Apart from the climacteric symptoms, increased cardiovascular disease, cerebrovascular and musculoskeletal deterioration are taken into consideration. Women with an early menopause have a higher incidence of ischemic heart disease and overall mortality risk is reduced with HRT in observational studies [53–55]. Unfortunately, there is little information that allows the clinician to determine the least disadvantageous HRT combination. There is an ongoing research to establish the impact of body identical hormones (particularly the progesterone component) compared to synthetic hormones, suggesting a reduced metabolic impact of estradiol, and natural progesterone compared to synthetic progestogen, in addition to possible reduced breast cancer risk [56]. It seems logical to replace women’s hormones with identical compositions, if possible. Younger women with cervical cancer may wish to have replacement in the form of the combined oral contraceptive pill, although this may have a more disadvantageous metabolic impact. Those who have been hysterectomised do not require progestogen or progesterone to protect the endometrium from oestrogen stimulation, thus conferring no additional breast cancer risk. There is also no additional risk with combined HRT used before the average age of menopause, (approximately age 51). There are practitioners withdrawing progesterone opposition in systemic HRT regimens for women who have had pelvic radiotherapy with an intact uterus; but there is no published evidence to support the safety of this regimen, even though the endometrium is likely to have been ablated in most.

Table 11.2 details HRT that can be administered to those without hormone-sensitive cancers, or who are judged to have minimal risk of recurrence and a significant beneficial impact of oestrogen deficiency on their quality of life. Different routes of administration will have varying metabolic pathways with different risks and benefits. Transdermal oestrogen products in the form of patch or gel have less impact on coagulation, and therefore lower the risk of thrombosis (although the overall risk is low in younger women being treated for iatrogenic menopause compared to older naturally menopausal women). However, pelvic cancer itself confers an increased risk of venous thrombosis. Progestogen can be administered orally or transdermally in a combined patch or using an intrauterine device. Progesterone is available on oral, vaginal or rectal preparations. Androgenic properties of some progestogens may counteract the beneficial effect of estradiol on lipoproteins and increase insulin resistance [57, 58].

Although not specifically studied in a treatment group with gynaecological cancer, continuous combined or non-bleeding HRT is safer for the endometrium long-term (i.e. daily dosing of progesterone or progestogen). There may be difficulties in assessing postmenopausal bleeding in this group of women after radiation therapy due to other causes including vaginal and/or cervical stenosis, and changes in the appearance of the endometrium on imaging. Sampling the endometrium may also be difficult in this group.

Topical estrogens are an alternative for promoting vaginal health, with a significant reduction in recurrent cystitis or urinary tract infection that can be provoked by intercourse or dilator use in addition to improvement in vaginal symptoms of itching, burning and irritation, secondary to vaginal atrophy. These agents are safe even in those with hormone sensitive cancers in the vast majority of patients. Vaginal tablets, pessaries, creams and a ring are available for use. These could potentially be used indefinitely for those who are symptomatic and not using systemic HRT. They may also reduce bleeding with dilator use and intercourse. Topical estrogens are minimally absorbed during the first 2 weeks of daily use only. After this, levels are generally consistently below the normal postmenopausal levels.

Consideration of androgen deficiency should also be undertaken, particularly in younger surgically menopausal women. There is data to suggest benefits for women’s sexual satisfaction, well-being, energy levels and musculoskeletal strength, although this is a controversial area in hormone replacement [59, 60]. Tibolone is a gonadomimetic alternative to combined hormone replacement with estrogenic, progestogenic and androgenic effects, and proven benefits for tissues, vasomotor symptoms and sexual functioning [61, 62].

The current recommendations regarding hormone replacement in women with induced menopause after cancer, is to administer HRT until at least the average age of natural menopause, i.e. 51 years. This approach should be assessed on a regular basis in line with current evidence. Alternatives can be considered but oestrogen with or without progestgen/progesterone is the only treatment for all consequences of oestrogen deficiency. Many herbal therapies, such as phytoestrogens, work via pathways that are not clarified, and may have hormone-like effects and therefore exhibit similar risks. Venlafaxine and gabapentin may reduce vasomotor symptoms but cause significant side effects for some [63]. Bisphosphonates can be used for prevention and treatment of osteoporosis, but long-term use is associated with fragility fractures. All these women should be counselled with respect to maintaining their cardiovascular and bone health by weight-bearing exercise, sufficient calcium and vitamin D and good diet with screening for bone density and cardiovascular risk factors as required.