29 Skin Cancer

Skin Cancer

13

THE GEC ESTROHANDBOOKOF BRACHYTHERAPY | Part II Clinical Practice Version 1 - 30/04/2017

Table 31.2: Local control, cosmesis and adverse side effects after Interstitial skin brachytherapy with LDR in basal cell and squamous cell skin carcinoma: various patient cohorts with heterogene- ous treatment schedules (retrospective evaluation)

Author [reference]

Tumour localization Number

Local control

Good cosmesis

Adverse side effects

Year

Mode

Follow up

97% if primary 94% if recurrence

13% 31%

Daly [34]

1984

Eyelid

165

192 Ir

5 y

Nasal vestibule

Baris [33]

1985

22

192 Ir

2 y

96.4%

0%

13% ulcers 4% necrosis

Mazeron [36]

1986

Ear/pinna

70

192 Ir

5 y

99% <4cm: 78% >4cm: 11%

95% if primary 88% if recurrence

Mazeron GEC [32]

93% 87%

1988

Nose

1676

RT/ 192 Ir

2 y min

2%

Crook [30]

1990

Nose

468

192 Ir

5 y

97.5%

94%

2%

97% if primary 94% if recurrence

Debois [31]

1994

Nose

370

137 Cs

2y

97%

0%

Maes [37]

2001

Face

173

192 Ir

45m

95%

89%

3.6%

Gambaro [35]

2001

Eyelid

50

192 Ir

7 y

96%

92%

92.5% if radical 88% postoperativ.

Rio [38]

2005

Face

97

192 Ir

Ducassou [39]

2011

Face

147

192 Ir

5 y

87.3%

12. RESULTS

12.2 Local control rates after HDR brachytherapy HDR Brachytherapy has substituted LDR nowadays. Better surgical techniques likeMohs’ surgery [40] have been developed, and other therapeutic options, cryocoagulation, photodynamic therapy or external skin treatment with imiquimod can be considered [41]. Therefore few studies are available that report the results of high-dose rate brachytherapy with custom-made surface moulds for skin tumours. The results appear to be very favourable with 5 year actuarial local control rates of 88-98% and without severe late complications (Table 31.3). Svoboda et al. [42] used moulds made with two 0.75 cm square silicone bases and 2 mm endobronchial catheters fixed between them. In lesions close to eyes, 4 mm lead shields were used for protection. The dose was prescribed to the surface of the applicator. They treated 87 cutaneous carcinomas (BCC and SCC) obtaining in each of thema complete tumour response and very good to excellent cosmetic result, with recurrence in four cases, all them with an initial diameter greater than 2cm and a depth greater than 3mm. Allan et al. [43] described complete response in 13 patients with cutaneous carcinomas of the pinna treated by means of moulds for HDR-BT. There were no cases of Grade 4 dermatitis, the cosmetic results were excellent and they report no relapse during the 18-month follow-up.

12.1 Local control after LDR brachytherapy With doses of 60 – 65 Gy, local control is excellent for T1 – T2 skin cancers. Five-year recurrences rates range from 1 to 5% for non-melanoma skin cancers of the nose [30, 31, 32] and nasal vestibule [33], the eyelids [34, 35], ear and the pinna [36] or different areas of the face [37]. However, if the patient is treated for a recurrent tumour after previous surgical resection, the recurrence rate is higher, ranging from 6 to 13%. Most of these studies are retrospective mono-institutional cohort studies, only one is a multicentre study (Table 31.2). The more recent series, with interstitial 192-Ir LDR Brachytherapy, confirm good results: Rio et al. [38] treated 97 patients with periorificial facial skin carcinomas, and the local control rate was 92.5% for those cases treated with radical intention and 88% for those with postoperative intention. AndDucassou et al. [39] treated 147 facial carcinomas with local-regional-relapse-free survival of 96.6% at 2 years and 87.3% at 5 years, local control was better after primary treatment than after recurrence, and for basal cell carcinoma than for squamous cell carcinoma.