Metastatic malignant melanoma to the foot and ankle: a review of the literature and case report

[Foot and ankle tumours : Part II: Malignant bone tumours and soft tissue tumours of the foot with differential diagnostic hints]

CLINICAL ISSUE

Both benign and malignant tumours are encountered in the foot and ankle. Due to their rarity, however, diagnosis is often uncertain. Usual criteria such as tumour size, invasiveness or pain fail to differentiate benign from malignant neoplasias.

STANDARD RADIOLOGICAL METHODS

Plain radiography and-due to the complex foot anatomy-CT are important in the diagnostic evaluation of primary bone tumours. In the case of soft tissue tumours, ultrasonography is used to identify ganglion cysts. Tumour evaluation and staging are then performed using MRI. Nuclear imaging comes into play when multifocal, metastatic or systemic spread of the disease is suspected or if a biopsy procedure is planned.

METHODICAL INNOVATIONS

For the role of dual-energy CT, please refer to part I. Whether dual-energy CT is suitable to assess bone marrow oedema patterns is still debated.

SPECIAL FEATURES OF FOOT AND ANKLE TUMOURS

Primary bone tumours generally present in the ankle or the hindfoot. Malignant bone tumours, e. g. chondrosarcoma, are primarily found in the latter. On the other hand, soft tissue tumours generally present in the mid- and forefoot regions.

ACHIEVEMENTS

While the radiologic diagnostic evaluation of pedal bone tumours is quite reliable, caution is urgently needed in the case of soft tissue tumours because there are many confusing differential diagnoses.

PRACTICAL RECOMMENDATIONS

Proper X‑ray examination of the foot (at least in two plains) or with special views according to bony pathology is needed. All soft tissue masses that are not cysts should be evaluated further. MRI remains the diagnostic modality of choice but never stands alone! Caution: Size and well-defined margins of pedal soft tissue tumours are not considered criteria regarding whether a tumour is malignant or not.

Metastatic Pulmonary Adenocarcinoma of the Talus: A Case Report

Tumors rarely metastasize to the foot bones; however, a misdiagnosis can lead to a poor outcome. These metastatic tumors can cause foot pain and other symptoms in patients who are asymptomatic for the primary tumor. To accurately diagnose acrometastases, the attending physician must have a high index of suspicion and conduct a thorough examination and appropriate diagnostic testing. We present a rare case of metastatic pulmonary adenocarcinoma of the talus, which was initially misdiagnosed as a benign bone cyst. After pulmonary adenocarcinoma was diagnosed, the patient received multidrug treatment for the primary and metastatic lesions and was still responding well at the 12-month follow-up visit.

Metastases to bones of the foot: a case series, review of the literature, and a systematic approach to diagnosis

Metastatic lesions to the bones of the foot are rare but pose a challenge to the treating surgeon because of variation in presentation. Cases may present as a painful or swollen toe or as an infection resistant to antibiotics, or they may mimic inflammatory arthropathy. As such, diagnosis may be delayed. Also, with the advent of new therapies for certain cancers, patients living longer have time to develop metastases. The incidence of metastases to the foot is changing. The senior author (HD) has managed 3 consecutive cases of tumorous lesions metastasizing to the foot. Patients included 1 man and 2 women, with an average age of 76.7 years (range, 57-88 years). Open biopsy was performed in 2 cases, whereas true-cut needle biopsy was performed in 1 case. The average follow-up was 16.2 months (range, 8.5-29 years). The pattern and incidence of foot metastases may be changing. Early and accurate diagnosis may help improve patient survival. A working protocol is presented here that can help in diagnosing such lesions.

Metastatic skeletal disease of the foot: case reports and literature review

BACKGROUND

Metastatic disease of the skeleton occurs in at least 20% to 30% of patients with malignancy, but metastasis to the foot and hand (acrometastasis) is extremely rare (0.007% to 0.3%). Metastases to the feet are even rarer and have been reported in half to one-third the rate for hand metastases. Failure to recognize these lesions has led to delayed diagnosis and/or inappropriate treatment. The purpose of this report is to highlight the clinical and radiologic features that aid in the diagnosis and potential treatment of this condition along with a pertinent review of the literature.

MATERIALS AND METHODS

In a retrospective review of 694 patients with histologically proven metastatic skeletal disease (January 1988 to January 2007), 14 cases of metastatic lesions to the foot were identified.

RESULTS

The most frequent primary site was in the genito-urinary system in eight patients and the most common bones involved were the calcaneus and the talus in six patients each. All patients died after a mean survival of 14.8 (range, 1 to 54) months after diagnosis of metastases.

CONCLUSION

Although metastatic disease of the foot is rare, it should be considered in the diagnosis of a painful foot, especially if suspicious radiographic changes are present in an older patient. The common primary sites are the genito-urinary, lungs, breast, and the colo-rectum. Treatment is usually palliative to reduce pain and maintain function.

Delayed presentation of metastatic melanoma of the cervical spine

A 54-year-old woman presented with neck pain and bilateral shoulder pain. The pain was of varying intensity and was present with activity as well as at night and at rest. She had weakness of her triceps and finger intrinsic muscles. Her past medical history included stage IV melanoma for which she underwent an excision from the right flank area 25 years ago. She was cleared from any disease 5 years after the excision. Magnetic resonance imaging of the cervical spine revealed increased signal intensity in the C7 vertebral body with soft tissue extension into the epidural space. Two weeks after initial presentation the patient underwent a C7 corpectomy and fusion. The C7 vertebral body was grossly pathologic and tissue samples revealed metastatic malignant melanoma. During the 2 weeks following the fusion the patient developed increasing pain and generalized weakness. Repeat MRI of the cervical spine revealed a large soft tissue intensity extending in the spinal canal from C6 to T2. Several days later the patient developed an acute onset of lower extremity weakness as well as urinary incontinence. The patient opted to pursue hospice care, and she died 3 weeks later, 8 weeks after the initial presentation.

Rare clinical experiences for surgical treatment of melanoma with osseous metastases in Taiwan

BACKGROUND

Malignant melanoma occurs infrequently in Taiwan. Once it has progressed into osseous metastases, the prognosis is poor. There are no reported clinical experiences of surgical management in this area.

METHODS

To improve our understanding of the rare clinical experiences, we retrospectively investigated clinical characteristics, radiological findings, treatment modalities, survival outcomes and prognoses of 11 Taiwanese patients with osseous metastasis of melanoma treated surgically at two national medical centers, National Taiwan University Hospital and National Cheng Kung University Hospital from January 1983 to December 2006.

RESULTS

Six patients suffered from acral-lentiginous melanoma. Nine patients sustained multiple osseous metastases and most lesions were osteolytic. Nine patients also had sustained metastases to other organs including liver, lungs, lymph nodes, brain and spleen. Second malignancies including lung cancer, thyroid papillary carcinoma, renal cell carcinoma and cervical cancer co-existed in four patients. The interval from the initial diagnosis of melanoma to the clinical detection of osseous metastases varied from 0-37.8 months (mean 9.75 months). Metastatic melanoma was invariably fatal; the mean survival time from bone metastases to death was 5.67 months.

CONCLUSION

Due to the high morbidity and poor survival of Taiwanese patients with osseous metastases of melanoma, surgical treatment should be directed towards pain relief and the prevention of skeletal debilitation in order to maintain their quality of life.

Lower extremity reconstruction

The current recommendation for surgical treatment of tumors of the lower extremity is a limb-sparing resection. Limb-sparing resection coupled with complex reconstructive techniques and complemented by new chemotherapeutic agents and adjuvant radiation therapy has allowed us to achieve survival rates that are comparable to those of amputation with a better functional outcome. Recent advances in microsurgical techniques and the associated technologies and a better understanding of microvascular anatomy has allowed us to customize flaps to the specific needs of the patients and to achieve a lower donor site morbidity. Increased communication between the specialties of the multidisciplinary treatment team has also improved outcomes. The reconstructive component has become an integral part of the multidisciplinary care for patients with lower extremity tumors. It not only allows them to rapidly resume adjuvant therapies but also enables them to more easily resume their activities of daily living.

Foot malignancies: a multidisciplinary approach

Malignant osseous and soft tissue tumors of the foot are rare and should be considered in patients who have foot-related symptoms. Most sarcomas affect patients who are older than 55 years; however, many young patients who are otherwise healthy, may present with malignant foot and ankle lesions. In addition to benign and malignant neoplasms, pseudotumorous conditions mimic neoplastic lesions and should be differentiated before any treatment is undertaken. Invasiveness is a characteristic of sarcomas. The foot is a terminal anatomic structure, with closed and tight compartments and well-vascularized tissues, that predispose it to hematogenous and lymphatic metastases. Patients who have a malignant foot tumor should be referred to an orthopedic oncologist for further evaluation and treatment. The goals of treatment include local tumor control, restoration of function and stability during standing and walking, long-term survival, and improved quality of life. In most cases, wide surgical margins require a ray, Syme, midtarsal, or below-the-knee amputation. Recent advances in chemotherapy and radiotherapy have allowed limb salvage procedures with wide tumor resections. Because overall survival is greatly improved in these patients, the reconstruction of skeletal defects needs to be more functional and durable. After tumor resection, reconstruction of the skeletal and soft tissue defects is possible by using bone allografts or vascularized autografts, arthrodesis, and free vascularized musculocutaneous flaps.