Reconstruction after unplanned excisions of soft tissue sarcomas using intraoperative extracorporeal autogenous irradiated bone and tendon grafts: a report of three cases

Abstract

Background

Wide resection of soft tissue sarcomas (STS) of the hand and foot is challenging due to limited soft tissue and complex anatomy. Reconstruction often requires tissue from healthy donor sites. To address this, we used intraoperative extracorporeal irradiation (ECI) of tumor-affected bones and tendons for reconstruction after wide resection. Herein, we report the oncological and functional outcomes using this technique.

Case presentation

Three patients who underwent unplanned excision of the hand or foot at another institution referred to our hospital for additional treatment.

Case 1: A 46-year-old man with extraskeletal myxoid chondrosarcoma on the dorsal aspect of the left hand underwent wide resection followed by ECI bone and extensor tendon reconstruction with free flap coverage, and subsequently required tenolysis. At 5 years, he showed no recurrence and excellent function (Musculoskeletal tumor society (MSTS) score, 100%; Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) score, 20.5).

Case 2: A 27-year-old woman with synovial sarcoma of the dorsal right hand underwent wide resection and ECI bone and extensor tendon reconstruction. Delayed bone union required secondary bone grafting. She remained disease-free at 6 years with mild functional impairment (MSTS, 80%; QuickDASH, 29.5).

Case 3: A 19-year-old woman with synovial sarcoma of the dorsal aspect of the right hallux underwent en bloc resection and ECI bone and extensor tendon reconstruction. At 4 years, she had no recurrence and excellent functional recovery (MSTS, 97%).

Conclusion

Reconstruction using ECI-treated autogenous bone and tendon grafts allows effective oncological resection while preserving limb function and avoiding donor-site morbidity. Although mild degenerative changes were observed after osteoarticular reconstruction, all patients reported satisfactory outcomes and returned to their occupations. ECI is a valuable limb-salvage reconstruction option for STS of the hands and feet.

Background

Soft tissue sarcomas (STS) are rare malignant neoplasms accounting for less than 1% of all malignancies. STS usually occur in the trunk and proximal extremities, with less than 3% occurring in the hands and feet [1–3]. Although multimodal therapies, including surgery, chemotherapy, and radiotherapy, are used in the management of STS, wide surgical resection with negative margins remains the primary treatment. However, such extensive resection can damage surrounding normal tissues and requires complex reconstruction to preserve function [1–3]. In hand and foot lesions, complex anatomy, limited soft tissue volume, and barrier complicate achieving wide resection with an adequate margin, reconstructing skin defects, and preserving function simultaneously [1–3]. In addition, unplanned excisions (UEs) are frequently performed on the lesions of hand and foot, further complicating management [2, 4]. Because UEs often occur in hospitals where STS are infrequently treated, insufficient familiarity with appropriate STS management may lead to inadequate surgical margins (R1 or R2 resection). This, in turn, increases the risk of local recurrence and distant metastasis [4, 5]. Therefore, additional wide resection with an adequate surgical margin (R0 resection) should be considered to ensure complete removal of residual disease following UEs. However, compared with planned excisions, additional wide resection often requires more extensive resection due to the need to remove potentially contaminated tissues, which consequently increases the complexity of reconstructive procedures [5, 6].

Some reconstruction techniques for patients with STS in hand or foot lesions require incisions outside the surgical field [1, 7, 8]. To address this, we reconstructed bone and tendon defects using intraoperative extracorporeally irradiated (ECI) autogenous bone and tendon grafts. The primary advantage of this reconstructive method is that it utilizes the bone and tendon affected by the tumor, thereby avoiding additional invasion of normal tissues [9]. In this study, we clarified the functional outcomes and complications of irradiated bone and tendon grafts.

Case presentation

Case 1

A 46-year-old man presented with a mass on the dorsum of the left hand 2-years ago. Magnetic resonance imaging (MRI) revealed a mass in the second and third metacarpal bones (Fig. 1A, B). The tumor was considered benign and resected at another hospital. However, the pathological diagnosis based on the surgical specimen was extraskeletal myxoid chondrosarcoma and the patient was referred to our hospital for treatment. Physical examination revealed surgical scars, but no residual mass in the lesion. MRI also demonstrated no evidence of residual tumors (Fig. 1C). Based on the American Joint Committee on Cancer (AJCC) 8th edition [10], the clinical stage was Stage II. Because an intratumoral resection was performed at the previous hospital, an additional wide resection including the surgical scar was planned for the patient. Considering pre-operative MRI, the tumor was adjacent to the surface of metacarpal and basal bones. Thus, we considered the surface of these bones were contaminated with the tumor cells. During surgery, en bloc resection, including the metacarpal bone of the ring finger and extensor digitorum communis of the middle, ring, and little fingers, was performed (Fig. 2A). The resected specimen was moved to a separate table and unnecessary tissue was isolated from the bones and tendons. The specimens were sealed in a plastic container with saline-containing antibiotics. The container was sent to the radiology department and ECI with a single dose of 80 Gy was administered. The autografts were returned to the operating table within 50 min. The irradiated bone was reimplanted and fixed with a plate (Fig. 2B). The tendons were sutured with 4-strand suture technique at the proximal site and figure-of-eight sutures distally (Fig. 2C). The skin defect was covered with a groin free flap (Fig. 2D). The pathological examination demonstrated scattered short spindle cells with a myxoid stroma are present in fibrous tissue. Residual extraskeletal myxoid chondrosarcoma was diagnosed, with an R0 surgical margins (Fig. 2E). Postoperative radiography revealed good reduction and fixation (Fig. 3A). Postoperatively, the wrist, metacarpophalangeal (MP) joints, and proximal interphalangeal (PIP) joints were immobilized in extension for 1 week, after which active range-of-motion exercises were initiated using a cock-up splint. Nighttime immobilization in extension was continued for an additional 2 weeks. From the third postoperative week, range-of-motion exercises of the wrist were initiated. Postoperative radiographs were routinely evaluated at monthly follow-up visits in the outpatient clinic until bone union was achieved. After bone union, patients were followed at three-month intervals until three years postoperatively. Bone union of the inlay graft was defined as radiographic confirmation of the disappearance of the original gap. Eight months after the initial surgery, the patient underwent revision surgery for tendolysis of extensor digitorum communis III to V due to MP joint contraction and flap debulking. Active range-of-motion exercises were started on the day after tenolysis, while immobilization in extension was applied only at night. Although two more debulking surgeries, the patient demonstrated no local recurrence 5 years post-surgery. Radiographs at 5 years demonstrated no osteoarthritic changes or subluxation (Fig. 3B). The metacarpophalangeal joint range of motion at the final visit was good, with flexion of 80 ° and extension of 20 ° (Fig. 3C, D). Functional outcomes measured using the Musculoskeletal Tumor Society (MSTS) evaluation system and Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) Japanese edition. The patient demonstrated good outcomes, with an MSTS and QuickDASH scores of 100%, and 20.5/100, respectively. The patient continues working in the office.

Fig. 1.

Magnetic resonance imaging (MRI) findings of 46-year-old man with extraskelelal myxoid chondrosarcoma in the dorsum of his hand. Axial MRI before the initial surgery reveals a high-intensity mass on T2-weighted images of the third and fourth metacarpal bones (A). The tumor was adjacent to fourth metacarpal bone (arrow heads). Sagittal MRI showed the tumor did not extend beyond the metacarpal bone (B). MRI after the initial surgery reveals no obvious mass in the lesion (C)

Fig. 2.

Intraoperative images and microscopic photo of patient 1. Intraoperative photos demonstrate that additional wide resection was successfully performed (A), irradiated bones were fixed with a plate (B), irradiated tendons were sutured (C), and skin defects was covered with a groin flap (D). Histopathological examination showed scattered short spindle cells associated with a myxoid stroma in fibrous tissue (E)

Fig. 3.

Postoperative findings of patient 1. Radiography immediately after surgery (A) and 5 years post-surgery (B) demonstrated that the irradiated bone was successfully reduced and fixed with a plate (A), and the irradiated bones achieved union with no osteoarthritic change (B). The patient was able to hold and completely open their hands (C, D)

Case 2

A 27-year-old woman presented with a mass on the dorsum of the right hand 2-years ago (Fig. 4A). The tumor was diagnosed as benign and resected at another hospital. However, a pathological diagnosis of synovial sarcoma was made, and the patient was referred to our hospital for additional treatment. Physical examination revealed surgical scars on the dorsal middle finger with no mass observed. MRI demonstrated postoperative changes but no residual tumor (Fig. 4B). According to preoperative MRI, the patient was diagnosed as stage II. In the absence of an operative record, it was unclear how the tumor had been resected at the previous hospital. Thus, an additional wide resection was performed considering the possibility of residual tumor. Based on the preoperative MRI (Fig. 4A), the tumor was adjacent to the surfaces of the metacarpal and basal bone of middle and ring. Therefore, the surfaces of these bones were considered to be contaminated with tumor cells. En bloc resection of the tumor was performed using the metacarpal and basal bones of the middle and ring fingers, and the extensor tendons of the index, middle, ring, and little finger (Fig. 4C).

Fig. 4.

A 27-year-old woman with synovial sarcoma on the back of her han. Magnetic resonance imaging (MRI) before the initial surgery reveals a high-intensity mass on gadolinium-enhanced T1-weighted images of the third and fourth metacarpal bones (A). The tumor was adjacent to the metacarpal and basal bone of middle and ring (arrow heads). MRI after the initial surgery demonstrates no residual tumor in the lesion (B). Intraoperative images demonstrate that additional wide resection was successful (C), and irradiated bones and tendons were reconstructed with plates and wires (D). Histopathological examination demonstrated proliferation of collagenous fibrous tissue (E)

The resected tendons and bones were irradiated as in patient 1. The irradiated bones were reimplanted and fixed with wires and plates. The tendons were sutured with 4-strand suture technique using a tsuge suture at the proximal end and figure-eight sutures at the distal end (Fig. 4D). The skin defect was covered with a free groin flap. Postoperative histopathological examination revealed only scar tissue, with no residual tumor identified (Fig. 4E), and we considered that an R0 resection was achieved. Postoperative radiographs are shown in Fig. 5A. Postoperatively, the wrist, MP joints, and PIP joints were immobilized in extension for 2 weeks. From week 3, active range-of-motion exercises were initiated using a cock-up splint. An outrigger splint was made in the third postoperative week, allowing active and passive distal interphalangeal (DIP) and PIP joint motion, with MP joints maintained in extension. Mild MP joint mobilization was initiated at week 4, light activity at week 5, simultaneous finger flexion at week 8, and grip strength at week 9.

Fig. 5.

Radiographic images of patient 2. Although radiography immediately after wide resection demonstrated successful reduction and fixation (A), radiography performed 6 years after surgery showed osteoarthritic changes (allow heads) and dislocation at the metacarpophalangeal joint of the middle finger (B)

Based on the clinical stage and the pathological findings from the additional surgery, no perioperative chemotherapy was administered. The patient was followed up in the same manner as patient 1. Radiographic union of the osteoarticular graft was defined by the presence of bone bridging across at least three of the four cortices on biplanar radiographs. Postoperatively, the third phalanx and metacarpal achieved union, whereas the fourth phalanx and metacarpal were nonunion. Eight months postoperatively, bone grafting was performed on the fourth phalanx and metacarpal bone. Immobilization in extension was maintained for 2 weeks, after which active range-of-motion exercises were initiated. Six years after an additional wide resection, osteoarthritic changes and dislocation occurred at the metacarpophalangeal joint of the middle finger (Fig. 5B). However, the patient demonstrated extension contracture at the metacarpophalangeal joint of the middle and lower fingers and dislocation of the metacarpophalangeal joint of the middle finger. She continued working in her administrative position without difficulties in her daily life. The patient had no recurrence or metastasis. The MSTS and QuickDASH scores were 80%, and 29.5/100, respectively.

Case 3

A 22-year-old woman visited our hospital with pain in the dorsal aspect of the right hallux. However, imaging revealed no abnormalities. Two years later, a mass was detected on the dorsum of the right hallux. The patient revisited the initial hospital, where the tumor was resected without imaging. The pathological diagnosis was synovial sarcoma, and the patient was referred to our hospital for further treatment. According to the pathology report, the tumor measured approximately 24 mm, and the patient was diagnosed with clinical stage II disease. Physical examination revealed surgical scars, and no mass was observed. Although MRI also showed no oblivious residual tumor, the post-operative change was observed on the surface of proximal phalanx and metatarsals of the hallux (Fig. 6A). Because the operative record from the previous hospital suggested the presence of residual tumor capsule, we considered the dorsal aspect of these bones were contaminated with the tumor cells. An additional wide was the carried out for the patient. During the surgery, En bloc resection of the tumor at the dorsal aspect of the proximal phalanx and metatarsals of the hallux, extensor hallucis longus, and extensor hallucis brevis was performed (Fig. 6B). The resected bones and tendons were irradiated as in previous cases and reimplanted. Irradiated bones were fixed using cortical screws. Tendons were sutured with a 4-strand suture technique using a tsuge suture at the proximal end and figure-of-eight sutures at the distal end (Fig. 6C). Postoperative radiographs showed successful reduction and fixation with screws (Fig. 6D). The skin defect was covered with a free groin flap. Postoperatively, the patient rested for 1 week, followed by immobilization in extension for 3 weeks, with weight-bearing up to 30 kg permitted. Full weight-bearing and range-of-motion exercises were initiated at postoperative week 4. Pathological examination revealed no evidence of residual tumor, suggesting that an R0 resection was achieved. Based on this observation, perioperative chemotherapy was not administered. The patient was followed up in the same manner as patient 1. Seven and eleven months postoperatively, flap debulking surgery was performed. Four years after the additional wide resection, no local recurrence was observed. Although radiography showed osteoarticular change at interphalangeal joint of the hallux (Fig. 6E), the patient demonstrated no restriction in the range of motion (Fig. 6F); her MSTS score was 97%, and she worked as a nurse. Patient demographics, tumor characteristics, bone and tendon reconstruction methods, and clinical outcomes are summarized in Tables 1 and 2.”

Fig. 6.

A 19-year-old woman with synovial sarcoma in the dorsum of the foot. Magnetic resonance imaging (MRI) after the initial surgery revealed a high-intensity area (arrow heads) with no residual tumor on T2-weighted imaging on the dorsum of the right hallux (A). Intraoperative images show successful additional wide resection (B), and reconstruction of the irradiated bone and tendons (C). Radiography immediately after wide resection demonstrated successful reduction and fixation with screws (D). Although radiography performed four years after the surgery showed osteoarthritic changes at the metatarsophalangeal joint (E), the patient is able to dorsiflex the big toe (F)

Table 1.

Summary of patient demographics and tumor characteristics

Patient	Age/Sex	Location	Size (mm)	Stage	Histology	Residual tumor (Postoperative MRI)	Follow-up period (Months)
1	46/man	Dorsal hand	20	II	Extraskeletal myxoid chondrosarcoma	No	64
2	27/woman	Dorsal hand	18	II	Synovial sarcoma	No	74
3	22/woman	Dorsal foot	24	II	Synovial sarcoma	No	53

MRI Magnetic resonance imaging

Table 2.

Bone and tendon reconstruction methods and clinical outcomes

Patient	Resected bone	Type of bone grafting	Resected tendon	Skin flap	Residual tumor(Pathologically)	Local recurrence	Complications	Additional surgeies	MSTS, QuickDASH	Outcomes
1	Metacarpal (IV)	Inlay	EDC (III-V)	Groin flap	Yes	No	Contracture, bulkiness	Tendolysis, Flap debuling	100, 20.5/100	CDF
2	Metacarpal and basal (III, IV)	Osteoarticular	EIP, EDC (II-V)	Groin flap	No	No	No-union	Bone grafting	80, 29.5/100	CDF
3	Phalanx and metatarsal (I)	Inlay	EHL, EHB	Groin flap	No	No	Bulkiness	Flap debulikng	97, N/A	CDF

EDC Extensor digitorum communis, EIP Etensor indicis proprius, EHL Extensor hallucis longus, EHB Extensor hallucis brevis, MSTS Musculoskeletal tumor society, QuickDASH Quick Disabilities of the Arm, Shoulder and Hand score, N/A Not available, CDF Complete disease free

Discussion and conclusions

Local control of STS is achieved by surgical resection with adequate wide margin [11], while preserving function in hand and foot lesions is challenging due to complex anatomy, compact compartments, and high density of critical structures [2, 12]. As STS of the hand and foot are uncommon, they are often not initially considered in differential diagnosis. Consequently, these tumors have historically had a high rate of UEs, leading to increased likelihood of amputation [13].

Recently, owing to advances in imaging, reconstruction techniques, and adjuvant therapy, limb salvage surgery has been increasingly performed in patients with hand and foot sarcomas, with good functional outcomes [7, 12, 14]. Reconstruction procedures such as tendon transfers [7] and vascularized fibula grafting [7, 8] have been performed in patients with STS in hand and foot lesions. However, these techniques require invasion of unaffected tissues. To address this, bone and tendon defects resulting from wide resection of the STS were recycled using intraoperative ECI grafts, yielding favorable outcomes at other sites [9, 15, 16]. A major advantage of reconstruction using irradiated tendons is the avoidance of donor site morbidity and the ability to restore native ligaments to their original shapes, sizes, and anatomical locations. Consequently, this method demonstrates favorable functional outcomes in patients with extensor tendon involvement [16].

UEs frequently occurred in lesions of the hand and foot [2, 4]. Although UEs are logically expected to influence local recurrence, distant metastasis, and patient survival [5], their actual impact of UEs remains controversial. Consequently, the necessity and optimal timing of additional wide resection continue to be matter of debate [5]. In the current study, MRI after UEs in all three patients demonstrated no evidence of residual tumors. However, the reported sensitivity and specificity to detect residual tumor using MRI ranges from 64% to 86.7%, and from 57.9% to 93% respectively [5, 17, 18]. These findings indicate that distinguishing residual tumor form postsurgical changes remains challenging. Indeed, in patient 1, residual tumor was pathologically confirmed at the time of additional wide resection, despite preoperative MRI suggesting no residual tumor. Furthermore, operative notes from the initial surgeries suggested a possibility of residual tumor, which prompted us to perform additional wide resection without delay.

As irradiated tendon grafts recycle tumor-affected tendons, local recurrence is the main concern with this technique. To avoid the risk of local recurrence, reconstruction using iliac crest or fibular bone grafts is another option, and favorable functional outcomes have been reported [19, 20]. However, increasing the number of donor sites may also increase the risk of iatrogenic implantation [21]. Clinical tumor sterilization was achieved with a bolus dose of 50 Gy of radiation [16]. In addition, our colleagues evaluated irradiated autografts that received a single radiation dose of 60 Gy and demonstrated, through histological analysis, complete eradication of viable tumor cells within the grafts [22]. However, because our unpublished animal experiments demonstrated local recurrence at 60 Gy, we increased the radiation dose to 80 Gy. Our previous experience with irradiated bone grafts showed no local recurrence at either 60 Gy and 80Gy [9], and none of the three patients in this study demonstrated recurrence. In contrast, Omori et al. reported that one of four patients reconstructed using an irradiated tendon experienced local recurrence [16]. However, this patient developed local recurrence outside the irradiated graft, and marginal resection was performed initially to preserve function. Although the presence of microscopic residual tissue is not described in the paper, the findings suggest that irradiated bone and tendon grafting did not lead to local recurrence, while insufficient margins were more strongly contributed to recurrence. Several published long-term observational studies of extracorporeal irradiation (ECI) bone grafting have demonstrated that local recurrence is rare within the irradiated graft itself. No recurrences originating inside the irradiated bone have been reported, while local recurrences have occurred predominantly in the surrounding soft tissues, likely due to insufficient surgical resection, supporting this concept [9, 23, 24].

Perioperative chemotherapy may be considered especially for patties with synovial sarcoma (patient 2 and 3), because synovial sarcoma is a relatively chemo-sensitive STS. However, at the time of the initial surgery, the tumor sizes in patients 2 and 3 were less than 2 cm and 3 cm, respectively. Moreover, pathological examination at additional wide resection demonstrated no residual tumor. Taken together that the usefulness of chemotherapy in patients with synovial sarcoma who underwent R0 resection for tumors less than 5 cm in size remains unclear, chemotherapy was not administered to either patient.

Adjuvant radiotherapy might be considered for patients with UEs. Generally, adjuvant radiotherapy contributes to reducing local recurrence rate and may be considered for patients with UEs after additional wide resection [5]. However, in this study, no patients received perioperative radiation for the following reasons. Because of limited usage of adjuvant radiotherapy in Japan, the efficacy of adjuvant remains undetermined in our country [5]. In addition, in the current study, patient 1 demonstrated residual tumor of extraskeletal myxoid chondrosarcoma, but R0 resection was achieved. Patient 2 and 3 showed pathologically no evidence of residual tumor. Taken together with these reasons, we considered that adjuvant radiotherapy may be overtreatment for our patients.

Frozen autografts are another recycled technique [25] for devitalizing tumor-affected tendons. However, to the best of our knowledge, frozen autografting has only been used for the reconstruction of relatively large tendons, such as the patella ligament [26], with no reports for hand or foot tendons. Altogether, no difference was observed in the incidence of tumor recurrence and functional outcomes derived from irradiation- or frozen-treated autografts [27], ECI may have the potential advantage of sterilizing affected bones and tendons simultaneously in lesions of hand and foot. In the current series, patients 1 and 3 demonstrated excellent functional outcomes with MSTS scores of 100% and 97%, respectively. In contrast, patient 2, which was reconstructed using an osteoarticular graft, showed a poorer functional outcome, with an MSTS score of 80%. This finding is consistent with previous reports indicating that functional outcomes following osteoarticular grafting using ECI are inferior to those achieved with inlay and intercalary grafts [9], that such outcomes may be less favorable for hand lesions. In addition, because bone resection was limited in all cases and sufficient healthy host bone was preserved, the favorable functional outcomes observed in this series may not be directly applicable to patients requiring more extensive bone reconstruction. However, the patient reported no limitations in daily activities and returned to her previous occupation. As the hand is a non-weight-bearing, articular surface collapse may be less significant than that in other joints. Reported postoperative functional outcomes vary widely across studies. Labow et al. described a series including three patients with soft tissue sarcoma of the hand reconstructed by tendon transfer, in whom the mean MSTS score was 63.3% [28]. In contrast, Kim et al. reported a mean MSTS score of 73% in patients with upper-extremity soft tissue sarcoma who underwent microvascular reconstruction [12], while Muranetto et al. reported more favorable functional outcomes in patients with sarcoma of the hand, with a mean MSTS score of 92% [29]. Regarding the foot, Kozawa et al. reported the functional outcomes of sarcomas arising in the forefoot, with a mean MSTS score of 86% [1]. Ozaki et al. performed ECI bone and tendon grafting in a patient with myxoid liposarcoma of the dorsal foot. The patient achieved an MSTS score of 74% at 36 months of follow-up, with no evidence of local recurrence [30]. In summary, although the small number of cases requires cautious interpretation, the outcomes of our patients were comparable to those reported in previous studies, suggesting that ECI autologous reconstruction may represent a useful option in carefully selected patients.

Although the long-term strength of irradiated tendons was not fully elucidated, histological examination revealed fibroblast-like cells within collagen strands, suggesting morphologically normal tendon [22]. In addition, two studies have reported follow-up periods of at least 10 years for ECI bone grafting, and those studies demonstrated favorable long-term outcomes of irradiated bone grafts [9, 24], and histological analysis showed the viability of irradiated tendon [9], suggesting these grafts can maintain long-term function.

Considering that all three patients required additional surgery, some degree of complication may be unavoidable in patients reconstructed with ECI bone and tendon grafts. However, the postoperative complication rate after surgery for soft tissue sarcoma of the hand is high, ranging from 27% to 73% [31]. The most common complications include neuroma formation, joint contracture, and tendon adhesions. In our series, patient 1 required surgical intervention for tendon adhesions. Patient 2 developed nonunion in irradiated bone and required bone grafting, and nonunion may be more frequent after ECI bone grafting. Nevertheless, patients 1 and 2 each required only a single reoperation for functional reconstruction within one year after additional wide resection, whereas patient 3 underwent only flap debulking surgery for aesthetic purposes. In our previous report on reconstruction using ECI bone grafting, although the reoperation rate was relatively high, most revision surgeries occurred within five years postoperatively [9]; the present findings are consistent with those results. As the additional surgeries in the current series were performed during the early postoperative period, ECI may still represent a potentially valuable treatment option from a long-term perspective, particularly for younger patients.

The optimal indications for ECI autografts remain controversial. Jones et al. emphasized that appropriate patient selection is essential and should be based on thorough evaluation of the surgical margins, available bone stock, and the anatomical location [32]. Otani et al. further noted that ECI autografts are best suited for patients with a favorable prognosis who are expected to derive long-term benefit [24]. We agree with these statements and suggest that appropriate candidates for reconstruction in the hand or foot include patients in whom secure surgical margins can be achieved, as well as those requiring reconstruction of multiple tendons or bones, those in whom preservation of other donor sites is desirable in anticipation of additional reconstruction, those amenable to inlay grafting, and younger patients with a longer life expectancy.

This study has several limitations. First, it includes a small number of cases involving a wide range of anatomical sites and was conducted in a retrospective setting. Second, all three cases involved unplanned excision; therefore, it remains unclear whether these findings are applicable to other anatomical sites or to initial surgical procedures. In addition, the relatively small tumor size in the present cases may have contributed to the favorable oncologic outcomes. Nevertheless, despite the need for further evaluation in a larger series, we consider this technique to represent a potential reconstructive option.

In conclusion, we performed irradiated bone and tendon grafts in patients with STS in lesions of the hand and foot. Although additional surgeries were required for all three patients, they showed no local recurrence with favorable function. While further studies are warranted, our findings suggest that ECI bone and tendon grafting may be a feasible and potentially effective reconstructive option for limb salvage surgery in patients with STS of the hands and feet, particularly in younger patients.

Abbreviations

STS

Soft tissue sarcomas

UE

Unplanned excision

ECI

Extracorporeal irradiation

MSTS

Musculoskeletal tumor society

QuickDASH

Quick Disabilities of the arm, shoulder and hand

MRI

Magnetic resonance imaging

MP

Metacarpophalangeal

PIP

proximal interphalangeal

DIP

distal interphalangeal

Authors’ contributions

Conceptualization, N.O.; design of the work, N.O., A.O., and H.K.; data acquisition, analysis, N.T., N.O., T.A., and T.Y.; interpretation of data, N.O., H.K. and A.O.; Writing original draft, N.T., N.O., and T.A.; all authors have read and agreed to the published version of the manuscript.

Funding

No funding was for the preparation of this manuscript.

Data availability

The datasets used and/or analyzed in this study are available from the corresponding author upon reasonable request.

Ethics approval and consent to participate

This study was approved by the Institutional Review Board of Niigata University Graduate School of Medical and Dental Sciences (Approval number 2025-0023). Written informed consent was obtained from all participants.

Consent for publication

Written informed consent for publication was obtained from all participants.

Competing interests

The authors declare no competing interests.