Tumors of the foot and ankle: analysis of 196 cases

Osseous tumors of the foot, ankle, and lower leg: a cross-sectional observational study analysing 288 cases

BACKGROUND

Osseous tumors of the foot and ankle are rarely encountered in general orthopaedic practice and represent only 3 % of osseous neoplasms. It can be difficult to distinguish between benign and malignant lesions, leading to misdiagnosis. Delays in diagnosis are the main cause of litigation in sarcoma of the extremities. Poor understanding of how sarcomas present in this region can lead to inappropriate initial procedures, limiting options for limb salvage and increasing rates of local recurrence. Our aim is to improve understanding of these rare tumors to reduce misdiagnosis and decrease the occurrence of inappropriate or unwarranted procedures.

METHODS

We retrospectively analysed a prospectively maintained database of 288 new referrals to the West of Scotland regional musculoskeletal oncology service for osseous lesions of the foot, ankle and lower leg over a 10-year period. An analysis of patient demographics, presentation, anatomical location, diagnosis, classification, management and outcomes was performed.

RESULTS

Of all new referrals, 52.4 % were diagnosed with primary benign osseous tumors, 8.7 % with primary malignant osseous tumors, 9.7 % with metastatic osseous lesions, and 29.2 % pseudotumors. The most common primary benign tumor in our population was osteoid osteoma (18.5 %), primary malignant tumor was osteosarcoma (32 %) and metastatic osseous lesions were from small cell lung cancer primary (14.3 %). In the foot and ankle, malignant bone tumors most commonly presented in the distal tibia and fibula (20 %). Rest pain was the most common symptom at presentation in all groups, followed by swelling. The average duration of symptoms was 5 months for malignant lesions before primary referral.

CONCLUSION

Bone tumors in the foot and ankle remain a diagnostic challenge. We hope to have increased understanding of these rare lesions and have recommended a management protocol in order to reduce the number of inappropriate procedures performed, optimising clinical outcomes and reducing the cost of litigation to healthcare services.

LEVEL OF EVIDENCE

Level III- Cross-sectional observational study.

Extensive Osteochondroma of the Talus Presenting As Syndesmotic Joint Extension and Posterior Inferior Tibiofibular Ligament Rupture: A Reportof a Rare Case and a Review of the Literature

This case report describes a rare occurrence of talar osteochondroma extending into syndesmosis, causing disruption of the interosseous membrane and the posterior inferior tibiofibular ligament (PITFL). This type of presentation for a talar osteochondroma is the first of its kind reported in the literature based on current knowledge. A detailed preoperative radiological assessment was crucial in planning the surgical approach and preparing for syndesmotic stabilization during the excision. The patient underwent successful and complete excision of the osteochondroma, and the syndesmosis was stabilized using a cortical screw along with anatomical repair of the PITFL. Apart from delayed wound healing, the patient exhibited good functional outcomes in terms of gait and ankle range of motion at the six-month follow-up. This case serves as a valuable reference for similar presentations in the future, emphasizing the importance of thorough preoperative assessment and appropriate treatment planning.

Insights into the Distribution Patterns of Foot and Ankle Tumours: Update on the Perspective of a University Tumour Institute

The rarity of foot and ankle tumours, together with the numerous histological entities, presents a challenge in accumulating sufficient patients to draw reliable conclusions. Therefore, we decided to present an update of a retrospective analysis of their distribution patterns, comprising 536 cases of foot and ankle tumours presented to our tumour board between June 1997 and June 2023. Our aim was to provide a comprehensive overview of the prevalence and distribution patterns of benign and malignant bone and soft tissue tumours of the foot and ankle. A total of 277 tumours involved bone (51.7%). Of these, 242 (87.4%) were benign and 35 (12.6%) were malignant. In addition, 259 soft tissue tumours (48.3%) were found, of which 191 (73.7%) were benign and 68 (26.3%) were malignant. The most common benign bone tumours were simple bone cysts, enchondromas, osteochondromas, aneurysmal bone cysts, and lipomas of bone. Common benign soft tissue tumours included a tenosynovial giant cell tumour, haemangioma, plantar fibromatosis, schwannoma, and lipoma. The most common malignant soft tissue tumours were synovial sarcoma, malignant melanoma, and myxofibrosarcoma. In terms of anatomical location, the hindfoot was the most common site (28.7%), followed by the midfoot (25.9%), ankle (25.4%), and forefoot (20.0%). The distribution of benign entities often follows typical patterns, which may facilitate an early diagnosis even without biopsy (e.g., simple bone cyst, plantar fibromatosis). On the other hand, the distribution patterns of many rare or malignant entities are inconsistent. Individual soft tissue malignancies occur very sporadically, even over long periods of time and in specialized tumour centres. It is therefore important to recognise that any suspicious mass in the foot and ankle must be considered a possible malignancy until proven otherwise.

Tumours of the foot: A 10 years retrospective analysis

INTRODUCTION

The foot is a complex structure composed of several tissues, each of which can be the origin of the proliferation and development of the tumour. Most lesions about the foot are reactive or inflammatory, but some are true neoplasms.

METHOD

This is a retrospective analysis of 4997 patient records treated in the Orthopaedic Oncology Unit of University Malaya Medical Centre, Malaysia, between 1 January 2010 to 31 December 2020. Demographic data of 195 patients with foot tumours were analysed out of 4997 neoplasm patients.

RESULTS

There were 195 cases of foot tumours: 148 were benign, and 47 were malignant. 47 were bone tumours, 4 were metastases, and 144 were soft tissue tumours. Six patients succumbed to the disease, two cases of giant cell tumour (GCT) and one patient with synovial sarcoma had a recurrence. Treatment of foot tumours was wide resection in general. However, in metastasis cases, amputation was done. The majority of tumours were in the toes and dorsum of the foot. Soft tissue tumours of the foot occur in the elderly population in contrast to bone tumours, mainly in the second decade of life. The gender distribution was almost equal for foot tumours. Ganglion and Giant Cell Tumour of the bone are the commonest benign soft tissue and bone tumours. The most common malignant soft tissue and bone tumours are malignant melanoma and chondrosarcoma. The amputation rate is 5.64% the recurrence rate is 1.54%. Mortality rate is 3.08%. The MSTS score is 79%, and the TESS score is 76.23%.

CONCLUSION

Foot tumours are relatively rare, mostly originating from soft tissue and exhibiting a benign nature. Nonetheless, a noteworthy proportion-approximately a quarter of these tumours-demonstrate malignancy. The surgical interventions undertaken in managing these tumours and associated functional outcomes generally yield acceptable results.

RESECTION OF ANKLE TUMOR LESION AND RECONSTRUCTION WITH THE USE OF ALLOGRAFT

Reconstruction of the distal third of the tibia due to resection of a malignant tumor has some hindering factors, such as a thin subcutaneous layer, neurovascular bundles that cross compartments, prolonged operative duration, specific orthopedic material, and a trained multidisciplinary team. Allografting with material from tissue banks is part of this orthopaedic arsenal.

OBJECTIVE

To describe the protocol used at Instituto Nacional de Traumatologia e Ortopedia Jamil Haddad.

METHODS

Series of six cases subjected to resection with oncologic margins, allograft reconstruction, and use of a retrograde ankle nail as limb-salvage surgery. Three of the six patients were women, the lesions were on average 9.3 cm long, and the average operative duration was 3.25 hours.

RESULTS

The main short-term complication (≤ 30 days) was peroneal nerve palsy, while the main long-term complication (> 30 days) was surgical site infection (two cases). Consolidation of the two foci occurred in three patients, and two patients developed asymptomatic pseudoarthrosis of the proximal focus with consolidation of the distal focus.

CONCLUSION

Despite the complications, the proposed surgery gives patients the chance to preserve their limb in the face of immediate radical surgery. Level of Evidence IV, Case Series.

Malignant Bone and Soft Tissue Lesions of the Foot

Malignant tumors of the foot are rare pathologies that can involve the skin, soft tissue, or bone. Due to their rarity, they are often misdiagnosed, resulting in inadequate excision and poor outcomes. A correct approach with a careful examination and radiological study, followed by a properly performed biopsy, is thus mandatory to avoid these pitfalls. The present article reviews the most common malignant bone and soft tissue lesions of the foot region, discussing their clinicopathological presentation, imaging features, and current concepts in treatment.

EPIDEMIOLOGICAL PROFILE AND EVOLUTION OF ANKLE MUSCULOSKELETAL TUMORS

Objective

Characterizing ankle tumors, presenting the epidemiological profile of these lesions.

Methods

Retrospective observational case series study to evaluate the results of clinical and/or surgical treatments of patients with ankle tumors whose first visit occurred from 1990 to 2020. The dependent variables were: benign bone tumor, malignant bone tumor, benign soft tissue tumor, malignant soft tissue tumor, and infection. The independent variables were: sex, age; presence of symptoms (pain/local volume increase/fracture), duration of symptoms until treatment, diagnosis, treatment, and recurrence.

Results

In total, 70 patients were included-58.5% were women, with a mean age at the time of diagnosis of 21.66 years. Among all cases, 76% were bone tumor, 14% were soft tissue tumor, and 10% were infection. The mean age at the time of diagnosis was 21.7 ± 2.29 years. The overall prevalence of pain was 77.1%. In total, 55.6% patients had a general local volume increase 13.4% had fractures. The mean time from symptoms to treatment was 17.4 ± 4.61 months and the mean diagnosis time was 10.13 ± 0.86 months. Of all cases, 73.44% underwent surgical treatment and 22.64% had recurrence.

Conclusion

In this series, ankle tumors corresponded mainly to bone tumors. Benign tumors were the most prevalent type of tumor and the highest occurrence was among young people. Level of Evidence IV, Case Series.

Postoperative clinical and functional outcomes in patients with tumor and tumor-like lesion of foot and ankle

Background

Tumors and tumor-like lesions of the foot and ankle are relatively rare and their postoperative clinical outcome has not been well reported.

Methods

This study retrospectively reviewed medical records of all patients who underwent excision of tumors and tumor-like lesions of the foot and ankle from 2008 to 2020. Preoperative and postoperative clinical outcomes were evaluated by the Japanese Society for Surgery of the Foot (JSSF) scales (pain, function, and alignment).

Results

A total of 117 consecutive patients were analyzed in this study. Bone lesions accounted for 51 patients (benign: 45, intermediate malignancy: 1, malignant: 5), and soft tissue lesions accounted for 66 patients (benign: 57, intermediate malignancy: 2, malignant: 7). Four patients (8%) presenting with bone tumor and six (9%) soft tissue tumors resulted in recurrence. Eight (67%) patients with malignant lesions were alive continuously disease free and followed for a median of 50.5 (range: 18 to 82) months. Amputation at the first operation was done for five cases (33%) of malignant or intermediate malignancy (below-knee amputation: 1, Chopart disarticulation: 1, forefoot amputation: 3). Postoperative JSSF scores resulted in a significant 'positive' increase (bone lesion, 75.9 ± 13.7 to 91.4 ± 14.9, p < 0.001; soft tissue lesion, 84.7 ± 14.8 to 91.9 ± 12.5, p < 0.001). The score improvement in bone lesions was significantly higher than in soft tissue lesions (p = 0.003).

Conclusion

The surgical management of tumors and tumor-like lesions of the foot and ankle showed good post-operative functional outcomes with bone lesions exhibiting better results when compared to soft-tissue lesions.

Malignant Tumors of the Foot and Ankle

BACKGROUND

Surgical treatment is usually required for malignant foot and ankle tumors. In this study, we sought to review factors in treatment that may be associated with morbidity and mortality.

METHODS

All malignant foot and ankle tumors at our institution between April 1988 and April 2018 were retrospectively reviewed. The surgical modalities used and clinical outcomes of patients according to the anatomic location (Kirby zone) and clinical stage (Enneking system) of each tumor were described. Extent of surgical resection required, recurrence, and death rates were assessed.

RESULTS

Between April 1988 and April 2018, 80 patients with malignant tumors of the foot and ankle were treated at out institution. Mean age of patients was 42.6 (range, 3-89) years. Mean follow-up was 30.2 months (range, 24-120). Tumors were primary in 75 patients (94%) and metastatic from another organ in 5 patients (6%). Tumors originated from bone in 18 patients (22%) and from soft tissue in 63 patients (78%). Synovial sarcoma was the most common soft tissue tumor, and osteosarcoma was the most common osseous tumor.All patients had surgery to resect their tumor. Twenty-one (26%) had unplanned surgical procedures without initial biopsy at an outside institution prior to referral. Those patients were more likely to be treated with amputation or wide excison and free flap surgery (P < .01). The recurrence rate was 50% for the unplanned surgery group and 22% for the planned surgery group. Mortality rate was 10% for the unplanned group and 6% for the planned group. The recurrence and mortality rate was higher in the unplanned group (P = .03).

CONCLUSION

Our study suggests that unplanned initial surgeries are associated with higher recurrence and mortality rates and reinforces the notion that these patients should be referred for treatment at a center with specialized expertise in tumor management.

LEVEL OF EVIDENCE

Level, IV, retrospective case series.

A Study to Determine the Incidence and Distribution Patterns of Foot and Ankle Tumors in Bone and Soft Tissue

Objectives: The aim of this study is to determine the incidence and distribution patterns of foot and ankle tumors in bone and soft tissue in a university tumor institute, to help the correct evaluation of uncertain masses, to take the right steps in advanced diagnosis and treatment, and to contribute to future research.

Materials and methods: A retrospective analysis of a total of 164 foot and ankle cases examined by a multidisciplinary bone and soft-tissue tumors care team between January 2004 and December 2021 was performed from a database in which patient information was recorded in our tertiary university hospital. Thirty-three (20.1%) of 164 patients were discussed in the tumor council and evaluated as having the non-tumor disease. All of these patients were excluded from the study. A total of 131 patients diagnosed with tumors were included in this study.

Results: The lesion was determined as a benign tumor in 84 (64.1%) cases of 131 tumor patients included in the study. Of these 84 patients, 40 (47.6%) were identified as benign bone lesions and 44 (52.4%) as benign soft-tissue lesions. Malignancy was determined in 47 (35.9%) of 131 patients, affecting the bone in 14 (29.8%) patients and the soft tissue in 33 (70.2%). The malignant soft-tissue lesion most determined was malignant mesenchymal tumor in 10 (30.3%) patients, of which one had lung metastasis and one was determined with multiple metastases. Metastasis was detected in eight patients in total, including three metastatic malignant bone tumors and five metastatic malignant soft-tissue tumors.

Conclusions: Tumors involving the foot and ankle are not frequently encountered, and most tumors in this region are benign. The anatomic structure of the foot allows early diagnosis, but for diagnosis to be made, there must first be clinical suspicion. The first symptom is generally swelling. Early diagnosis can prevent several complications. Therefore, patients with foot and ankle complaints must be taken seriously and evaluated with advanced tests if necessary.

Benign and Malignant Tumors in Child Foot

Bone tumors affecting pediatric foot are a rare occurrence. Most lesions are benign, but a thorough diagnostic evaluation must always be performed to rule out malignant tumors. Approach to benign lesions is conservative, from observation follow-up to curettage or mininvasive techniques. In malignant lesions, a wide resection must be performed and same protocols applied as in tumors affecting other skeletal sites. Reconstructive procedures should aim to mechanical stability and long-lasting results; joint motion restoring can be attempted when not negatively affecting stability. Amputation procedures should be considered as a still viable choice because of their good functional result in the foot.

Clinical features of bone and soft tissue tumors of the foot and ankle: Results from a retrospective single-center case-series

BACKGROUND

The malignant potential of the musculoskeletal tumors of the foot and ankle has often been underestimated because of their rarity. The current study reviewed the clinical features of the tumors of the foot and ankle, and evaluated the tumor size via imaging-based analysis to distinguish between benign and malignant lesions.

METHODS

A retrospective review was performed using the clinical records of all patients with histologically confirmed musculoskeletal tumors of the foot and ankle, treated between 1998 and 2020 at our institution. We examined the distribution of tumors, rate of unplanned excision for primary surgery, and subsequent outcomes. In addition, the tumor size was examined via magnetic resonance imaging, and the cut-off value was determined via receiver operating characteristic (ROC) curve.

RESULTS

A total of 103 bone and soft tissue tumors of the foot and ankle were included, of which 78 were soft tissue tumors and 25 were bone tumors. Of the 14 cases of malignant bone and soft tissue tumors, 6 (42.9%) received unplanned excision in the primary surgery, followed by amputation in 3 cases. Tumor size of malignant soft tissue tumors was significantly larger than that of benign soft tissue tumors (47.6 mm vs. 31.0 mm, respectively, P < .001). However, the difference between benign and malignant bone tumors was not statistically significant with the numbers available. ROC curve determined that the optimum diagnostic cutoff value for soft tissue tumor size was 40 mm, with a high area under the ROC curve 0.816 (95% CI: 0.711-0.921, sensitivity 91.7%, specificity 70.5%) CONCLUSIONS: We highlighted that bone and soft tissue tumors of the foot and ankle were often misdiagnosed and initially inadequately treated. We suggest that a cutoff value of 40 mm may be a useful index for prediction of malignancy in soft tissue tumors of the foot and ankle.

LEVEL OF EVIDENCE

Ⅲ.

Malignant neoplasms originating from the bones of the foot: Predilection of hematological malignancies and sex-related and ethnic disparities in amputation

PURPOSE

Neoplasms originating from the "small bones of the lower limb and the overlapping joints" are rare but portend a serious prognosis. Current study utilizes a population-based registry in the United States to characterize the malignancies of the foot.

METHODS

National Cancer Institute's Surveillance, Epidemiology and End Result database from 1975 to 2017 was queried to report incidence and survival data in 514 patients in the Uited States. Kaplan-Meier and Cox Regression were used to determine the prognostic factors affecting survival. Chi square test was used to assess the correlation.

RESULTS

Hematological malignancies constituted 14.8% of the entire cohort. Incidence of the foot neoplasms was 0.024 per 100 000 persons in 2017 and has not significantly changed since 1975 (p > 0.05). Disease-specific-5-year survival for the entire cohort was 73%. On multivariate analysis younger age groups, "localized" stage and extent of surgical resection were predictors of improved outcomes. A significant correlation was found between amputation with male sex and Hispanic ethnicity.

CONCLUSIONS

The current study analyzes data from population-based registry reporting incidence and survival data for patients with neoplasms of the foot. Independent prognostic factors include age, stage and extent of surgical resection. Amputation was found to be associated with male sex and Hispanic ethnicity.

A Solitary Benign Schwannoma of the Medial Dorsal Cutaneous Nerve of the Foot Masquerading as a Ganglion Cyst

Schwannomas are rarely seen in the foot and ankle and mostly arise from the plantar aspect. Dorsal foot schwannomas are not commonly reported. We describe the case of a 25-year-old man who had a painful swelling on the dorsum of his right foot, which resembled a ganglion cyst on clinical examination and ultrasonography findings. Persistent symptoms prompted the need for an excisional biopsy, which revealed a benign schwannoma arising from the medial dorsal cutaneous nerve. Complete and careful excision relieved the symptoms without causing any distal neural deficit. Thus, schwannomas can mimic as a ganglion cyst. Excisional biopsy of such swellings, if symptomatic, helps in confirming the diagnosis, and provides a good functional outcome.

An epidemiological review of 623 foot and ankle soft tissue tumours and pseudo-tumours

BACKGROUND

In evaluating foot and ankle soft tissue masses, comprehensive epidemiological data, especially clinical predictors of malignancy, is essential knowledge. Our aim was to assess these data in a cohort of patients that have undergone surgical excision of foot and ankle soft tissue tumours and pseudo-tumours over a 10-year period.

METHODS

A retrospective review of foot and ankle soft tissue tumours and pseudo-tumours excised in a tertiary hospital from 1 Jan 2006 to 31 Dec 2016 was performed. Uni- and multivariable analyses via logistic regression were conducted for all independent variables to identify their relationship with malignancy. Applying receiver operating characteristic (ROC) curves and Youden's Index to significant variables, we attempted to identify optimal threshold values to predict malignancy of the soft tissue mass.

RESULTS

A total of 623 tumours and pseudo-tumours were analysed, and majority were benign (n = 605, 97.1%). The most common pseudo-tumour, benign, and malignant tumours were ganglion cysts (n = 289, 90.3%), plantar fibromas (n = 54, 18.9%) and pleomorphic undifferentiated sarcomas (n = 4, 22.2%), respectively. Increasing age (P = 0.036), larger size of mass (P < 0.001) and male gender (P = 0.017) were significant predictors of malignancy. ROC and Youden's Index analyses identified optimal threshold values of 4.0 cm (area under curve [AUC] = 87.6%) for size of mass and 66 years (AUC = 60.7%) for age.

CONCLUSION

Majority of foot and ankle soft tissue masses are benign. Increasing age, larger size of mass and male gender are significant predictors of malignancy. The threshold value in predicting malignancy is 4.0 cm for size of mass and 66 years for age.

Plasma Cell Dyscrasia of the Calcaneus: A Rare and Unusual Case Presentation

A rare and unusual case of plasma cell dyscrasia of the calcaneus is presented. Clinically, the patient had a draining and painful ulcer that was treated with appropriate antibiotics and wound care but failed to show any signs of healing. Radiographic images showed cystic changes of the calcaneus in the vicinity of the ulcer. Blood work was negative for bone and soft-tissue infection, but uric acid and alkaline phosphatase levels were elevated. Nuclear bone scan showed increased uptake in the calcaneus suggestive of osteomyelitis. One possible differential diagnosis was an intraosseous gouty tophus deposit. Not convinced that this was either a bone infection or gout, the author performed a bone biopsy. Pathologic evaluation indicated plasma cell dyscrasia. Continued wound care healed the ulcer completely, with resolution of pain of his heel. Oncology/hematology was consulted, and 16 months after biopsy, he remains asymptomatic.

Complications, mobility, and quality of life in ankle sarcoma patients

AIMS

The aims of the study were to analyze differences in surgical and oncological outcomes, as well as quality of life (QoL) and function in patients with ankle sarcomas undergoing three forms of surgical treatment, minor or major limb salvage surgery (LSS), or amputation.

METHODS

A total of 69 patients with ankle sarcomas, treated between 1981 and 2017 at two tumour centres, were retrospectively reviewed (mean age at surgery: 46.3 years (SD 22.0); 31 females (45%)). Among these 69 patients 25 were analyzed prospectively (mean age at latest follow-up: 61.2 years (SD 20.7); 11 females (44%)), and assessed for mobility using the Prosthetic Limb Users Survey of Mobility (PLUS-M; for amputees only), the Toronto Extremity Salvage Score (TESS), and the University of California, Los Angeles (UCLA) Activity Score. Individual QoL was evaluated in these 25 patients using the five-level EuroQol five-dimension (EQ-5D-5L) and Fragebogen zur Lebenszufriedenheit/Questions on Life Satisfaction (FLZ).

RESULTS

Of the total number of patients in the study, 22 (32%) underwent minor LSS and 22 (32%) underwent major LSS; 25 underwent primary amputation (36%). Complications developed in 26 (38%) patients, and were more common in those with major or minor LSS in comparison to amputation (59% vs 36% vs 20%; p = 0.022). A time-dependent trend towards higher complication risk following any LSS was present (relative risk: 0.204; 95% confidence interval (CI) 0.026 to 1.614; p = 0.095). In the prospective cohort, mean TESS was higher following minor LSS in comparison to amputation (91.0 vs 67.3; p = 0.006), while there was no statistically significant difference between major LSS and amputation (81.6 vs 67.3; p = 0.099). There was no difference in mean UCLA (p = 0.334) between the three groups (p = 0.334). None of the items in FLZ or EQ-5D-5L were different between the three groups (all p > 0.05), except for FLZ item "self-relation", being lower in amputees.

CONCLUSION

Complications are common following LSS for ankle sarcomas. QoL is comparable between patients with LSS or amputation, despite better mobility scores for patients following minor LSS. We conclude that these results allow a decision for amputation to be made more easily in patients particularly where the principles of oncological surgery would otherwise be at risk. Cite this article: Bone Joint J 2021;103-B(3):553-561.

Dorsal Medial Cuneiform Bony Outgrowth-Apophysis or Exostosis: A Case Report

CASE

Three female children (11-15 years) presented with painful dorsomedial medial cuneiform masses that did not improve after conservative treatment. Findings were consistent with a diagnosis of medial cuneiform apophysis. After surgical resection, no patients had recurrence, although one continued to have pain from a deep peroneal nerve sensory branch that was resected. One patient had an intramass physis identified.

CONCLUSION

When surgically removing dorsomedial cuneiform masses, surgeons should decompress overlying sensory nerve branches, detach and subsequently repair muscular attachments, and remove the entire stump to prevent regrowth because some of these masses may be apophyses and not exostoses.

Malignant tumours of the foot and ankle

Tumours of the foot and ankle constitute about 4-5% of all musculoskeletal tumours with the majority of them being benign. Diagnosis of malignant soft tissue or bone tumours is frequently delayed because of the relatively low prevalence and uncommon presentation at the foot and ankle. Suspicious lesions or lumps should be subjected to CT, MRI and biopsy. Subfascial location, lump size more than 5 cm, increase in size, painful and recurrent tumours should raise the suspicion of malignancy and lead to patient referral to a designated tumour centre. Neoadjuvant and adjuvant systemic chemotherapy and/or radiation therapy, isolated limb perfusion (ILP) and hyperthermia for malignant tumours have to be discussed in a multidisciplinary tumour board. With the advances in local and free tissue transfer, limb-sparing techniques have increasingly replaced primary amputations thus preserving lower limb function as much as possible without compromising on the principles of oncologic resection.

Functional and oncological outcomes of limb-salvage surgery for foot and ankle tumors

BACKGROUND

Limb-salvage surgery has become the backbone treatment for musculoskeletal tumors in the last decades. However, limb-salvage with safe margins for tumors of the foot and ankle is challenging, due to the complex anatomy of this region. This study aimed to evaluate functional and oncological outcomes, complications, and local recurrence of limb-salvage procedures for tumors of the foot and ankle.

METHODS

This study was a retrospective review of 18 patients with primary tumors of the foot and ankle who underwent limb-salvage surgery between 1996 and 2015, with a minimum follow-up of 2 years. Clinical presentations, radiological and histopathological investigations, surgical procedures, functional and oncological outcomes, complications and local recurrences were analyzed. The Musculoskeletal Tumor Society (MSTS) scoring system was utilized for evaluation of the functional outcome.

RESULTS

With a mean follow-up period of 44.2 months, 7 males and 11 females with a mean age of 29.2 years were included. Nine patients were presented as recurrent cases. The most common location was forefoot in 7 patients. Synovial sarcoma was the histopathologic diagnosis in 7 patients. The final surgical margins were wide in 15 patients, wide-contaminated in one patient, and marginal in two patients. After resection, soft tissue reconstruction and wound coverage were done by soft tissue flaps in 4 patients. The mean MSTS score was 27.5. Four patients developed local recurrence, all of them were recurrent cases.

CONCLUSION

Limb-salvage surgery for foot and ankle tumors is an effective treatment option with good functional outcome.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Clinical applications of allografts in foot and ankle surgery

PURPOSE

The purpose of this review is to systematically analyse current literature on the use of allografts in the surgical treatment of foot and ankle disorders in adult patients. Based on this study, we propose evidence-based recommendations.

METHODS

The database for PubMed was searched for all published articles. No timeframe restrictions were applied. Clinical studies eligible for inclusion met the following criteria: performed on patients over 18 years old; subject to surgical treatment of foot and ankle disorders; with report on the outcome of the use of allografts; with a report and assessment of pain and function, or equivalent; minimum follow-up of 1 year was required. Two reviewers independently screened and selected studies for full-text analysis from title and abstract. 107 studies were included from 1113 records. Studies were grouped according to surgical indications into ten categories: musculoskeletal tumours (n = 16), chronic ankle instability (n = 15), ankle arthritis (n = 14), osteochondral lesions of the talus (n = 12), Achilles tendon defects (n = 11), other tendon defects (n = 9), fusions (n = 9), fractures (n = 8), hallux rigidus (n = 3) and other indications (n = 10).

RESULTS

Most studies displayed evidence level of IV (n = 57) and V (n = 39). There was one level I, one level II and nine level III studies. Most studies reported allografting as a good option (n = 99; 92.5%). Overall complication rate was 17% (n = 202).

CONCLUSIONS

Fair evidence (Grade B) was found in favour of the use of allografts in lateral ankle ligament reconstruction or treatment of intra-articular calcaneal fracture. Fair evidence (Grade B) was found against the use of allogeneic MSCs in tibiotalar fusions.

LEVEL OF EVIDENCE

V.

Schwannoma of the foot: report of four cases and literature review

Schwannoma is a soft tissue tumor that rarely presents in the foot. Patients are usually asymptomatic, but in some cases symptoms typically result from the mass effect and direct involvement of the nerve and surrounding tissue. We report on four consecutive cases. The first patient was a 57-years-old female that referred symptoms similar to the Morton’s neuroma with a mass arising from the medial plantar nerve. The second patient was treated for a schwannoma in the plantar area. The third case was a female with a schwannoma arising from the sural nerve and the fourth patient had a tumor arising from the medial plantar nerve. All patients underwent surgical excision and histological evaluation. No signs of neurological deficit or recurrence were observed at final follow-up. Purpose of the study was to define clinical features, optimal management and outcome of schwannomas of the foot, through an accurate review of the literature. (www.actabiomedica.it)

Bone and Soft Tissue Tumors About the Foot and Ankle

The foot and ankle delicately balance the need for support of the weight of the human body, with the need for flexibility. Palpable masses about the foot and ankle, therefore, are most commonly related to trauma or mechanical instability. Non-neoplastic causes, such as ganglion cysts and callus, therefore, predominate. However, the radiologist must be aware of the imaging appearance of less common benign and malignant neoplasms that can involve the foot and ankle.

Synovial Sarcoma of the Digits: A Case Report of an Unplanned Excision

Synovial sarcoma is a rare occurrence in the lower extremity, although the presenting symptoms can mimic those of other more common and benign musculoskeletal pathologies. We present the case of a patient who was originally thought to have a Morton's neuroma or ganglionic cyst. The correct diagnosis, synovial sarcoma, was determined only after an unplanned excision. Despite the patient presenting with symptoms similar to those of a compressive neuropathy, a high index of suspicion should be present when a patient presents with any soft tissue mass, especially if it has an unusual clinical appearance to avoid an unplanned excision.

Osteochondroma of the Cuboid: A Case Report

Osteochondromas are common benign exostoses with <1% of pedal occurrences. Several cases of osteochondromas have been previously reported in the foot and ankle but none from the cuboid. In the present study, we report a case of osteochondroma originating from the cuboid in a 29-year-old male patient. The patient presented with an aching and shooting pain to his left foot that had progressed during the course of 3 years. Originally diagnosed as a fibroma, the patient had undergone cortisone injections that did not help with his symptoms. Radiographic and magnetic resonance imaging revealed an osteochondroma to the patient's left cuboid. Surgical removal of the tumor confirmed the diagnosis. The patient had an uneventful postoperative recovery and had no recurrence after 1.5 years of follow-up. In conclusion, although osteochondromas are rare in the foot and ankle and most are benign, they can result in many symptoms and can impair patients' quality of life, such as occurred in our patient. Recommendations for surgical excision should be determined on a case-by-case basis.

Distribution patterns of foot and ankle tumors: a university tumor institute experience

BACKGROUND

Bone and soft tissue masses of the foot and ankle are not particularly rare but true neoplasia has to be strictly differentiated from pseudotumorous lesions. Diagnosis is often delayed as diagnostic errors are more common than in other regions. Awareness for this localization of musculoskeletal tumors is not very high and neoplasia is often not considered. The purpose of this study is to provide detailed information on the incidence and distribution patterns of foot and ankle tumors of a university tumor institute and propose a simple definition to facilitate comparison of future investigations.

METHODS

As part of a retrospective, single-centre study, the data of patients that were treated for foot and ankle tumors between June 1997 and December 2015 in a musculoskeletal tumor centre were analyzed regarding epidemiologic information, entity and localization. Included were all cases with a true tumor of the foot and ankle. Exclusion criteria were incomplete information on the patient or entity (e.g. histopathological diagnosis) and all pseudotumoral lesions.

RESULTS

Out of 7487 musculoskeletal tumors, 413 cases (5,52%) of tumors of the foot and ankle in 409 patients were included (215 male and 198 female patients). The average age of the affected patients was 36 ± 18y (min.3y, max.92y). Two hundred sixty-six tumors involved the bone (64%), among them 231 (87%) benign and 35 (13%) malignant. There were 147 soft tissue tumors (36%), 104 (71%) were benign, 43 (29%) malignant. The most common benign osseous tumor lesions included simple bone cysts, enchondroma and osteochondroma. By far the most common malignant bone tumor was chondrosarcoma. Common benign soft tissue tumors included pigmented villo-nodular synovitis, superifcial fibromatosis and schwannoma whereas the most common malignant members were synovial sarcoma and myxofibrosarcoma. Regarding anatomical localization, the hindfoot was affected most often.

CONCLUSIONS

Knowledge of incidence and distribution patterns of foot and ankle tumors will help to correctly assess unclear masses and initiate the right steps in further diagnostics and treatment. Unawareness can lead to delayed diagnosis and inadequate treatment with serious consequences for the affected patient.

Primary Tumor and Tumor-Like Lesions of Bones of the Foot: Single-Center Experience of 166 Cases

Primary bone tumors of the foot are rare lesions. The purpose of the present study was to evaluate the clinical manifestations, treatment modalities, and recurrences of various primary bone tumors of the foot from a specialized center for orthopedic oncology. Among 3681 musculoskeletal tumor cases, which were diagnosed and surgically treated in our hospital from 1983 to 2013, 166 primary tumor and tumor-like bone lesions of the foot (4.5%) were retrospectively reviewed regarding age, gender, localization, biopsy-revealed diagnosis, applied treatment modalities, follow-up period, and recurrence, if any. Of the 166 primary bone tumors of the foot, 155 (93.4%) were benign and 11 (6.6%) were malignant. The most common primary benign bone tumor was a unicameral bone cyst (57 of 155; 36.8%), and the most common malignant tumor was chondrosarcoma (7 of 11; 63.6%). The hindfoot was the most common location for both primary benign (104 of 155; 67.1%) and malignant (6 of 11; 54.5%) bone tumors of the foot. The results of our study have confirmed that the radiologic findings can be confusing owing to the structural and histopathologic features of the bones of the foot; thus, histopathologic diagnosis should be considered for foot involvement. Because the characteristics of the compartments in the foot allow for the rapid spread of malignant lesions, aggressive surgical management and wider resection are recommended to prevent recurrence and further spread.

High-Grade Osteosarcoma of the Foot: Presentation, Treatment, Prognostic Factors, and Outcome of 23 Cooperative Osteosarcoma Study Group COSS Patients

Osteosarcoma of the foot is a very rare presentation of a rare tumor entity. In a retrospective analysis, we investigated tumor- and treatment-related variables and outcome of patients registered in the Cooperative Osteosarcoma Study Group (COSS) database between January 1980 and April 2016 who suffered from primary high-grade osteosarcoma of the foot. Among the 23 eligible patients, median age was 32 years (range: 6–58 years), 10 were female, and 13 were male. The tarsus was the most commonly affected site (n=16). Three patients had primary metastases. All patients were operated: 5 underwent primary surgery and 18 received surgery following preoperative chemotherapy. In 21 of the 23 patients, complete surgical remission was achieved. In 4 of 17 patients, a poor response to neoadjuvant chemotherapy was observed in the resected primary tumors. Median follow-up was 4.2 years (range: 0.4–18.5). At the last follow-up, 15 of the 23 patients were alive and 8 had died. Five-year overall and event-free survival estimates were 64% (standard error (SE) 12%) and 54% (SE 13%), which is similar to that observed for osteosarcoma in general. Event-free and overall survival correlated with primary metastatic status and completeness of surgery. Our findings show that high-grade osteosarcoma in the foot has a similar outcome as osteosarcoma of other sites.

Total calcanectomy for metastasis of renal cell carcinoma in the calcaneus: A case report

We present a rare case of metastasis of renal cell carcinoma to the calcaneus in a 59-year-old man who presented with pain and inability to bear weight on the left foot 3 years after right nephrectomy for renal cell carcinoma. He successfully underwent en bloc resection of his right calcaneus with a limb salvage procedure, total calcanectomy without bony reconstruction. Histological findings identified the lesion as a metastasis originating from a renal cell carcinoma. Recent follow-up examination showed no recurrence. To the best of our knowledge, this is the first reported case to be treated with total calcanectomy for renal cell carcinoma metastasis.

Underlying Adenocarcinoma of the Lung Metastasizing to the Proximal Phalanx of the Foot Causing Complex Regional Pain SyndromeA Case Report

We report an unusual case of adenocarcinoma of the lung metastasizing to the proximal phalanx of the third digit in a 56-year-old woman with overlying complex regional pain syndrome. The patient was initially treated for neuroma, fracture, and neuropathic pain with no improvement over a 4-month period before presenting to the emergency department for left third digit pain. Radiographic imaging showed substantial osteopenia and mottling; magnetic resonance imaging demonstrated an aggressive lesion to the proximal phalanx. The patient underwent excision of the lesion, revealing metastatic moderately differentiated adenocarcinoma.

Assessment of the Pediatric Foot Mass

Masses in the pediatric foot are relatively uncommon and can present a diagnostic challenge. The literature lacks a comprehensive overview of these types of lesions. Most are benign soft-tissue lesions that can be diagnosed on the basis of history and physical examination. However, some rare malignant neoplasms can mimic benign masses. It is imperative to recognize these lesions because the consequences of a delayed or missed diagnosis can be substantial. A thorough history and physical examination of all pediatric patients with foot lesions are crucial to ensure that any lesion not readily identified as benign is appropriately managed.

Acrometastasis following colorectal cancer: A case report and review of literature

INTRODUCTION

Colorectal cancer commonly metastasises to the liver, peritoneum and lungs. Bony metastases are uncommon in colorectal cancer and in particular metastases to the hands or feet (acrometastasis) are an extremely rare occurrence.

CASE PRESENTATION

A 65-year-old male with a colonic malignancy underwent elective anterior resection. Intra-operatively he was found to have a pelvic collection necessitating an end colostomy. Histology confirmed complete Dukes B tumour excision with no evidence of lymph node metastases. The patient underwent chemo-radiotherapy but was unsuitable for reversal of Hartmann's due to elevated CEA levels and asymmetrical thickening of the rectal stump with a solitary lung nodule identified at a one-year surveillance CT. The lung nodule was resected revealing metastatic adenocarcinoma and biopsies from the rectal stump showed chronic inflammatory changes. The patient was offered further chemotherapy. However, six years after his original surgery the patient presented with an acutely painful left foot with radiographic appearances of an infiltrative sclerotic and lucent lesion confirmed as a calcaneal acrometastasis on Magnetic Resonance Imaging (MRI).

DISCUSSION

Diagnosis of acrometastasis is challenging and generally constitutes a wider metastatic process with poor prognosis. Patients are often asymptomatic or present with symptoms mimicking benign lesions such as arthritis, infection or ligamentous sprains of the hands or feet. Therefore, there should be a high index of suspicion and prompt radiological investigation is warranted in order to exclude disease recurrence.

CONCLUSION

Although acrometastasis may indicate a poor prognosis, timely diagnosis and intervention may facilitate improvement of long-term survival and symptomatic management.

Structural allograft reconstruction of the foot and ankle after tumor resections

BACKGROUND

Structural allografts have been used to correct deformities or to fill bone defects secondary to tumor excisions, trauma, osteochondral lesions, or intercalary arthrodesis. However, the quality of published evidence supporting the use of allograft transplantation in foot and ankle surgery has been reported as fair. The purpose of this study was to report the overall survival of structural allograft in the foot and ankle after tumor resection, and the survival according to the type of allograft and the complication rates in the medium to long term.

MATERIALS AND METHODS

From January 1989 to June 2011, 44 structural allograft reconstructions of the foot and ankle were performed in 42 patients (28 men and 14 women) due to musculoskeletal tumor resections. Mean age at presentation was 27 years. Mean follow-up was 53 months. Demographic data, diagnosis, site of the neoplasm, operations performed, operative complications, outcomes after surgery, date of last follow-up evaluation, and local recurrences were reviewed for all patients. Regarding the type of 44 allograft reconstructions, 16 were hemicylindrical allografts (HA), 12 intercalary allografts (IA), 10 osteoarticular allografts (OA), and 6 were total calcaneal allograft (CA).

RESULTS

The overall allograft survival rate, as calculated with the Kaplan-Meier method, at 5 and 10 years was 79 % (95 % CI 64-93 %). When allocated by type of allograft reconstruction the specific allograft survival at 5 and 10 years was: 83 % for CA, 80 % for HA, 77 % for OA, and 75 % for IA. The complications rate for this series was 36 % including: articular failure, local recurrence, infection, fracture and nonunion.

CONCLUSION

This study showed that structural allograft reconstruction in the foot and ankle after tumor resection may be durable with a 79 % survival rate at 5 and 10 years. The two types of allografts that showed better survival rate were hemicylindrical allografts (80 %) and calcaneus allografts (83 %). The highest complication rates occurred after calcaneus allografts and osteoarticular allografts.

LEVEL OF EVIDENCE

IV.

Synchronous phalangeal metastases in upper and lower limbs from primary breast malignancy: a rare case scenario with a review of the literature

Osseous metastasis from a primary breast cancer is common, and the skeletal related morbidity is high. However, solitary acral bony metastasis is rare and the diagnosis of these lesions poses a challenge to the physician. We describe a case of a patient treated with primary breast cancer who later presented with metastatic osteolytic bone lesions confined to a forefinger and toe.

Osteosarcoma of the Foot

A 40-year-old man presented with a large and painful right foot mass. The patient reported a history of a recurrent right foot mass treated elsewhere with 3 prior surgical excisions.

Osteochondroma of the Talar Neck: A Case Report and Literature Review

Osteochondroma occurs most frequently in the long bones such as the proximal humerus, tibia, and distal femur. It is rare for it to originate in the talar neck. In the present case report, we describe a case of osteochondroma arising from the talar neck. Furthermore, a review of the published studies of talar osteochondroma was performed to obtain a better understanding of the symptoms, diagnosis, and treatment of this unusual entity.

Reconstruction of bilateral tendoachilles with fascia lata graft

A 19 year old male presented with progressive enlargement of both tendoachilles for 2 years and difficulty in walking for 3 months. The neurological history and examination revealed progressive mental deterioration and ataxia. The blood investigation revealed hypercholesterolemia. We report this rare case of cerebrotendinous xanthomatosis with bilateral tendoachilles enlargement, which was treated by excision of bilateral tendoachilles and reconstruction with fascia lata. The American Orthopedic Foot and Ankle Society hindfoot score was 93/100 bilaterally and the subjective evaluation of the patient showed very good results.

Verrucous carcinoma of the foot with bone invasion: a case report

Verrucous carcinoma of the foot often affects deep structures such as tendons, muscles, or bones. A 74-year-old man presented with a foot lesion that had been diagnosed as a skin infection 7 years earlier. He was treated with multiple excisions and superficial biopsies associated with antibiotic therapy without success. In our department he underwent an aggressive and accurate debridement with marginal excision harvesting multiple biopsies. Pathological evaluation of tissue at the time of operation confirmed the diagnosis of verrucous carcinoma of the foot. Therefore, the patient underwent an amputation below knee, and there were no postoperative complications; the patient was able to walk with the aid of a prosthesis with no signs of recurrence. The lesion follows a chronic course evolving from a discrete focal lesion to a large fungating deeply penetrating mass often compromised by local infection. The slow growth and confusing early-stage appearances can lead to delays in diagnosis of 8 to 15 years causing the extracutaneous involvement that requires a leg amputation. Many patients are initially treated with many topical medications without success, and most tumors have been treated as recalcitrant warts or corns for some time, whereas the basic approach is surgical.

Do malignant bone tumors of the foot have a different biological behavior than sarcomas at other skeletal sites?

We analyze the delay in diagnosis and tumor size of malignant bone tumors of the foot in a retrospective study. We compared the oncological and surgical long-term results with identical tumor at other anatomical sites in order to analyze the biological behavior of sarcomas that are found in the foot. Thirty-two patients with a histologically proven malignant bone tumor (fifteen chondrosarcomas, nine osteosarcomas, and eight Ewing sarcomas) between the years 1969 and 2008 were included. The median follow-up was 11.9 years. The overall median time gap between the beginning of symptoms and diagnosis in the study group was 10 months. Ewing sarcoma presented with the longest delay in diagnosis (median of 18 months), followed by osteosarcoma (median of 15 months) and chondrosarcoma (median of 7.5 months). The delay in diagnosis of these tumors was significantly longer than that of equivalent tumors at other skeletal sites, but the 5- and 10-year survival rates and the occurrence of distant metastases were comparable. In contrast, the average size of foot tumors was 5- to 30-fold less than that of tumors analyzed at other skeletal sites. This study indicates that sarcomas of the foot demonstrate a distinct biological behavior compared to the same tumor types at other skeletal sites.

Giant osteochondroma of the talar neck

Giant osteochondroma is an uncommon entity and it is rare in the foot and ankle region. It is extremely rare to originate from the talus. In this case report we present a case of giant osteochondroma arising from the talar neck measuring 100 mm × 90 mm × 30 mm. It is unique because of the size, site and the age at presentation.

[Tumors of the foot: diagnostics and therapy]

Despite the compact anatomy with thin soft tissue coverage, diagnosis of both benign and malignant tumors of the foot is often delayed. Diagnostic errors are more common than in other body regions, as neoplasias are rarely considered. Barring a few exceptions the foot is not a typical predilection site for malignant musculoskeletal tumors, although, basically any tumor entity of the musculoskeletal system can affect the foot. Delays in specific diagnostic and therapeutic procedures of these lesions can entail serious consequences for patients as tumor size is a major prognostic factor for recurrence-free survival. In cases of an indistinct persistent swelling or bone lesion a tumorous process should always be considered to ensure early diagnosis and therapy of foot tumors.

Bilateral Achilles tendon enlargement

Cerebrotendinous xanthomatosis is a rare, autosomal-recessive, lipid-storage disease with accumulation of cholestanol in most tissues, particularly within the Achilles tendons. It has been characterized both clinically and biochemically, and recently from the molecular biological aspect as well. Juvenile cataract, childhood diarrhea, mental retardation, cerebellar ataxia, and tendon xanthomas are the most prominent features of this disease. Bilateral symmetrical firm masses of Achilles tendons may be the first symptom the patient recognizes because it can jeopardize his or her ability to walk. However, the treatment strategies for tendon tumors vary. In a recent case, we diagnosed the disease properly, according to the clinical manifestations and the radiological and laboratory examinations. The genetic mutation was characterized by analyzing sterol 27-hydroxylase from the patient's family (located on nucleotide 599) and led to a nonsense mutation. It is a unique type of mutation that has never been reported to our knowledge. Tendon lesions are characterized by the loss of muscle fibers and accumulation of lipid products. To help the patient regain the strength of the Achilles tendon and walking abilities, a large area of tendon tumor was excised, followed by reconstruction with a tibialis posterior allograft, which is the second strongest tendon in the foot and ankle. Although the use of this type of graft is uncommon, the final result was satisfactory. At the 10-month follow-up examination, the patient could walk easily without pain. This case report suggests that the surgical procedure will provide an alternative for the repair of large-area degenerative Achilles tendons.

The adverse effect of an unplanned surgical excision of foot soft tissue sarcoma

Background

Malignant soft tissue tumors of the foot are extremely rare and thus can be prematurely excised without appropriate preoperative evaluation. The present study compares adverse effects between unplanned and planned surgical excisions.

Methods

We retrospectively reviewed the clinical records, radiographs, pathology reports and pathological specimens of 14 consecutive patients with soft tissue sarcoma of the foot among 592 with sarcomas between 1973 and 2009. We then compared the incidence and clinical outcomes after unplanned (UT; n = 5) and planned (PT; n = 9) surgical excisions of foot sarcomas.

Results

The most frequent diagnosis was synovial sarcoma (n = 4; 28.6%). The overall 5-year survival rates of the PT and UT groups were 65.6% and 60.0%, respectively, and the event-free 5-year survival rates were 63.5% and 40.0%, respectively. Event-free and overall survival rates did not significantly differ between the two groups. However, tumors were significantly larger in the PT group than in the UT group (p < 0.05).

Conclusions

Unplanned resection lead to a relatively worse prognosis and a likelihood of recurrence despite additional resections. We recommend that soft tumors of the foot should only be excised after appropriate preoperative evaluation regardless of the size of the tumor.

Osteosarcoma: A rare cause of painful enlargement of the hallux

Malignant osseous and soft-tissue tumors of the foot are rare. We report a case of osteosarcoma in the proximal phalanx of the hallux in a 45-year-old man. In patients with foot-related symptoms, a high index of suspicion for pedal osteosarcoma is required. Delayed or inappropriate diagnosis may compromise limb-sparing surgery and survivorship.

Solitary navicular metastasis of a pulmonary adenocarcinoma

The authors present a case of a 62-year-old male with a symptomatic isolated midfoot metastasis as the first clinical presentation of a primary pulmonary tumor. In this case of a metastatic adenocarcinoma, the lesion leading to diagnosis was located in the foot. The poor outcome and the sparse relevant literature are presented in brief.

LEVEL OF EVIDENCE

Therapeutic, Level IV.

Peripheral nerve sheath tumors of the foot and ankle

BACKGROUND

Peripheral nerve sheath tumors (PNSTs) are soft tissue neoplasms found in intimate association with a peripheral nerve. They are rarely seen in the foot and ankle where they have an innocuous appearance, but these tumors have the potential to become malignant. This study reports a large series of foot and ankle PNSTs surgically treated at a single institution.

MATERIALS AND METHODS

Retrospectively, all cases of PNSTs confirmed by biopsy and surgically treated from 1992 to 2008 were included in the study. Preoperative, perioperative and postoperative variables were collected. Foot and ankle tumors were compared with the overall group of PNSTs. Fisher's test and Student's t-test were implemented to address the significance of the findings (p ≤ 0.05).

RESULTS

From all PNSTs identified (n = 137), there were 14 (10.2%) foot and ankle. A painful mass was the most common presenting symptom. Schwannoma represented the most common histologic type. Two cases of malignant foot and ankle PNSTs were identified. Foot and ankle PNSTs were significantly smaller in size and showed fewer postoperative neurologic deficits than the overall group of PNSTs. No differences were found in terms of histologic type distribution, age at diagnosis, duration of symptoms and postoperative tumor recurrence, but there was a preponderance of females in this series of foot and ankle tumors.

CONCLUSION

PNSTs of the foot and ankle usually present as innocuous, slow-growing masses leading to misdiagnosis and suboptimal surgical treatment of a potentially malignant lesion. A comprehensive diagnostic evaluation, preoperative planning and meticulous surgical excision are required to prevent tumor recurrence and minimize the incidence of postoperative sequelae, thus improving postoperative functional outcomes.