The differential diagnosis of foot lumps: 101 cases treated surgically in North Glasgow over 4 years

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.

Benign soft tissue tumours of the foot & ankle: A pictorial review

The purpose of this pictorial review is to aid the clinician in distinguishing different benign lesions within the foot and ankle. We discuss the typical clinical and radiological findings as well as management options for intra and extra-compartmental lesions. Differentiation between sarcoma and benign lesions is imperative when presented with any mass in the foot or ankle.

Phosphaturic Mesenchymal Tumor of the Ankle: A Case Report and Review of the Literature

We report the case of a phosphaturic mesenchymal tumor of the ankle; an extremely rare lesion that causes osteomalacia via paraneoplastic renal phosphate wasting. A 41-year-old man was referred to plastic surgery with a swelling over the anterior ankle, which had been increasing in size for 1 year. Focused ultrasound assessment was inconclusive, but excision biopsy demonstrated features in keeping with a phosphaturic mesenchymal tumor. Evidence of tumor-induced osteomalacia was subsequently identified on review of historical biochemistry. The patient was followed-up for 1 year with normalization of serum phosphate. In this case report, we present a discussion of the differential diagnosis for foot and ankle soft tissue lesions, and a review of the literature regarding the diagnosis and management of these tumors. Accurate identification of any soft tissue lesion on clinical examination alone is extremely challenging and excision biopsy should be considered in cases of diagnostic uncertainty.

Giant cell tumour of EHL tendon sheath in young: a rare case report and review of the literature

Giant cell tumour of tendon sheath also known as benign synovioma is a slow-growing benign tumour originating from tendon sheath, ligaments or bursa. We present a case of swelling over the left foot of 7-month duration in 11-year-old boy diagnosed as giant cell tumour of tendon sheath. There was an extensive pressure effect of tumour mass on the second metatarsal evident by scalloping. Local excision was planned and executed, and reduction in scalloping was evident at 26-month follow-up with no recurrence. We conclude that en bloc resection of tumour with a hydrogen peroxide lavage may result in a favourable prognosis without recurrence.

Hemorrhagic Synovitis of the First Metatarsophalangeal Joint: A Case Report

CASE

A 69-year-old woman presented with a painful mass at her first metatarsophalangeal joint. Further evaluation was concerning for a neoplastic process, leading to surgical intervention. Pathological examination demonstrated hemosiderotic synovitis, and hematologic evaluation led to a new diagnosis of von Willebrand disease.

CONCLUSION

Hemorrhagic synovitis, involving mostly larger joints, has been well described. However, a literature search demonstrates no cases of this in the foot or toes. Presentation of hemarthroses and underlying coagulopathies can be subtle and must be considered in patients presenting with soft-tissue masses or pseudotumors, despite having no previous diagnosis.

Rare Case of a Very Large Angioleiomyoma of the Dorsum Foot

Angioleiomyomas are relatively rare benign smooth muscle soft tissue tumors which often occur on the extremities. They are rarely diagnosed preoperatively as clinical and radiological examination is often nonspecific and inconclusive. An 80-year-old male presented with a 10-year history of a progressively growing and symptomatic lesion on his right dorsal foot within the first intermetatarsal space. The preoperative diagnosis was suspected to be a neurogenic schwannoma arising from the deep peroneal nerve. Simple excision and histopathology confirmed a diagnosis of angioleiomyoma with nil recurrence or complications. The size of the angioleiomyoma was the second largest reported in literature to date. Angioleiomyomas are often misdiagnosed, and a degree of suspicion should be maintained in patients presenting with lower extremity growing soft tissue tumors.

Benign Schwannoma of the Lateral Plantar Nerve: A Case Report

Schwannomas are benign, encapsulated soft-tissue tumors that rarely present to the foot and ankle. These tumors are usually asymptomatic unless an increase in size or disruption of the nerve causes pain. We report a case of a painful mass along the lateral plantar nerve near the fourth metatarsal base that was surgically excised and confirmed as a benign schwannoma by means of histopathologic analysis. At the final follow-up of over 2 years, the patient reported no pain, neurologic deficits, or signs of recurrence. This case demonstrates an unusual location of a schwannoma arising from the lateral plantar nerve.

Intramuscular Ganglion Cyst of the Flexor Hallucis Brevis Secondary to Muscle Tear: A Case Report

In the current study, we present a case of an intramuscular ganglion cyst in the flexor hallucis brevis muscle (FHB) that arose secondary to a muscle tear. Through this study, we propose a possible aetiology for the development of intramuscular ganglionic cysts. A 50-year-old woman presented with acute pain and swelling over the right mid-plantar area after prolonged kneeling for scrubbing floors. Ultrasonography examination performed at 5 days after the onset of symptoms revealed a partial tear of the right FHB. Follow-up evaluations were conducted, with magnetic resonance imaging and ultrasonography, at 24 and 54 days after symptom onset. MRI revealed a ganglion cyst in the mid-portion of the FHB without connection to the adjacent joint capsule or tendon sheath. On the ultrasonography examination at 45 days after onset, at the same location where a tear was seen on the initial examination, an anechoic defect in the mid-portion of the FHB was observed, compatible with a ganglion cyst. Given the favourable natural evolution, no aspiration or surgery were performed. The patient was discharged with minimal symptoms. The results suggest that the intramuscular ganglion cyst can develop following a muscle tear.

Ultrasound as a diagnostic and interventional aid at point-of-care in dermatology clinic: a case report

Ultrasound is currently underutilized in dermatology practice. However, ultrasound provides clinicians with precise and unique information on cutaneous and subcutaneous lesions, while minimizing costs and complications related to more common and invasive diagnostic methods. We report a patient who presented with a tender subcutaneous mass that was diagnosed and treated using point-of-care ultrasound-guidance at the dermatology clinic. Ultrasound revealed features consistent with a ganglion cyst, which was subsequently injected with triamcinolone acetonide under ultrasound-guidance with the resolution of symptoms upon follow-up one month later. Our study demonstrates the utility of ultrasound as an effective, time-efficient diagnostic and interventional aid that can modify dermatology practice.

Salvage of the Foot for Recurrent Malignant Peripheral Nerve Sheath Tumor

Malignant peripheral nerve sheath tumors are rare soft tissue tumors accounting for 3% to 10% of all soft tissue tumors. They are strongly related to neurofibromatosis type 1, an autosomal dominant disease, and are characterized by aggressive biologic behavior, high local recurrence rates, and frequent metastases. Although the major nerves of the lower extremities are a common location of these tumors, scarce cases have been reported of malignant peripheral nerve sheath tumors involving the interdigital nerves of the foot. We report the case of a patient with non-neurofibromatosis type 1 and a recurrent malignant peripheral nerve sheath tumor of the first interdigital nerve of the foot treated successfully with limb salvage surgery with wide resection margins and reconstruction with an autogenous fibula graft.

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.

Origin of Satellite Ganglion Cysts with Effusion in the Flexor Hallucis Longus Tendon Sheath around the Hallux

Background

To describe the clinical and magnetic resonance imaging findings of ganglion cysts with effusion in the flexor hallucis longus tendon sheath around the hallux to evaluate their origin.

Methods

Patients with recurrent or painful ganglion cysts around the hallux with effusion in the flexor hallucis longus tendon sheath who underwent surgical treatment at St. Vincent's Hospital from February 2007 to August 2016 were investigated. Surgical indication was a painful or recurrent mass caused by the cystic lesions. Those without effusion of the flexor hallucis longus tendon sheath were excluded. We assessed the clinical and magnetic resonance imaging findings.

Results

Magnetic resonance imaging findings in all patients showed several ganglion cysts around the hallux and large fluid accumulations within the flexor hallucis longus tendon sheath. Regarding the location, six ganglion cysts were on the dorsomedial aspect, one on the plantar medial aspect, seven on the plantar lateral aspect, and one in the toe pulp. Ten patients showed joint effusions in both the metatarsophalangeal and interphalangeal joints, two in the metatarsophalangeal joints, and three in the interphalangeal joints. There were communication stalks with a tail shape or abutment between ganglion cysts with surrounding joint effusions. Intraoperatively, connections between ganglion cysts, the synovial cyst of the flexor hallucis longus tendon sheath, and surrounding joints were seen.

Conclusions

Synovial fluid accumulation in the metatarsophalangeal or interphalangeal joint supplies the synovial cyst of the flexor hallucis longus tendon sheath and subsequently ganglion cysts in the hallux. In clinical practice, the surgeon should carefully check surrounding joints with tendon sheaths to prevent recurrence of the ganglion cysts around the hallux.

Persistent Symptoms of Ganglion Cysts in the Dorsal Foot

Background

A ganglion is a common benign cystic lesion, containing gelatinous material. Ganglia are most commonly asymptomatic, except for a lump, but symptoms depend on the location. A dorsal foot ganglion is typically painful. On the dorsal foot, the dorsalis pedis artery and the medial branch of the deep peroneal nerve are located under the fascia.

Objective

Five female patients of average age 45.8 ± 20 years (range, 12 to 60 years) with a painful ganglion in the dorsal foot were analyzed.

Results

Average lesion size was 2.94 ± 1.1 cm (range, 1.5 to 4.0 cm) and patients had experienced pain for a median of 2-3 years (range, 6 months to 3 years). Four patients had a single cystic lesion and 1 patient had developed multiple cystic lesions over the time that were associated with hypoesthesia. In 3 cases, symptomatic lesions were located deep beneath the fascia and were resected. In 2 cases, the depth of the non-resected lesions was shallow.

Conclusion

The cause of a painful dorsal foot ganglion can be attributed to its location in the thin subcutaneous tissue over the foot bone, in addition to its proximity to a nearby artery and nerve. Mild symptoms caused by a dorsal foot ganglion seem to be persistent, and the deeper the location, the more likely is the need for resection. To avoid nerve injury, anatomical knowledge is prerequisite to any puncturing procedure or operation performed.

Ganglion cyst of the wrist treated with electroacupuncture: a case report

OBJECTIVE

To illustrate the clinical management of a ganglion cyst presenting on the right dorsal wrist.

CLINICAL FEATURES

A 38-year-old female complaining of a symptomatic right dorsal wrist ganglion of four years duration.

INTERVENTION AND OUTCOME

The patient was treated with high-frequency electroacupuncture in six consecutive treatments over a four week period and reported symptomatic improvement and a decrease in the size of the cyst following therapeutic intervention.

CONCLUSION

Ganglion cysts of the wrist are rather common benign connective tissue masses with variable treatment interventions. Electroacupuncture may be a novel and non-invasive conservative approach for the treatment of ganglion cysts. Further evaluation of the efficacy is warranted.

Solitary massive lipoma in the planter aspect of great toe presenting as two masses

Lipoma is rare in the planter aspect of the toes, and only few cases of massive lipoma have been reported in this site. The differential diagnosis of masses in the foot and toes is wide, and clinical diagnosis may be challenging. Access to magnetic resonance imaging, a standard diagnostic investigation for such soft tissue masses of the foot and toes, may be limited in some practice, requiring a reliance on clinical signs. We report a solitary massive lipoma in the planter aspect of the right great toe that appeared as two masses and with modification of typical clinical signs of lipoma.

Pitfalls in the cytological diagnosis of tenosynovial giant cell tumor: An illustration of eight discordant cases

Tenosynovial giant cell tumor (TSGCT) is a highly recurrent benign tumor of the extremities. Wide local excision is usually sufficient to achieve its recurrence-free outcome. However, that needs a confident pre-operative cytological diagnosis as TSGCT. Aspirates from this tumor express the characteristic polymorphic cytological pattern, enough to impose a definite diagnosis. However rarely so, inadequate sampling from smaller tumors or due to faulty techniques, and selective sampling from topographic clusters of any individual component may lead to wrong interpretation. An unorthodox location near the larger limb joints further complicates the diagnostic misery on occasions. Such tumors are amenable to incomplete removal and risk for future recurrence. In this report, we describe eight cases of TSGCTs that were cytologically diagnosed otherwise. The cytological features of these discrepant tumors and the factors attributable to such dilemma are elaborated. Finally, a possible remedy has been proposed at conclusion in order to avoid future inconveniences.

Malignant tumours of the foot and ankle

Most of tumours of the foot are tumour-like (synovial cyst, foreign body reactions and epidermal inclusion cyst) or benign conditions (tenosynovial giant cells tumours, planta fibromatosis). Malignant tumours of the soft-tissue and skeleton are very rare in the foot and their diagnosis is often delayed with referral to specialised teams after initial inappropriate procedures or unplanned excisions. The adverse effect of these misdiagnosed tumours is the increasing rate of amputation or local recurrences in the involved patients. In every lump, imaging should be discussed before any local treatment. Every lesion which is not an obvious synovial cyst or plantar fibromatosis should have a biopsy performed.

After the age of 40 years, chondrosarcoma is the most usual malignant tumour of the foot. In young patients bone tumours such as osteosarcoma or Ewing’s sarcoma, are very unusually located in the foot. Synovial sarcoma is the most frequent histological diagnosis in soft tissues. Epithelioid sarcoma or clear cell sarcoma, involve more frequently the foot and ankle than other sites. The classic local treatment of malignant conditions of the foot and ankle was below-knee amputation at different levels. Nowadays, with the development of adjuvant therapies, some patients may benefit from conservative surgery or partial amputation after multidisciplinary team discussions.

The prognosis of foot malignancy is not different from that at other locations, except perhaps in chondrosarcoma, which seems to be less aggressive in the foot. The anatomy of the foot is very complex with many bony and soft tissue structures in a relatively small space making large resections and conservative treatments difficult to achieve.

Cite this article: EFORT Open Rev 2017;2. DOI: 10.1302/2058-5241.2.160078. Originally published online at www.efortopenreviews.org

Intratendinous ganglion cyst of the extensor digitorum longus tendon: A case report

INTRODUCTION

Ganglion cysts are benign lesions, common in the hand and wrist. Intratendinous ganglion, however, are rare. We present the first reported case of an intratendinous ganglion cyst in an extensor digitorum longus (EDL) tendon of the foot.

CASE REPORT

A 35-year old presented with a left-sided painful dorsolateral foot swelling. Ultrasound suggested a ganglion cyst in proximity to the EDL tendon of the 5th toe. Two distinct swellings were identified on surgical exploration, including a 6×1cm ganglion lying within the EDL tendon substance that had resulted in tendon splitting. The lesions were excised and EDL tendon repaired. Histological analysis confirmed that both lesions were ganglion cysts. Post-operative recovery was uneventful.

DISCUSSION

Intratendinous ganglion cysts are rare lesions that pose a unique set of diagnostic and treatment challenges. Unlike conventional ganglion, their diagnosis may not be possible until surgical exploration. They have been reported to increase the risk of spontaneous tendon rupture. As such, a lower operative threshold should be applied to prevent their progression. A high index of suspicion should be applied to any ganglion reported radiologically to be in close contact with tendons. If diagnosed upon surgical exploration, it is essential that the operating surgeon is prepared to appropriately modify the procedure to involve primary tendon repair, tendon transfer or tenodesis.

Arthroscopic ganglionectomy of the foot and ankle

PURPOSE

To study the efficacy of arthroscopic ganglionectomy in the management of ganglia of the foot and ankle.

METHODS

From 2006 to 2010, arthroscopic ganglionectomy was performed for 89 ganglia in the foot and ankle of 88 patients. Clinical and intra-operative details were reviewed retrospectively.

RESULT

Ganglion stalk was identified in 6 % of the cases. The overall rate of presence of pathology was 26 %. The overall rate of recurrence or residual lesion was 12 % with high recurrent rate for extensor tendon ganglia and toe pulp ganglia.

CONCLUSIONS

Arthroscopic ganglionectomy of the foot and ankle ganglion by either internal drainage or complete resection is a feasible approach. Good results can be achieved in case of adequate internal drainage of the ganglion to the joints or fibrous tendon sheath.

Ganglion cyst of the foot treated with electroacupuncture: A case report

OBJECTIVE

To present the clinical management of a ganglion cyst presenting on the dorsolateral aspect of the foot.

CLINICAL FEATURES

A 45-year-old female cyclist complaining of ganglion cyst following training period.

INTERVENTION AND OUTCOME

Patient was treated with high-frequency electroacupuncture in four consecutive sessions over four weeks, and reported resolution of the cyst following therapeutic intervention.

CONCLUSIONS

Ganglion cysts of the foot are relatively rare connective tissue tumours with variable treatment approaches. Electroacupuncture may be a novel and non-invasive conservative approach for the treatment of ganglion cysts. Further evaluation of the efficacy of such treatment is warranted.

Ganglion cysts in the paediatric wrist: magnetic resonance imaging findings

BACKGROUND

The majority of published literature on ganglion cysts in children has been from a surgical perspective, with no dedicated radiologic study yet performed.

OBJECTIVE

Our aim was to assess the magnetic resonance (MR) imaging appearance of ganglion cysts in a series of paediatric MR wrist examinations.

MATERIALS AND METHODS

Ninety-seven consecutive paediatric MR wrist examinations were retrospectively reviewed for the presence of ganglion cysts. Only those studies with wrist ganglia were included. Cysts were assessed for location, size, internal characteristics and secondary effect(s).

RESULTS

Forty-one ganglion cysts (2-32 mm in size) were seen in 35/97 (36%) patients (24 female, 11 male), mean age: 13 years 11 months (range: 6 years 3 months-18 years). The majority were palmar (63.4%) with the remainder dorsal. Of the cysts, 43.9% were related to a wrist ligament(s), 36.6% to a joint and 17.1% to the triangular fibrocartilage complex. Of the patients, 91.4% had wrist symptoms: pain (n=29, 82.9%), swelling (n=7, 20%) and/or palpable mass (n=4, 11.4%); 71.4% patients had significant additional wrist abnormalities.

CONCLUSION

Ganglion cysts were frequently found in children referred for wrist MRI.

Lumps and bumps around the foot and ankle: an assessment of frequency with ultrasound and MRI

Benign and malignant tumours and tumour-like conditions frequently present as lumps in the foot and ankle. Although definitive histological diagnosis cannot be ascertained short of a biopsy, most entities can be confidently characterised on ultrasound and/or MRI. Masses in the foot and ankle present with lump, pain, paraesthesia, restricted mobility or a combination of these. In this review we have focussed on the relative frequency of masses in the foot and ankle that present as focal lumps, with a brief description of their typical appearance on ultrasound and MRI. Ganglions were the largest group in our series representing 24 % of the masses, followed by tendon- and ligament-related lesions and, bony lesions representing 16 % and 11 % of the masses respectively.

Fine-needle aspiration biopsy of the distal extremities: a study of 141 cases

We reviewed our cytopathology databases for an 11-year period to identify all fine-needle aspiration biopsy (FNAB) cases of palpable masses of the hand, wrist, ankle, or foot. Cases were included only if there was a subsequent tissue biopsy or a minimum 1-year clinical follow-up. Of 141 aspirates, 41, 23, 34, and 43 were from the hand, wrist, ankle, and foot, respectively. Specific benign or malignant diagnoses were achievable in 71.6% of cases, whereas the remaining cases were given a descriptive diagnosis (26.2%) or, infrequently, a "suspicious for" diagnosis (2.1%). Overall sensitivity and specificity for distinguishing a benign from malignant entity from all 4 sites were 100% and 96%, respectively, whereas positive and negative predictive values were 88% and 100%, respectively. The most common lesion was a ganglion. Of the benign neoplasms, giant cell tumor of tendon sheath (17) and desmoid-type fibromatosis (7) were most common. Of 31 malignancies, 24 were sarcomas: sarcoma not otherwise specified (6), high-grade pleomorphic sarcoma (5), and Ewing sarcoma (3) were most common. Seven nonsarcomas included melanoma (3), metastatic squamous carcinoma (2), and malignant lymphoma (2). An FNAB-procured cytopathologic diagnosis is clinically reliable in a high percentage of distal extremity mass lesions.