INTRODUCTION:

Bone tumors and soft tissue tumors of the hand and upper limb are uncommon, but every orthopedic surgeon seeing upper extremity problems will see a significant number over time. Their true frequency is unknown because many of these lesions do not require diagnosis.

Aggressive and malignant tumors in the hand and the soft tissues of the upper extremity are very unusual.Unfortunately, this may lead to lack of vigilance on the part of many of the physicians who see them. Lesions that appear innocent may not be and every mass should be considered as potentially troublesome. In the upper extremity bone and soft tissue tumors are normally discovered slightly earlier in their clinical course since they become visible or begin to interfere with function, even when they are relatively small in size.

Many of the lesions that occur in the hand can be diagnosed clinically. On the dorsum of the wrist where joint ganglia are frequent aspiration or transillumination can easily verify the diagnosis. The presence of a mass without known cause and with no history of trauma should be cause for concern. Progressive growth of a mass and a deep seated, firm fixed mass should be considered malignant until proved otherwise and a complete work-up is necessary.

Clinicians should remember that the biopsy is the last step in the diagnostic process. Premature and poorly planned biopsies continue to cause a significant number of unnecessary amputations and may have a profoundly negative affect on chances for survival. Special care should be taken in the case of children with masses in the hand.

CLASSIFICATION OF LESION:

Benign tumors may be classified in three stages. Stage 1 are latent and do not have any characteristics of growth or progressive change. Stage 2 benign lesions are active and Stage 3 benign tumors are aggressive and require complete work-up and a removal with wide margins to avoid possible local recurrence.

The staging system for malignant tumors adopted by the Musculoskeletal Tumor Society, and originally developed by Enneking is based on the histological grade, the local extent, and the presence or absence of metastasis.

Grade is determined by histological parameters. Low-grade tumors generally have few mitotic figures, little if any cellular atypia, and have a relatively non-infiltrative growth pattern. High-grade tumors tend to have marked cellular atypia, hyperchromatism, and nuclear pleomorphism. They often demonstrate an infiltrative growth pattern.

EVALUATION:

When taking the medical history from a patient with a hand tumor one should not forget to inquire about familial syndromes, or disease, history of injury and presence of skin manifestations such as those of neurofibromatosis. The patient's general health should be noted, along with their temperature if infection is suspected.

One of the most valuable pieces of information is the pattern of the pain. Insidiously increasing pain without obvious traumatic cause is generally a bad sign. The pattern of growth of the lesion should also be carefully elicited. Benign lesions tend to grow and shrink, whereas malignant lesions tend to grow progressively. A very rapid development of a tumor or swelling in the hand (hours or days) is generally a sign of a systemic process, such as infection or bleeding.

The physical examination should include the hand, the entire regional anatomy, as well as the regional lymph nodes. These include the epitrochlear lymph nodes of the elbow, the axillary lymph nodes and the cervical lymph nodes. The size, firmness, mobility, tenderness, superficial or deep location, and skin reaction relative to the lesion should be carefully noted. It is important to make an explicit record of these findings so as to be able to document changes, if any.

A patient with a tumor in the hand who sees an orthopedic surgeon should receive a complete evaluation and prompt and appropriate initial management of the lesion. A casual examination and diagnosis are not sufficient. Failure to diagnose cancer is one of the fastest growing areas of malpractice litigation.

If a referral is necessary it should be made in writing and documented in the chart. If no immediate treatment of the lesion is planned, an appropriate follow-up in 6-10 weeks should be scheduled and documented in the chart. A systematic, thorough, and well documented approach to these lesions is essential for the patient's best care and will be invaluable should the lesion develop into a malignancy and questions about the patient's care arise at a later date.

RADIOGRAPHIC EVALUATION:
Two orthogonal plain radiographs of highest possible quality should be the initial examination in all patients with bone or soft tissue tumors of the hand. The plain radiographs remain the cornerstone of accurate diagnosis of bone tumors, and reveal useful information about a significant number of soft tissue tumors.

In general, the plain radiographs should be examined for the features that indicate the lesion's behavior. In addition, the location of the lesion within the bone, the presence or absence of matrix within the lesion, the aggressive or latent features that are seen, the patient's age can be combined to generate an accurate differential diagnosis.

Bone lesions should be classified as latent, active, or aggressive. Latent lesions generally have a sclerotic rim and a very narrow zone of transition show no evidence of periosteal reaction, do not destroy the cortex, and do not extend into the soft tissues.

Active lesions show a pattern of progressive growth with a narrow border of less than 1 or 2mm thickness. They may focally thin or destroy the cortex, and may focally extend into the soft tissues. There may be a minor or moderate periosteal reaction.

Aggressive lesions often have a poorly defined border with a wide zone of transition of several mm's to cm's. They permeate the normal bone, destroy the cortex and extend aggressively into surrounding soft tissues. They may cause a florid periosteal reaction. Further details about the radiographic appearance of the common bone tumors of the hand can be found in the section on each individual tumor.

If an MRI is ordered, the requisition should specify that an extremity coil must be used. The author recommends that MRI's of musculoskeletal tumors be obtained under the direct supervision of the radiologist.

Soft tissue tumors may be visible on plain radiographs. Soft tissue technique should be used to reveal subtle features that are not seen on plain radiographs. Lipomas are seen as a radiolucent mass within faintly radiodense muscle. Hemangiomas and other tumors may have punctate calcifications. The plain film of a soft tissue tumor may also reveal that the lesion is invading or destroying bone, or may have actually originated in a bone and broken out into the soft tissues.

ADVANCED RADIOLOGICAL IMAGING:

The advanced imaging of bone and soft tissues of the hand is beyond the scope of this review. In general, soft tissue masses require analysis by MRI. The orthopedic surgeon ordering an MRI of a hand lesion should specify that the entire lesion should be characterized in all sequences.

Unsupervised, protocol-driven MRI scans of extremity tumors, are usually done without specialized extremity coils and are often of mediocre quality. They may be completely useless for accurate diagnostic or surgical planning purposes.

For bone tumors that are completely contained within bone, a fine cut CT scan is next best imaging choice. MRI images may eventually become necessary if the lesion's characteristics remain unclear. Aggressive bone tumors in the hand will always require MRI imaging.The same recommendations for MRI of soft tissue tumors (see above) apply to bone tumors as well.

Technicium-99 bone scans are primarily used to identify lesions in other parts of the skeleton that may not be clinically or radiologically apparent. The presence or absence of tracer uptake on bone scan of any individual bone lesion is not a reliable indicator of its biologic behavior. The correlation between benign and malignant behavior and bone scan uptake is generally quite poor.

As with all tumors, the imaging studies should be completed prior to the biopsy. Biopsy will alter the appearance of the lesion and may make the diagnosis uncertain or impossible. Biopsy should not be attempted if the differential diagnosis includes more than two or three likely entities. If the differential remains broad the pathologist's job is much harder and the result of the pathologic examination will be less valuable.

Constructing a differential diagnosis in the case of a bone or soft tissue tumor of the hand is primarily an intellectual activity. The clinical and physical exam findings are combined with the radiological appearance of the lesion to construct a list of the two or three most likely entities. It has been the author's experience that the differential diagnosis included on the radiological reports of the bone scan, the MRI scan, or the CT scan are quite variable and often misleading. If there is still considerable doubt as to the nature of the lesion a consultation with an orthopedic oncologist is highly suggested. Alternatively, digital images may be sent to the consultation service at http://www.bonetumor.org.

BENIGN TUMORS OF THE SKIN OF THE UPPER EXTREMITY:
A complete discussion of benign skin tumors is beyond the scope of this review. An excellent chapter on these lesions may be found in Bogumill (Ed) Tumors Of The Hand and Upper Limb, Churchill Livingstone, 1993. Section: Malignant Tumors of the Skin and Subcutaneous Tissue Other Than Melanoma. Basal cell Non-melanotic malignancies are common in the upper extremity and in some populations account for 50% of all cancers.

The lesions may present as small, nodular growths that are skin colored, erythematoid, or pigmented. The classic appearance is that of a raised ulcerated lesion with a slightly raised edge. Neglected basal cell carcinomas may become quite large and fungated. They normally remain locally destructive but do not metastasize. The lesions grow slowly and may appear as a cluster with normal intervening skin.

PATHOLOGY: Basal cell carcinoma demonstrates small-to-intermediate size cells that have a basophilic staining pattern and small, round-to-oval nuclei. There are no bizarre or atypical nuclei seen. There is normally an epithelial pattern with prominent palisades of cells in the periphery of a nest of cells.

SQUAMOUS CELL CARCINOMA OF THE SKIN OF THE HAND AND UPPER EXTREMITY: Squamous cell carcinoma is actually a diverse group of tumors. They may develop as a result of solar radiation, burns or scars, chemical exposure, immunosuppression, irradiation, chronic infection, virus, and chronic draining osteomyelitis.

Patients presenting with thickened scaly lesions of the fingers, hands or the remainder of the upper extremity should have squamous cell carcinoma included in the differential. Squamous cell carcinomas are commonly misdiagnosed as chronic rashes, corns, or dysvascular ulcers. An incisional biopsy done in the clinician's office under local anesthesia is an easy way to resolve any uncertainty. The clinician treating malignant tumors of the upper extremity should become thoroughly familiar with the requirements for staging, documentation, reporting and appropriate surgical margins for excision of these lesions. These are beyond the scope of this review. If any uncertainty remains consider referring the lesion to an orthopedic oncologist, or a dermatologist with a special interest in dermatological malignancy.

MELANOMA OF THE UPPER LIMB: 15% of melanomas occur in the upper limb, and a significant number of these patients will clinically present to a surgeon. The incidence is approximately 1 per 150 persons in the United States, and this number is expected to increase. Melanoma may develop from dysplastic nevi. These nevi are usually larger, irregular in color and borders, and may be focally ulcerated. Any mildly or variably pigmented lesion with an irregular border should be treated with suspicion. Controversy exists as to the value of excisional versus incisional biopsy. The most suspicious area of the lesion should be included in the biopsy to increase the accuracy of diagnosis. An incisional biopsy may be the best approach if the complete (exter? Sounds like) patient of the tumor has a chance of requiring the removal of vital structures.

The lymphatics drainage of the lesion, both locally and regionally, must by examined. The surgeon contemplating the treatment of melanoma of the upper extremity may want refer to Wanebo: Management of Malignant Melanoma in: Moosa Comprehensive Text Book of Oncology, Baltimore, Williams & Wilkins, 1988.

Stage I melanoma is a primary melanoma that is localized or has satellite's within 5 cm of its borders. Stage Ia is the designation for local recurrence of a primary melanoma. Stage II denotes metastases to a single lymph node region. Disseminated cutaneous or visceral disease is Stage III.

Stage I melanoma may be managed by wide excision and elective lymph node dissection. Stage II may be managed by wide excision, therapeutic lymph node dissection, and further treatments depending on the findings of the lymph node dissection. Stage III melanoma is managed by a multi-modality treatment including surgery, chemotherapy and radiation.