurologic syndromes present diagnostic challenges because the inciting tumor is often occult.