Chapter 165 Fibrocystic Breast Disease
General Considerations
Even the majority of densities that are unilateral are benign. If the edge of the mass merges in one or more places with the surrounding breast tissue, it is considered nondominant. It is important to evaluate these masses and make a careful distinction between a dominant mass and a mass of concern. Evaluation may include fine-needle biopsy. The majority show some nonproliferative change, and about 20% show proliferative changes without atypical hyperplasia. None of these conditions places a woman at increased risk for breast cancer. Only the 5% who show atypical hyperplasia carry a significantly increased risk of breast cancer, especially when there is family history of a first-degree relative with breast cancer.1
Therapeutic Considerations
Discussion of premenstrual syndrome (see Chapter 202) may help to further elucidate factors that can influence FBD. The factors discussed here are not covered in depth in Chapter 202 and are particularly relevant to FBD.
Dietary Considerations
Methylxanthines
Epidemiologically,2 experimentally,3–5 and clinically3–5 there is strong evidence supporting an association between methylxanthine consumption and FBD. Caffeine, theophylline, and theobromine are all known to inhibit the action of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate phosphodiesterase and to significantly elevate their levels in breast tissue.3–5 In turn, increased levels of these cyclic nucleotides excessively stimulate protein-kinase activities and cause the overproduction of cellular products such as fibrous tissue and cyst fluid.
In one study, limiting methylxanthines (coffee, tea, cola, chocolate, and caffeinated medications) in the diet resulted in improvement in 97.5% of the 45 women who completely abstained, and in 75% of the 28 who limited their consumption. Those who continued with little change in their methylxanthine consumption showed little improvement.3 According to this study, women may have varying thresholds of response to methylxanthines. However, three other studies have shown no association between methylxanthines and FBD.6–8 Stress may also play an important role because fibrocystic breasts appear to be more responsive to epinephrine, the presence of which increases adenylate cyclase activity and hence cAMP production.
Fiber
A comparison between the diets of 354 women with benign proliferative epithelial disorders of the breast and those of 354 matched controls and 189 unmatched controls found an inverse association between dietary fiber and the risk of benign proliferative epithelial disorders of the breast.9 An increased intake of dietary fiber may be associated with a reduced risk of both benign breast disease and breast cancer.
Soy
In an uncontrolled study, 64 premenopausal women consumed soy protein for 1 year. The women and their physicians reported a subjective reduction in both breast tenderness and FBD. Evaluation by breast-enhanced scintigraphy also showed that a nonstatistical reduction occurred in both the average and maximal breast tissue activity following 1 year of daily soy consumption. There was a statistically significant reduction (P < 0.01) in variability of tissue activity following 1 year of soy protein treatment.10 These results are promising and included both objective and subjective findings consistent with a reduction in FBD.
Nutritional Supplements
Evening Primrose Oil
Several studies have examined EPO for both mastalgia and breast cysts. In one randomized controlled double-blind trial, 120 women were assigned to receive one of four treatments: (1) fish oil and control oil; (2) EPO and control oil; (3) fish oil and EPO; or (4) both controls.11 Corn oil and corn oil with wheat germ oil were the control oils. The decrease in the number of days with pain was not significantly different between the groups. Pye et al, combined results from randomized trials and open studies that included 291 women with cyclic and noncyclic breast pain. Their report indicated a 45% response rate to EPO for cyclic mastalgia compared with 19% response rate in placebo groups. They also reported a 27% response rate to EPO in women with noncyclic mastalgia compared with a placebo response rate of 9%. Unfortunately, this publication did not provide sufficient information as to the details on the quality of the studies.12 In another study, 73 women with breast pain randomly received 3 g/day of EPO or placebo. After 3 months, pain and tenderness were significantly reduced in both the women with cyclic breast pain and those with noncyclic pain. The women who took the placebo experienced no significant improvement.13 A randomized trial of 36 women with severe cyclic or noncyclic mastalgia were randomly given 320 mg of gamma-linolenic acid/day from EPO or placebo for 4 months. After 4 months, no consistent clinical improvements were observed.14
One randomized controlled trial examined the effectiveness of EPO for recurrent breast cysts.15 There was a slight but statistically significant reduction of breast cyst recurrence in women receiving EPO. Two hundred women with breast cysts were randomly assigned either six capsules per day of EPO or placebo for one year. Although there were fewer cysts in the EPO group (92 vs 113), this difference was not statistically significant.