The original cold cap
One of the considerations in scalp cooling is the incidence of scalp secondaries which if present may not be treated by chemotherapy. It has been suggested that if blood flow to the scalp is reduced delivery of chemotherapeutic agents is reduced increasing the likelihood of cancer cell survival.
In early stage breast cancer, the incidence of the scalp as the first site of recurrence is very low. Dean et al (1983) found only 2 patients with scalp metastases in 7800 women with breast cancer treated with mastectomy, with or without post operative adjuvant therapy, an incidence of 0.025%. Clearly, primary metastases are rare.
Does scalp cooling increase the incidence of scalp recurrence in early stage breast cancer?
The most extensive literature report on scalp cooling was conducted by Tollenaar (1994) who reviewed 25 publications (1973 – 88) with a total of 1282 patients. No case of scalp metastases was reported in scalp cooled patients receiving adjuvant chemotherapy. In their own scalp cooling study of 35 adjuvant treated breast cancer patients no case of scalp metastases was found with a mean follow up of over 4 years. More recent published studies involving scalp cooled adjuvant breast cancer patients have not reported any scalp metastases (Ron 1997, Lemanger 1997).
The review by Tollenaar reported cases of scalp metastases in five scalp cooled patients with disseminated breast cancer out of a total of 96 patients. It remains uncertain whether these lesions would have occurred in the absence of scalp hypothermia.
Overall the problem of scalp metastases is very difficult to determine either way. There is currently no clinical or scientific evidence that the incidence of scalp metastases is increased in scalp cooled patients. The condition is very rare and the patient sample required to establish the answer in a randomised study borders on the impossible.
Literature commentary: Scalp Metastases
“…a practical concern is the risk of scalp metastases. This risk appears to be minimal. Fisher studied 7800 women with breast cancer treated with mastectomy alone or with post operative adjuvant therapy. Of these patients, only 2 experienced scalp recurrence (approximately 0.025%) as their first site of recurrence. Both these patients had positive lymph nodes and one received adjuvant chemotherapy. These date clearly indicate that there is a minimal risk of scalp metastases as the site of first recurrence in breast cancer patients……..we believe that scalp hypothermia can routinely be used with a variety of solid tumours such as breast, ovarian, pancreatic, thyroid, gastric, osteosarcomas etc.”
Dean J.C. et all J Clin Oncol 1 33 (1983)
“It is concluded that the hair preserving effect of scalp cooling is mainly due to the metabolic effect of cooling, and only to a minor extent due to the flow reducing effect”
Bulow J at al Scand J Clin Lab Invest 45 505 – 508 (1985)
“None of the patients (in our study) that were treated with scalp hypothermia developed scalp metastases (mean follow up time 48 months) 5 cases of scalp metastases after scalp hypothermia of 96 patients treated for disseminated breast cancer were reported in two series. No case reports of scalp metastases after scalp cooling for adjuvant chemotherapy for breast cancer were found in the literature.”
Tollenaar RAEM et al Eur J Cancer (A) 30 1488 – 1453 (1994)
“…nor has the literature yet yielded reports of any increased incidence of scalp metastases in the women that have undergone hypothermia in the past 15 years.”
Ron IG Support Care Cancer 5 136 (1997)
“No reported scalp metastases after the cold cap in adjuvant breast cancer chemotherapy was found in the literature. In our experience, we have been using the cold cap for about 15 years and no increase in the rate of scalp metastases has been observed.
Lemanger M et al Eur J Cancer 33 297 – 300 (1997)