Early outcomes of complete excision followed by immediate postoperative single fractional 10 Gy for anterior chest keloids: A preliminary results

Abstract

Treatment of chest keloids is challenging. The aim of this study is to present our experience using surgical excision followed by postoperative single fractional 10 Gy radiotherapy for recurrent anterior chest keloids on the same day. 16 patients with recurrent anterior chest keloids were treated with complete excision followed by single‐fractional 10 Gy radiotherapy within eight hours postoperatively. The mean follow‐up period was 12 months. (10–14 months) The outcome was reported with a recurrence‐free rate. We also reported side effects. The overall recurrence‐free rate was 81.25%. The side effects were minimal, with two reported hyperpigmentation which was subsided after six months, and two cases of acute wound problems. Second malignancy or serious complications were not reported. Our preliminary results show positive outcomes of complete excision followed by postoperative single fractional 10 Gy radiotherapy for recurrent anterior chest keloids on the same day. Our current study needs further long‐term validation with more diverse patients.

1. INTRODUCTION

Keloids are considered benign fibroproliferative skin tumours growing beyond the site of the original dermal injury, which causes patient discomfort both physically and psychologically. Although traditionally viewed as a form of skin scarring, keloids display many cancer‐like characteristics such as progressive uncontrolled growth, lack of spontaneous regression, and extremely high recurrence rates. ¹

Postoperative radiotherapy modalities for keloids include superficial X‐ray therapy, electron beam therapy, and brachytherapy. Such adjuvant radiotherapy significantly decreases the recurrence rate among various adjuvant treatments. ² Although many regimens have been reported effective, there is no universally accepted radiation dose and fractionation or modality to treat keloids, leaving space for further research to optimise adjuvant radiation therapy protocol. Likewise, the optimal timing of radiation therapy is still controversial.

Keloids on the anterior chest wall are very common because it possesses high skin tension. ³ , ⁴ Also, the chest's skin tissue has much less mobility than other anatomical locations. ⁵

The current study aims to share our preliminary results of complete surgical excision followed by immediate postoperative adjuvant single fractional 10 Gy radiation therapy on the same day (within eight hours after surgery) for recurrent anterior chest keloids to prevent keloid recurrence.

2. PATIENTS AND METHODS

Patients were treated with surgical excision followed by immediate postoperative radiation therapy at our hospital. The mean follow‐up period was 12 months. (range, 10–14 months) Patients with recurrent anterior chest keloids with documented previous multiple treatment failures at other hospitals who presented to the outpatient clinic were included in the study. Complete excision and postoperative radiation therapy were performed on the same day. (Between six and eight hours postoperatively) We regularly follow‐up with the patient at the one‐month interval. We analysed data including patient age, gender, multiplicity of keloids, age of keloids before treatment, anatomical locations, previous treatment history and modality, recurrence, and clinical photographs. The outcome was reported with a recurrence‐free rate (RFR). Side effects were reported in detail. A telephonic interview was taken for those patients who could not come to the hospital for regular follow‐up. The institutional review board approved the study, and all patients provided informed consent.

Inclusion Criteria (1) the keloid was elevated and extended beyond the dimensions of the initiating injury site or lesion; (2) the patients had symptoms of keloids such as pruritis, pain, or paresthesia; (3) the patients were older than 18 years; (4) the chest keloids were previously treated but ended up with non‐responses/aggravation or recurrence, and (5) the patients who had not been previously treated with radiotherapy.

Exclusion Criteria Patients were excluded from the study (1) if they were unavailable for follow‐up, and all patients who were included agreed to comply with the treatment protocol. (2) Patients were excluded from the study if they received additional adjuvant therapy other than radiotherapy during treatment. (3) if histologic confirmation was not obtained, or (4) if there was a history of intralesional steroid injection in recent three months.

3. COMPLETE EXCISION AND POSTOPERATIVE CARE

All cases were performed under local anaesthesia. We excised keloid lesions entirely without leaving any remnant keloid tissue, and bleeding was meticulously controlled by step‐by‐step monopolar coagulation. After saline irrigation, we closed wounds with appropriate approximation using vicryl 3–0, PDS 4–0, and nylon 4–0 interrupted or continuous sutures. In some cases, the wound was covered with local flap rotation, especially with a vertical height longer than 5.5 cm.

We do not insert any drains. Instead, we applied compressive wound dressing to prevent hematoma or seroma formation. All keloids were sent out for histologic examination to confirm the diagnosis. All stitches were removed on postoperative day 21.

4. ADJUVANT RADIATION THERAPY PROTOCOL

After complete surgical removal of the keloid lesions, all patients received radiotherapy within eight hours of surgery on the same day. The planned target volume included the operative scar with a margin of 1.0–1.5 cm. A Custom Cerrobend block was used to shield non‐target areas. The patients were irradiated with a 6 MeV electron beam by a linear accelerator at 100 cm source‐to‐skin distance. A 0.5–1 cm bolus was applied over the skin. A single fraction of 10 Gy was prescribed to the 93–95% isodose line for all cases. The corresponding biologically equivalent dose (BED) was calculated as 20 Gy (at α/β of 10). The BED was 60 Gy when adopting α/β of 2 based on a large meta‐analysis, which depicted keloids as late‐responding tissue.

5. FOLLOW‐UP AND OUTCOME ASSESSMENT

A follow‐up period of about 12 months was required. Treatment outcome was recorded as recurrence or non‐recurrence. Non‐recurrence was defined as a scar without signs of elevation and extension, although slight scarring or redness could be present. Recurrence was defined as any scar elevation or extension beyond the original surgical field. We also reported side effects.(Table S1).

6. RESULTS

Sixteen patients were included in the study: seven females and nine males with a median follow‐up time of n months (range, 10–14). Baseline demographics are presented in Table 1. One patient had a history of previous surgery for keloids, and all patients had been previously treated with intralesional steroid injection. The representative cases are shown in Figures 1 and 2.

TABLE 1.

Baseline patient demographics and follow‐up outcomes

#	Gender	Age	Fitzpatrick skin type	Previous treatment	cause	Chief complaint	The biggest size in the chest	Dimension (cm2)	other keloid lesions except anterior chest	Multiplicity in the chest	Any acute wound problems within 3 weeks after treatment	Secondary effects of radiation or Dermatitis radiation based on CTCAE v5.0	Recurrence
1	F	38	III	ILS	acne	throbbing pain	4 × 2.5 cm	10	Back, surgical excision followed by ILS	Y, 3 in total	Yes	Dermatitis Gr 4 (wound dehiscence, postop 6 months)	Yes
2	M	29	IV	ILS	acne	pruritus	3 × 2 cm	6	Abdomen, surgical excision followed by ILS	N	N	N	N
3	F	28	IV	ILS	sebum	pruritus	6 × 2 cm	12	Lt shoulder, Lt chin, surgical excision followed by ILS	Y, 2 in total	N	Hyperpigmentation (subsided within 6 months)	N
4	F	74	IV	ILS	CABG	pain	8 × 2 cm	16	Rt. shoulder, surgical excision alone	N	N	N	N
5	F	63	IV	ILS	Surgery	discomfort	6 × 3.5 cm	21	Both breasts, surgical excision followed by ILS	Y, 3 in total	N	N	N
6	M	68	IV	ILS+ILC	Burn	pruritus	14 × 3 cm	42	N/A	N	N	N	N
7	F	51	IV	ILS	Acne	pruritus	3 × 2 cm	6	Lt shoulder, surgical excision followed by RT	N	N	N	N
8	M	39	IV	ILS	Acne	pain	5 × 2 cm	10	N/A	N	N	N	N
9	F	24	IV	ILS	sebum	pain	5 × 2 cm	10	N/A	N	N	Hyperpigmentation (subsided within 6 months)	N
10	M	26	IV	ILS	Acne	pain	5 × 2 cm	10	N/A	N	N	N	N
11	M	32	IV	Surgery +ILS	Gynecomastia surgery and abdominoplasty	pruritus	16 × 3 cm	48	Umbilicus, surgical excision followed by ILS/ both nipple areolar complexes, NYT	Y, 5 in total	N	N	N
12	F	52	III	ILS	Acne	pruritus	6 × 2 cm	12	N/A	N	N	N	Yes
13	M	25	III	ILS	Infected epidermal cyst	pruritus	5 × 2.5 cm	12.5	N/A	Y, 2 in total	Yes	N	Yes
14	M	45	IV	ILS	Acne	throbbing pain	3 × 2 cm	6	Umbilicus, NYT/ lower abdomen, NYT	N	N	N	N
15	M	53	IV	ILS	Unknown	pruritus	4 × 2.5 cm	10	Lt. arm, Rt. knee, Rt. Posterior calf, Surgical excision with multiple z plasties.	N	N	N	N
16	M	47	IV	ILS	Acne	throbbing pain	8 × 4 cm	32	N/A	N	N	N	N

Abbreviations: CABG, Coronary artery bypass graft; CTCAE, Common Terminology Criteria for Adverse Events; ILC, Intralesional chemotherapy; ILS, intralesional steroid injection; N/A, Not applicable; NYT, not yet treated.

FIGURE 1.

(Case #3 in Table 1) (A) A 28‐year‐old patient with a 6 × 2 cm keloid size at her anterior chest came to our department with sharp pain, pruritus, and disfiguring appearance. (B) Her chest keloid was excised entirely. (C) On the same day of the surgery, a radiation oncologist at our hospital designed the area to be irradiated. (D) Postoperative appearance one year after

FIGURE 2.

(Case #5 in Table 1) (A) A 63‐year‐old patient with a 6 × 3.5 cm, a 6 × 2.5 cm, multiple 1 × 1 cm keloid at her anterior chest and breasts came to our department with pain, pruritus, and disfiguring appearance. (B) Her chest keloid was excised entirely, and local flap reconstruction ¹⁰ was performed. (C) On the same day of the surgery, a radiation oncologist at our hospital designed the area to be irradiated. (D) Postoperative appearance one year after

Three patients experienced a recurrence resulting overall RFR of 81.25%. Severe complications were not observed. There were only two hyperpigmentation and two acute wound dehiscence. Despite short follow‐up periods, second malignancy or serious complications were not reported.

7. DISCUSSIONS

In this study, complete surgical excision followed by immediate postoperative single fractional 10 Gy effectively treats recurrent anterior chest keloids. All the patients were treated with electron beam radiotherapy using a linear accelerator in our study. Lower energies of electron beams such as 4–6 MeV achieve a high dose at the required depth while sparing the critical deeper structures. Dose homogeneity is easily achieved and has a shorter treatment time.

To our knowledge, only one study by Song et al. used a single fractional 10Gy for treating keloids. ⁶ They treated 12 patients in total. (Median age was 32 years). However, only four chest keloid patients were included in that study. Their mean follow‐up periods were 20 months, and BED2 and BED10 were 60Gy and 20Gy, respectively. Their reported recurrence rate was 0%. The difference between their study and ours was radiotherapy timing. We used postoperative radiotherapy on the same day (within eight hours of surgery), while they used it within postoperative day 3.

This study does not exclude any patients from our patient cohort. We are still treating this condition (chest keloids) with a similar protocol with a slight refinement. However, for the scientific purpose of showing readers the outcome of this modality, we decide to report our early results. We included patients we followed up with for at least approximately one year. (range, 10–14 months).

Despite much literature supporting the efficacy of adjuvant radiotherapy for keloids, the optimal dose and fractionation of radiation have not yet been established. [5] In 2005, Kal et al. suggested a dose–response relationship for treating keloids in their literature review. ⁷ They calculated the BED of the various irradiation regimens using the linear‐quadratic concept, where they adopted α/β of 10 Gy assuming keloids as an acute‐reacting tissue.

Sakamoto et al. retrospectively analysed 194 keloids in 119 patients who received postoperative radiotherapy with a total dose ranging from 16 Gy in eight fractions to 40 Gy in eight fractions. ⁸ By calculating BED according to Kal et al, ⁷ they reported a similar dose–response relationship, proposing 20 Gy in five fractions with a BED value of 30 Gy (α/β = 10) as the optimal dose. ⁸

In 2011, Dr Flickinger suggested a much lower α/β ratio of 1.12–2.86 (mean 2.08) for keloids in his radiobiological modelling of pooled data of 2515 resected keloids. ⁹ The authors estimated the best fitting radiobiologic parameters, including α/β ratio, rather than assuming values. The low α/β ratio of keloids, similar to the value of late radiation injury reaction, means that hypofractionation radiotherapy with a large fraction size can be the best strategy to treat postoperative keloids. ⁹

The calculated BED of the dose used in our study, 10 Gy in a single fraction, was 20 Gy when assuming α/β = 10 and 60 Gy when assuming α/β = 2. The favourable outcomes in our study, with a RFR of 81% at one year, are in line with the results of Dr. Flickinger. This single‐fraction regimen is more convenient and cost‐saving for patients than multiple‐fraction radiotherapy.

As described in Table 1, two of three recurred cases were related to early wound healing disruptions within three weeks after initial surgical excision followed by radiation therapy. Initial wound healing retardations cause prolonged wound dressing or require further secondary healing. This series of delayed wound healing makes antecedent radiation therapy less efficacious than those without wound healing problems. Therefore, based on our current experience, strict acute wound care is one of the most critical factors leading to better outcomes in chest keloid treatment.

Also, two recurred cases (12.5%, 2/16) were female patients and Fitzpatrick skin type III. For this reason, we are attempting to further customise our radiation protocol based on gender and Fitzpatrick skin type when treating anterior chest wall keloids. We expect to report the outcome of this customised protocol in the future.

In recurrent cases despite our treatment, regardless of its causes, we first attempted to treat those with silicone gel sheeting. Then, if unsuccessful, we used an intralesional steroid injection at least two months after initial treatment. This is because steroid injection within two months tends to incur wound disruption based on our prior experience.

The adverse reactions to radiation therapy are consistent with those reported in previous studies, including hyperpigmentation, wound dehiscence, and acute radiation dermatitis. Among them, hyperpigmentation and dermatitis gradually improve without any further treatment. Dermatitis usually appears in the first few days and disappears in three–four weeks, while hyperpigmentation can last for months. In our study, hyperpigmentation was presented in two patients and disappeared within a year. We controlled all the mentioned complications with conservative management, including low potent steroid cream.

Radiation may activate melanocytes, thereby promoting the formation of melanin and hyperpigmentation. Radiation may also damage skin appendages, such as sweat glands, sebaceous glands, hair follicles, and basement membranes. These damages may lead to the thickening of the epidermis, atrophy of the sweat glands and sebaceous glands, and hyperkeratosis. These may cause skin dryness and weakness of the skin barrier.

One notable, interesting finding is that the prominent hyperpigmentation after radiation therapy consistently yields better outcomes in terms of keloid recurrence. We believe that hyperpigmentation is evidence of good responses to radiation therapy of keloids. However, this preliminary finding needs further validation.

Intralesional steroid injection is well‐known as one of the most commonly used methods for treating chest keloids; however, in our experience, combining steroid injection with complete excision followed by radiation therapy yields suboptimal outcomes such as wound dehiscence. In this regard, the simultaneous use of intralesional steroid injection and surgery plus radiation therapy should not be considered. The recent history of intralesional steroid injection in three months is also considered a relative contraindication of our current protocol at our hospital.

Some patients cannot have radiation therapy on the same day as surgical excision because of their schedules. Because of these patients' needs, we added a new radiation therapy protocol starting radiation therapy one day after surgical excision instead of completing complete excision, followed by immediate radiation therapy on the same day. We did not include these patients in this study. Whether radiation therapy is initiated on the same day or one day after the surgery does not significantly impact keloid recurrence. After gathering more follow‐up patients, we will report this comparative study result.

This study focused on anterior chest keloids, which many physicians still think are complex, challenging to treat, and easily recurred anatomical locations. ³ , ⁵ , ¹⁰ , ¹¹ , ¹² Although we could expand our results by including more patients with sites other than the chest, treatment varies depending on anatomical locations. So, we separately report our unique experience treating recurrent anterior chest keloids with documented treatment failure history.

Also, as a referral centre for this entity, we include patients who experience treatment failure despite surgical excision or intralesional steroid injections, intralesional chemotherapy drug injections, or combinations of these at other hospitals. In this case, we usually require two months of a treatment‐free period before starting treatment with our protocol.

This limitation is also the same for ethnicity. As our patients were all Asian, we cannot say that our findings are applied to other ethnic groups. For this reason, our current finding needs further validation in other keloid populations. Additionally, all recurred cases in this study were from Fitzpatrick skin type III rather than IV. This needs further validation, adding more patients to our study. As we mentioned, we are still treating this condition with a similar protocol, and we will update our current results with more patients in the future. Nevertheless, we suggest that ethnicity or Fitzpatrick skin type could affect the endpoint result of our protocol.

AUTHOR CONTRIBUTIONS

Tae Hwan Park designed, performed the research, analysed the data, and supervised the whole study as a principal investigator. Boram Ha and Sung Jae Kim contributed to the analysis and interpretation of the data and assisted in the preparation of the manuscript. Yu Jun Lee and Seongcheol Im provided excellent patient care and data analysis.

CONFLICT OF INTEREST

The authors have no conflict of interest regarding the submitted work.

ETHICS STATEMENT

The displayed study was carried out with respect of high ethical standards. All the studies have been approved, when required, by the appropriate ethics committee and have, therefore, been performed in accordance and in conformity to the World Medical Association Declaration of Helsinki (June 1964) and sub‐sequent amendments.

INFORMED CONSENT

All patients signed an informed consent for the procedures. For this type of study, formal consent is not required.

CONSENT FOR PUBLICATION

The patients gave permission for the publication of this study.

Supporting information

Table S1. Dermatitis radiation based on Common Terminology Criteria for Adverse Events (CTCAE) v5.0

Ha B, Kim SJ, Lee YJ, Im S, Park TH. Early outcomes of complete excision followed by immediate postoperative single fractional 10 Gy for anterior chest keloids: A preliminary results. Int Wound J. 2023;20(5):1418‐1425. doi: 10.1111/iwj.13996

DATA AVAILABILITY STATEMENT

All data generated or analyzed during this study are included in this published article.