To determine the risk of Kaposi's sarcoma in persons 

with HIV infection, we followed a group of 1600 

HIV seropositive men without a prior history of 

sarcoma for 8 years with annual dermatologic exami- 

nations.

To assess the benefits of sigmoidoscopy, we assessed 

the prior history of sigmoidoscopy in 352 adults with 

biopsy-confirmed colon cancer and in 704 individuals 

without cancer, all of whom were enrolled in our HMO 

from 1990 to 1995.

To determine the relationship of cigarette smoking to 

renal dysfunction, recent smoking was assessed using 

serum cotinine levels, and GFR was measured by 

iothalamate clearance. Our main finding was that the 

mean GFR was significantly lower in smokers than in 

nonsmokers.

To estimate the benefits of catheter ablation for SVT, 

we compiled the results of 17 patients with refractory 

SVT who underwent catheter ablation at our hospital in 

1997.

An 18-year-old woman has noticed worsening acne on 

her face. She is disturbed because she is starting college 

in the fall and does not want to look like the "pimple- 

faced kid" she has been in high school. She has tried 

over-the-counter topical benzoyl peroxide intermit- 

tently with mild improvement. Her examination 

reveals scattered comedones without evidence of cysts, 

papules, or other signs of inflammation. Which of the 

following statements is correct?