Clinical results of soft tissue reconstruction using arterialized venous free flap after resection of soft tissue tumor in the hand

Abstract

In patients with hand tumors, advances in medicine have led to a preference for limb-sparing surgery that offers functional and aesthetic advantages. However, limb-sparing surgery often results in soft tissue defects after tumor resection. We present our clinical results using arterialized venous free flaps to reconstruct defects after soft tissue tumor resection. Four patients who underwent arterialized venous free flap for hand reconstruction after soft tissue tumor resection between June 2016 and July 2020 were retrospectively reviewed. Pathological causes of soft tissue tumors were malignant melanoma, synovial sarcoma, malignant giant cell tumor, and recurrent epidermoid cyst. Tumor locations included the palm of the hand in 2 cases, the dorsum of the hand in 1 case, and the right long finger (RLF) in 1 case. Donor sites included the distal volar aspect of the ipsilateral forearm was the donor site in 3 cases and the contralateral forearm was the donor site in 1 case. Pure venous skin flaps were used in 3 cases. Only one case used a composite tendocutaneous flap. Flaps survived well in all the patients. The mean follow-up period of the flaps was 41.75 ± 9.09 months. Recurrence or metastasis was not found, except in 1 case. Kaplan–Meier survival analysis was performed. Restricted mean survival time of metastasis/recurrence was 57.00 ± 12.99 months. The color and texture of the flap were satisfactory in all the patients. Donor-site complications were not observed in any patient. Thus, an arterialized venous free flap is considered a valuable reconstruction option after soft tissue tumor resection.

1. Introduction

Over the past few decades, advancements in the diagnosis and treatment of malignant tumors in the upper extremities have led to a preference for limb-sparing surgeries that offer functional and aesthetic advantages over amputation.^[1,2] However, even with a limb-sparing surgery, tumor resection often results in soft tissue defects, including tendon or joint exposure. As a result, reconstructing these defects has become a crucial area of focus using various methods ranging from skin grafts to free flaps.^[1]

Initially, soft tissue reconstruction was performed using local or distant flaps, followed by the introduction of free flaps using various vascular pedicles.^[1–8] However, conventional flap techniques are limited by various factors such as size, orientation, location, pedicle length, injured structure, and flap thickness. Arterialized venous free flaps offer numerous advantages over conventional flaps, particularly for hand injuries, including preventing finger stiffness, providing aesthetically pleasing results, and enabling primary reconstruction without excessive dissection of recipient and donor vessels. Therefore, arterialized venous free flaps have been used by various authors for post-traumatic hand reconstruction.^[9–13] However, because of their unique hemodynamics, which are different from those of conventional free flaps, these flaps are not always the first choice for reconstruction despite their advantages for hand reconstruction. There have been very limited reports on the use of arterialized venous free flaps for hand reconstruction following tumor excision until nowadays.^[14–16] Given that the vascularity of soft tissue defect sites following tumor excision is generally better than that after traumatic hand reconstruction, we believe that the likelihood of failure of arterialized venous free flaps is lower considering their hemodynamic characteristics. This study aimed to present our clinical results using arterialized venous free flaps to reconstruct defects following soft tissue tumor excision.

2. Materials and methods

2.1. Patients

Clinical data of 4 patients who underwent arterialized venous free flap for hand reconstruction after tumor resection with a follow-up of at least 1 year from June 2016 to July 2020 were retrospectively analyzed. Demographic data, including age, sex, primary tumor pathology, and tumor location, were obtained. These 4 patients included 2 men and 2 women. Their mean age was 55.7 years (range, 54–64 years). Pathological causes of soft tissue tumors included malignant melanoma, synovial sarcoma, malignant giant cell tumor (GCT), and recurrent epidermoid cysts. Tumor locations included the palm of the hand in 2 cases, the dorsum of the hand in 1 case, and the right long finger (RLF) in 1 case (Table 1). The arterialized venous free flap surgery was performed using the same method as described previously.^[13]

Table 1.

Demographics and characteristics of flap in patients.

Patient No.	Sex/age	Pathology of tumor*	Location of tumor	Defect size (cm2)	Reconstruction type	Flap vessel† (afferent/efferent)	Donor site/coverage‡
1	M/54	Malignant melanoma	Right palm	7 × 7	Cutaneous	1A, 2V	Contralateral distal forearm/ STSG
2	F/51	Synovial sarcoma	Right dorsum	7 × 3.5	Cutaneous	1A, 2V	Ipsilateral distal forearm/ FTSG
3	F/64	Malignant GCT	Right long finger	4.5 × 2	Tendocutaneous	1A, 3V	Ipsilateral distal forearm/ FTSG
4	M/54	Recurred dermoid cyst	Right palm	4 × 3	Cutaneous	1A, 1V	Ipsilateral distal forearm/ FTSG

^* GCT, giant cell tumor.

^† A, afferent; V, efferent.

^‡ STSG, split-thickness skin graft; FTSG, full-thickness skin graft.

2.2. Postoperative management

The authors followed the postoperative care plan described previously.^[13] The postoperative flap site was immobilized for 7 days. Capillary refilling, surface temperature, color, and bulla formation in the flap were monitored. Anticoagulation therapy was administered intravenously for 1 week. It was then changed to oral medication for another 2 weeks after surgery for all patients. If necessary, adjuvant chemotherapy was planned in consultation with the oncologist. In our case, adjuvant chemotherapy was indicated for a patient with malignant melanoma. However, he rejected it.

Regular follow-up with inspection and palpation was performed for all patients. Radiologic tests, including ultrasonography, magnetic resonance imaging, and high-resolution computed tomography, were performed to identify recurrence or metastasis in 3 patients who were diagnosed with malignancy based on biopsy.

2.3. Clinical evaluation

Flap-related factors were also assessed. Flap size was measured and classified according to Woo classification.^[11] The origin of the donor site, coverage method of the donor site, vascularity of the recipient site, number of afferent and efferent vessels, and characteristics of the flap (cutaneous or compound flap) were also obtained. The postoperative follow-up period, existence of recurrence or metastasis, donor site complications, and postoperative range of motion (ROM) of the hands and fingers were determined for all patients.

2.4. Statistical analysis

Kaplan–Meier survival analysis was performed for tumor metastasis/recurrence data of patients using JASP version 0.19.0 (JASP Team, 2024, Amsterdam, Netherlands).^[17,18]

3. Results

Flaps survived well in all the patients. Average flap size was 23.63 ± 15.76 cm² (range, 4.5 × 2 to 7 × 7 cm²). One of the flaps was small (< 10 cm²). Two flaps were medium (between 10 cm² and 25 cm²). One of the flaps was large (> 25 cm²). The ipsilateral distal forearm was used as the donor site for the flap in 3 cases, and the contralateral distal forearm was used as the donor site in 1 case. The donor site of the flap was covered using a full-thickness skin graft (FTSG) in 3 cases and a split-thickness skin graft (STSG) in one case. The vascularity of the recipient bed was good in all cases. One afferent vessel was anastomosed in all 4 cases. One efferent vein was anastomosed in 1 case. Two efferent veins were anastomosed in 2 cases and 3 efferent veins were anastomosed in 1 case. Three patients received pure venous skin flaps. Only one case had a composite tendocutaneous flap (Table 1).

Mean follow-up period of flaps was 41.75 ± 9.09 months (range, 24–72 months) (Table 2). In 3 cases, metastasis or recurrence was not observed until the last follow-up. In the case of malignant melanoma, metastasis was observed at 12 months after surgery. Kaplan–Meier survival analysis was performed to estimate the metastasis or recurrence-free survival periods. The restricted mean survival time of metastasis/recurrence was 57.00 ± 12.99 months (range, 12–72 months) (Tables 2 and 3). Color and texture of the flap were satisfactory in all the patients. Donor-site complications were not observed in any patients. Postoperative ROM of metacarpophalangeal (MP), proximal interphalangeal (PIP), and distal interphalangeal (DIP) joints of the fingers in 3 patients (2 in the palm and 1 in the dorsum of the hand) showed no limitation. In the patient with RLF GCT, the ROM was 0° to 90° for the MP joint and −30° to 90° for the PIP joint. No extension lag was observed in the DIP joint (Table 2).

Table 2.

Post-operative clinical results of patients.

Patient No.	Flap survival	Follow-up (mo)	Metastasis/recurrence*	Time to metastasis/recurrence (mo)	Range of motion in flap site†
1	Complete	33	±	12/−	MP: 90, PIP: 100, DIP: 90 (2, 3, 4, 5 fingers)
2	Complete	72	−/−	−/−	MP: 90, PIP: 100, DIP: 90 (2, 3, 4, 5 fingers). Wrist extension 45, flexion 50
3	Complete	38	−/−	−/−	MP: 90, PIP: 100 (Right long finger)
4	Complete	24	−/−	−/−	MP: 90, PIP: 100, DIP: 90 (2, 3, 4, 5 fingers)

^* +: existence of metastasis or recurrence of tumor; −: absence of metastasis or recurrence of tumor.

^† DIP = distal interphalangeal, MP = metacarpophalangeal; PIP = proximal interphalangeal.

Table 3.

Results of Kaplan–Meier survival analysis for metastasis/recurrence in patients. ^[17,18]

	Total	Events	Restricted Mean survival time (mo)	Standard error	95% CI*
					Lower	Upper
Metastasis/recurrence	4	1	57.000	12.990	31.539	82.400

^* CI = confidence interval.

3.1. Case 1

A 54-year-old male patient presented with malignant melanoma on the volar aspect of the right hand. Following wide marginal resection by a tumor surgeon, pedicle dissection was performed to reconstruct the defect. The superficial palmar arch was harvested from the volar aspect and 2 dorsal veins were obtained from the dorsal aspect. K-wire fixation was performed between the 2nd, 3rd, 4th, and 5th digits to maintain interdigital spaces. A 7 × 7 cm² venous skin flap was elevated from the distal portion of the contralateral forearm. The flap included 1 afferent vein and 3 efferent veins. However, only 2 efferent veins were used. One afferent vessel was anastomosed end-to-end to the superficial palmar arch and 2 efferent vessels were anastomosed end-to-end to the dorsal veins. The donor site was covered by STSG. At a 33-month follow-up, the flap thickness and texture were well-matched with those of the hand. There was no limitation in the finger joint ROM. However, the patient reported a slight decrease in sensation with a tingling feeling in the right 3rd finger. Grip strength was measured at 26 kg, which was 87% of the grip strength (30 kg) of the contralateral side. Pinch strength was 3 kg, which was 60% of the pinch strength (4.6 kg) of the contralateral side. The patient, who enjoys fishing as a hobby, stated that there was no discomfort in using his hands. No specific complications were observed at the donor sites. However, at the 12-month follow-up, metastases were observed in the ipsilateral proximal forearm. Thus, additional resection was performed by the tumor surgeon. Chemotherapy was declined by the patient (Fig. 1).

Figure 1.

A 54-yr-old man with malignant melanoma on the palm of his right hand. (A) Preoperative view of the right hand showing malignant melanoma on the volar side of the 3rd metacarpal area in the hand. (B) Intraoperative view after wide resection showing soft tissue defects of the 2nd, 3rd, and 4th web space and a superficial palmar arch secured in a recipient site. (C) Dissected venous skin flap of about 7 × 7 cm² including 1 afferent vein and 3 efferent veins (only 2 of them were used) from the volar aspect of the contralateral distal forearm. (D) Postoperative view after arterialized venous flap surgery showing good contour and circulation of flap. (E) Postoperative view of the contralateral donor site covered with split-thickness skin graft. (F) to (H) Postoperative view of the donor site and the recipient site at 33 mo later, showing that the flap site coordinated with surrounded soft tissue and donor site without complications.

3.2. Case 2

A 51-year-old female presented with synovial sarcoma on the dorsum of her right hand. Following wide marginal resection by a tumor surgeon, the 3rd common digital artery and 2 dorsal veins were harvested for reconstruction. A 7 × 3.5 cm² sized venous skin flap was elevated from the distal portion of the ipsilateral forearm. The flap included 1 afferent vein and 2 efferent veins. One afferent vessel was anastomosed end-to-end to the 3rd common digital artery and 2 efferent vessels were anastomosed end-to-end to the dorsal veins. The donor site was closed primarily using FTSG. At a 72-month follow-up, the flap thickness and texture were well-matched with those of the hand. There was no limitation in her finger joint ROM. Grip strength was measured at 14 kg, which was 70% of the grip strength (20 kg) of the contralateral side. Pinch strength was 2.5 kg, which was 50% of the pinch strength (5 kg) of the contralateral side. ROM of the wrist showed 45 degrees of extension and 50 degrees of flexion. The patient complained of pain in the finger joints, which was assessed to be due to degenerative arthritis. No evidence of recurrence or metastasis was found. No complications occurred at the donor site (Fig. 2).

Figure 2.

A 51-yr-old woman with synovial sarcoma on the dorsum of her right hand. (A) Preoperative view of the right hand showing synovial sarcoma on the dorsal side of the midcarpal area in the hand. (B) Intraoperative view after wide resection showing soft tissue defect of dorsum of the right hand with exposure of extensor tendons. (C) Dissected venous skin flap of about 7 × 3.5 cm² including 1 afferent vein and 2 efferent veins from the volar aspect of the ipsilateral distal forearm. (D) Postoperative view after arterialized venous flap surgery showing good contour and circulation of flap. (E) to (G) Postoperative view of the donor site and the recipient site 72 mo later, showing that the flap site coordinated with surrounded soft tissues and donor site without complications.

4. Discussion

Most tumors of the hands are benign. However, malignant hand tumors present a significant challenge to surgeons and require a multidisciplinary approach from diagnosis to treatment.^[7,19–21] As with other musculoskeletal tumors, the primary goal for malignant hand tumors is to achieve local control achieved through wide excision with adequate negative margins.^[21,22] Such treatments often result in amputation, leading to functional impairments and a significant decline in patient’s quality of life.^[19] However, advancements in imaging tools and treatment options, along with chemotherapy and radiation therapy, have enabled more precise tumor resection and adjuvant treatments. Furthermore, the development of microsurgery has led to the concept of preservative and limb-sparing surgeries involving the reconstruction of soft tissue defects following tumor excision.^[1,2,7,8,22] Outcomes of these preservative surgeries depend on whether adequate tumor resection with appropriate margins has been achieved and successful coverage of the resulting soft tissue defect.^[1,2]

A variety of reconstruction methods have been attempted, including skin grafting, local flaps, distant flaps, and free flaps using vascular pedicles. The choice of reconstruction method depends on factors such as the size and location of the defect; exposure of surrounding structures such as neurovascular bundles, ligaments, tendons, and bones; and the timing of reconstruction.^[23] Among these, venous free flaps have been introduced as a favorable surgical option for hand reconstruction because of their thin, hand-like texture and versatility in templating flap size and shape for application to any defect. Additionally, surgery with venous free flaps could use a long vascular pedicle without sacrificing major vessels. In addition, venous free flaps are are easier to harvest than conventional free flaps, leading to a shorter operative time.^[9–16,24] However, there have been relatively few reports on the use of arterialized venous free flaps for reconstruction after soft tissue tumor resection.

Woo et al^[15] have reported the outcomes of arterialized venous free flap reconstruction after wide local excision in 17 patients with subungual melanoma. Over an average follow-up period of 75.5 months, recurrence was observed in 3 of the 17 patients, and distant metastasis was found in 1 patient. However, no specific complications were associated with the flap surgery site. They reported that arterialized venous free flaps had several advantages, including minimal donor site morbidity, ease of design, good flap texture, and superior padding effect, compared to skin grafts. We also found a case of a patient with malignant melanoma who developed distant metastasis in the ipsilateral forearm 12 months postoperatively. However, no specific abnormalities were observed at the flap recipient site. Adequate wide resection is crucial for reducing recurrence and metastasis after malignant tumor resection in the upper extremities.^[21,22] Blessley-Redgrave et al^[25] have emphasized the importance of wide local excision down to the periosteal section to reduce the risk of local recurrence.

For arterialized venous free flap after tumor resection, Park et al^[16] have reported results of reconstruction using arterialized venous free flaps in 12 cases of digit skin cancer (including 5 cases of malignant melanoma and 7 cases of squamous cell carcinoma) after tumor excision. They found that arterialized venous free flaps were thin, well-matched in color to the hand, easy to operate, and could be easily tailored to the appropriate size and shape for any defect, making them a useful and reliable method for reconstruction after digit skin cancer excision. Additionally, there was no recurrence or metastasis during a mean follow-up period of 26 months. However, partial necrosis due to congestion was reported in 3 out of 12 cases on the 5th postoperative day. All of these cases involved patients who had undergone anastomosis of 1 afferent vein and 1 efferent vein. They recommended anastomosing 2 or more efferent veins and using a proximal vein with reversed blood flow as an afferent vein to improve the survival rate of arterialized venous free flaps. We anastomosed 1 efferent vein only in 1 patient, whereas 2 or more efferent veins were anastomosed in other patients. However, the afferent vein was anastomosed using the antegrade prefusion technique in all patients. In another report, Park et al^[24] have performed venous free flap for soft tissue coverage in 8 patients with facial skin cancer after excision. There was no recurrences or metastases in 7 patients, with a mean follow-up period of 33 months. They reported good or excellent results in terms of color, contour, texture, and distortion of surrounding structures. They suggested that pliable and thin venous flaps would be ideal for covering the 3-dimensionally complex facial structure. They also highlighted the versatility of harvesting and a low morbidity of the donor site.

Despite these advantages, reports on reconstruction using venous flaps after tumor resection are relatively few, suggesting that they have not yet become the treatment of choice for microsurgical reconstruction. This is because different hemodynamics compared with conventional free flaps can lead to postoperative edema, congestion, and necrosis.^[14–16,24] Woo et al^[11] have reported that altered hemodynamics in venous flaps can facilitate the accumulation of toxic metabolites and deoxygenated hemoglobin, which can lead to flap necrosis. Therefore, various modification techniques and strategies have been developed to increase the survival rate of venous flaps.^[15,16,26] Moshammer et al^[26] have performed a human cadaver study and found that venous flaps with retrograde perfusion and reversed valve direction showed better results. Park et al^[16] have also recommended using a proximal vein as the afferent vein for reverse-direction blood flow. However, we anastomosed all patients using the antegrade perfusion method. Therefore, we believe that simply reversing the perfusion direction is insufficient to improve flap survival. Beyond these survival strategies related to the flap itself, recipient bed vascularity has been shown to play a crucial role in adequately addressing postoperative congestion through flap neovascularization.^[11] Lee et al^[13] have reported that even in cases with an avascular or insufficiently vascularized recipient bed, good peripheral recipient bed vascularity and the absence of infection can lead to successful outcomes without complications in a study of 35 patients with hand trauma patients. Unlike trauma cases, an arterialized venous free flap after soft tissue tumor resection could overcome the contraindications of venous free flaps and present good results without concerns about the perfusion direction of flaps due to the excellent vascularity of the recipient bed. Thus, we believe that it could be a valuable treatment option for reconstruction after soft tissue tumor resection. Beyond demonstrating the utility of venous free flaps in digit tumors, as shown in previous studies, our research also indicated that these flaps could be expanded to reconstruct larger defects following tumor resection in the dorsum and palm of the hand.

This study had some limitations. First, the small number of cases and the wide range of follow-up periods resulted in a lack of statistical significance for flap survival and recurrence/metastasis survival. In the future, it will be necessary to accumulate more data and conduct a study with more uniform and longer follow-up periods to derive the survival rates at regular intervals. Second, a case-control study comparing different coverage techniques is required to demonstrate its superiority. In addition, metastasis occurred in 1 case of malignant melanoma. Despite a multidisciplinary approach with an oncologist recommending adjuvant chemotherapy, the patient declined treatment. Although flap survival was satisfactory, metastasis-free survival was not achieved. This highlights the need for further studies with chemotherapy patients and a control group.

5. Conclusions

This study suggests that limb-sparing surgery should be performed rather than salvage techniques for soft tissue tumor surgery of the hand. The authors believe that a arterialized venous free flap is a more valuable reconstruction option than other reconstruction techniques after soft tissue tumor resection in the hand as it presents better results than a post-traumatic hand reconstruction.

Author contributions

Conceptualization: Young-Keun Lee.

Data curation: Young-Keun Lee.

Formal analysis: Ji Woong Ho, Young-Keun Lee.

Methodology: Ji Woong Ho, Young-Keun Lee.

Software: Young-Keun Lee.

Supervision: Young-Keun Lee.

Writing – original draft: Ji Woong Ho, Young-Keun Lee.

Writing – review & editing: Ji Woong Ho, Young-Keun Lee.