"A Man can't make a mistake can't make anything"

Monday, 9 April 2012

ONCOLOGY / ORTHOPAEDI SURGERY SERIE : SOFT TISSUE CANCER / MALIGNANT FIBROUS HISTIOCYTOMA ( definition, signs, symptoms, diagnosis and management)

INTRODUCTION

In America, more than 2000 people are diagnosed with this tumor each year, mostly one type of cancer suffered by children and adolescents, but few cases are found in adults.
      Cancer around the bone itself consists of several types, namely osteosarcoma, Ewing's sarcoma, chondrosarcoma, malignant fibrous histiocytoma, fibrosarcoma, and Chordoma. Malignant fibrous histiocytoma (MFH) is a soft tissue sarcomas of the most frequently in older adulthood. There are several variants of the MFH, storiform-pleomorphic subtype, myxoid, inflammatory and giant cell. Infammatory and giant cell is a rare subtype. Most MFH tumors found in the soft tissue in the extremities and body. Giant cell MFH found in older patients.

CHAPTER I
DISCUSSION

I.1 Definition
Malignant fibrous Histiositoma (malignant fibrous histiocytoma) is a sarcoma that usually begins in the soft tissues. This condition usually appears as a large mass that is painful and can lead to fractures due to bone destruction by tumor spread. 
Malignant fibrous histiocytoma was first introduced in 1961 by Kauffman and Stout. They describe as a tumor rich in histiocytes MFH with storiform growth pattern. In 1977, MFH is considered as soft tissue sarcomas of the most common of adult life.

I.2 Epidemiology
Malignant fibrous histiocytoma of soft tissue usually appears in patients is approximately 50 to 70 years although it can occur at any age. Malignant fibrous histiocytoma is very rare in people less than 20 years. More men than in women. 
Malignant fibrous histiocytoma has a 44% recurrence rate and metastasis rate by 42%. Incidence of metastases to regional lymph nodes are found as much as 12%. 

I.3 Histiologi
      Histologist is divided into four subtypes:
A. Storiform-pleomorphic
  Of these, storiform-pleomorphic is the most common type, accounting for up to 70% of cases, see Figure 1.

Figure 1: A histologic specimen shows fibrous histiocytoma classic storiform-pleomorphic malignant. Microscopically, the pattern shows fasikula short storiform spindle cells radiating from a central point which is mixed with giant neoplastic cells in the pleomorphic

2. Myxoid
Figure 2: Example of histological type myxoid MFH. So that the tumor will be marked as a variant of myxoid, myxoid tissue must explain at least half of the tumor


3. giant cell

4. inflammation 

1.4 Causes and Risk Factors
No one knows the exact cause or causes of malignant fibrous histiocytoma, but studies have shown that people with certain risk factors are more likely to develop the condition. A risk factor is anything that increases a person's chance of developing a disease.
Examples of risk factors for malignant fibrous histiocytoma include:
* Having previous radiation treatment for cancer experience
* Has a history of Paget's disease
* Has a history of sickle cell disease, non-Hodgkin's lymphoma, Hodgkin lymphoma, or multiple myeloma. 

I.5 Diagnosis
a. Clinical symptoms
Levels clinically can be divided according to tumor grading, size and presence or absence of distant metastases. It is very important to determine its prognosis, apart from the anatomical location and histological subtype are included. Malignant fibrous histiocytoma is common in the extremities (70-75%, especially the lower extremities 56%) followed by the peritoneum. Tumors usually grow out of deep fascia or skeletal muscle. Malignant fibrous histiocytoma has been reported on the lungs, kidneys, urinary vesicles, heart, small intestine, orbit, CNS, paraspinal, dural, nasopharynx and neck soft tissue.
Clinical symptoms of this tumor is soft tissue mass that enlarged the premises without the pain, usually with a diameter of 5-10 cm. Mass is usually painless unless pressed on nearby nerves. Two thirds of these tumors are intra muscular. Sometimes the symptoms of hypoglycemia and found a very rapid tumor enlargement in patients with pregnancy, although very rare. Symptoms such as weight loss and fatigue are not typical, but can be present in patients with advanced disease. 
The majority of metastatic disease from sarcoma, including MFH present as pulmonary disease (90%). Extra-pulmonary involvement is not common sites: lymph nodes (10%), bone (8%), liver (1%). 
Figure 3: Clinical photos of MFH of the proximal lateral thigh.

 
Figure 4: Clinical photos of MFH in the palm of the hand

b. Examination Support
Often x-rays will be used as the first imaging test. This is usually followed by MRI. MRI is the most useful test for soft tissue tumors because of the resulting images provide valuable information about the masses such as size, location, and proximity to neurovascular structures. Important to note that the diagnosis of cancer tumor can not be made by MRI alone. For patients who are unable to undergo MRI because of metallic implants such as pacemakers can use the CT scan as the investigation.

Figure 5a: Axial MRI images of MFH in the thigh. Femur bone tumor touch but do not attack into it. Location of the femoral artery and femoral and sciatic nerve can be identified on the MRI to allow for thorough planning of the operation.
 
Figure 5b: A coronal MRI images of MFH in the thigh. MRI allows for accurate measurement of tumor size.

When the diagnosis of sarcoma is suspected, it is important to determine whether the tumor is isolated (local) or has spread (metastasized). When soft tissue sarcomas spread, they most often metastasize to the lungs. Thus, chest CT scans are routinely obtained to determine the presence or absence of metastasis. While sarcomas including malignant fibrous histiocytoma can be spread to other sites such as lymph nodes and bones, but quite rare. The role of tests such as bone scans and PET scans are not really.
PET scans use a high metabolic activity of cancer cells. The technique utilizes a radiolabeled glucose analog fluoro-2-deoxy-D-glucose is metabolized at a higher level by tumor cells. Absorption of FDG uptake values ​​expressed as maximum standards (SUV). While it is a very sensitive test, is not specific for sarcomas. Several investigations have attempted to define the role of PET scan in soft tissue sarcomas (refs. 13, 33, and 34). As our understanding of this new technology develops, diagnostic and staging capabilities will become more refined. For now, the role and cost effectiveness of PET scanning has not been clearly defined. (2,4)


c. Malignant fibrous histiocytoma biopsies
A biopsy is a diagnostic procedure to enforce. A biopsy can be performed with different methods. Needle biopsy involves inserting a small needle into the tumor while to get a needle biopsy specimens can often be done in the doctor's office. If the tumor is in a location that is difficult or felt close to the tumor structure that can be damaged, then CT can be used to guide the biopsy needle.

Figure 6: Needle biopsy of MFH in the thigh. Such as needle biopsy can often be done in the clinic. It is important to draw out the incision to be used to remove the tumor. Biopsy should then be performed along the incision.

An open biopsy is a surgical procedure is usually performed in the operating room under sedation or anesthesia. With incisional biopsy, only a fraction of the tumor is removed for analysis. With excisional biopsy, the entire mass is removed. Excisional biopsy is usually reserved for small tumors (less than 3 cm).
Figure 7: An incision in the upper extremities for sarcomas forearm. Biopsy should be performed with or directly parallel to the incision which allows for limb-saving surgery to remove a tumor. Note that the ellipse has been drawn around the previous biopsy incision. Biopsy channel should be cut at the time of definitive surgery to prevent local recurrence.

Tissue obtained from biopsies were evaluated by a pathologist. The pathologist uses a number of diagnostic tools including light microscopy, immunohistochemistry, electron microscopy, and molecular studies to make a diagnosis. In addition to making the diagnosis, the pathologist also provides an important part of information is called a class. This class refers to the appearance of the tumor under a microscope and a reflection of the aggressiveness of a tumor. High grade tumors behave more aggressively, which means they have a higher tendency to recur and spread. Low grade tumors are less aggressive and have a lower tendency to recur and spread. This class does not guarantee the behavior of the tumor but rather is one factor that helped the team to make treatment recommendations.
After all the research study and a biopsy was performed, stage of disease can be diberika. The most common scoring system used is a system (American Joint Commission on Cancer) AJCC for soft tissue sarcomas (Table 1). Patients often inquire about their disease stage. Stadium only provide guidelines for the treatment team about how best to manage the tumor is given to optimize clinical outcomes.

Table 1: American Joint Committee on Cancer (AJCC)
Staging Soft Tissue Sarcoma Systems, Issue 6

I.6 Treatment
Basically there are three main types of treatment that need to be coordinated to treat this MFH:
A. Operation
2. Radiation
3. Chemotherapy
A. Surgery for malignant fibrous histiocytoma
Surgery is the cornerstone of treatment for all soft tissue sarcomas. The goal of surgery is to eradicate the disease in all affected areas. For extremity sarcomas, surgical options fall into two categories: limb-sparing surgery and amputation. Historically, soft tissue sarcoma treated by amputation. As our understanding of sarcoma has grown, so has the treatment. Several studies have shown no difference in survival compared to patients with limb-salvage amputation. In a randomized clinical trial run by the National Cancer Institute, there was no difference in overall survival for patients with soft tissue sarcoma who had amputations (70%) compared with those who run the amputation (71%). Aligning the oncologic and functional outcomes is extremely complex and subjective. It is very important for the patient and the treating surgeon to discuss the prognosis of all the options before surgery. Tumor resection and reconstruction is sometimes necessary depending on tumor size and structure of what needs to be sacrificed. For example, bones or joints may need to be reconstructed or soft tissue flap may be necessary for wound coverage.
Once the tumor has been removed, a pathologist analyzes the specimen and confirm the grade of the tumor and margin. Margin refers to the outermost edge of the resection specimens. A negative margin indicates that there are no tumor cells in the tumor periphery suggests that complete resection is achieved. A positive margin means that the tumor cells were found in the periphery of the resection specimen, which means there is microscopic disease and the possibility of a remaining. To achieve negative margins at surgery, unfortunately not always possible to do so. Surgical procedures for sarcomas are classified as described in Table 2. The procedure may be, broad and radical attempt to obtain negative margins. (2)

Table 2: Classification of surgical resection
for the treatment of sarcoma


Figure 8: Intra-operative photograph of MFH of the scapula is removed using a limb salvage surgery. A cuff of normal tissue that is stored with the tumor mass was never really exposed during surgery. Malignant fibrous histiocytoma,

2. Malignant fibrous histiocytoma of radiation to
Radiation therapy is administered by a radiation oncologist. The purpose of radiation is to increase local tumor control with a slew of microscopic residual disease. Typical radiation doses varied from 45 Gy to 65 Gy.
There are several different ways to administer radiation. The most common form used is external beam radiation may be given before surgery, intra-operative, post-surgery, or in some combination. Each has advantages and disadvantages, see Table 3. For tumors that are in contact with major nerves and blood vessels, pre-operative radiation can potentially shrink the tumor, making limb-sparing surgery possible or easier. The main disadvantage to pre-operative radiation is related with the postoperative wound complications. Postoperative radiation is probably the most commonly used modality. Usually the pre-and post-operative radiation is administered over a period of 5 weeks. Intra-operative has the advantage useful for treating a large retroperitoneal sarcomas where it is difficult to obtain local tumor control.


Table 3: Advantages and disadvantages of the radiation therapy


Another way of giving radiation is a technique called brachytherapy. Once the surgeon has removed the tumor, radiation oncologist and then place an empty catheter in the operating bed. After the wound began to heal (about 5 days after surgery), the catheter is filled with radioactive material that sits in the surgical bed for 5 days. This allows for higher doses of radiation over a short period of time avoiding the need to travel daily for radiation treatments for several weeks.

Figure 9: Brachytherapy catheter across the field of operation. Once the tumor has been completely cut, the radiation oncologist to put an empty tube (catheter) at the base of the wound and sew the tube into place. The wound is carefully closed.

Radiation is known to have side effects such as problems of tissue and scarring, resulting in muscle stiffness and skin discoloration .. The most serious complications arising from radiation is the development of second cancers in radiated fields is called Kaposi's post-radiation or radiation. Radiation sarcomas are rare and occur in less than 5% survive for long. 

3. Chemotherapy for malignant fibrous histiocytoma

The role of chemotherapy in the treatment of malignant fibrous histiocytoma is not entirely clear. Several clinical trials combining chemotherapy drug doxorubicin has shown a trend of increasing survival without major impact on survival hidup.Pada meta-analysis study conducted on 1,600 patients concluded that soft tissue sarcomas addition of chemotherapy improved overall survival with less than 10%. Better outcomes in patients with extremity tumors than in patients with axial or retroperitoneal tumors. More recently, clinical trials combining ifosfamide and doxorubicin have shown improvement in disease-free survival. One major limitation of chemotherapy is the toxicity associated with the doses required to have a significant impact on disease-specific. The addition of support such as hematopoietic growth factors for better survival was observed.

The decision to combine chemotherapy in the treatment of MFH should be done with the guidance of a medical oncologist. Chemotherapy may be given to patients already have metastatic disease or who are at highest risk for developing metastatic disease. Most often, chemotherapy is likely to be given in a clinical trial setting. 

I.7 Prognosis and Outcomes
Prognostic factors are known to correlate with survival in patients with malignant fibrous histiocytoma including tumor grade, depth, size, metastasis status, patient age and histological subtype. Good prognostic factors include age less than 60 years, tumor size less than 5 cm, superficial location, light, absence of metastatic disease, and the myxoid subtype. Older patients with large (> 5 cm), high grade tumors do not have as good a result. For example, patients with small low-grade tumors tend to achieve a complete cure. For patients with large tumors, deep, high grade tumors (Stage III), 5-year survival estimate the range of 34-70%.

The local recurrence of tumor recurrence in the same location, will occur in approximately 20-30% of all patients with soft tissue sarcomas. The lowest local recurrence in extremity sarcoma and retroperitoneal sarcoma highest, head and neck. This distribution is directly related to the ability to completely resect the tumor during surgery. High local recurrence was observed in the setting of surgical margins is more difficult to achieve in the outer extremities of the anatomical location (Ref. 18). Does local control impact on overall survival is unclear and remains controversial. It is very important for patients to understand that the data on outcomes and survival comes from the most heterogeneous, retrospective analyzes that do not have the strict inclusion criteria. Survival statistics quoted are most useful for treating physicians to guide therapy and may be of limited value for individual patients. 

Table 4: malignant fibrous histiocytoma of clinical results from cancer center

Probably about 1/3 of patients with extremity MFH and closer to half of patients with retroperitoneal MFH will experience a recurrence either in the (local recurrence) or in remote locations (distant recurrence or metastasis). Most recurrences usually develop within the first 2 years after treatment but can occur at any time during the lifetime of the patient. Frequency varies according to individual risk factors
have to develop a recurrence. The average patient was followed for about 10 years. Patients with large or high-grade tumors are likely to be evaluated every few months earlier. Follow-up examination consisted of physical examination and evaluation of the chest wall in the form of an x-ray or CT-scan. Depending on the circumstances, MRI of the primary site can be obtained.

If recurrence is detected, the treatment team work together again to determine the role of surgery, radiation, chemotherapy, and. Most local recurrences can be effectively treated with additional surgery. For inoperable recurrent local disease, about 2/3 of patients experience long-term survival. If there is no radiation before the affected areas should receive radiation. Metastatic disease is the most serious type of recurrence and most commonly occurs in the lungs. Individual treatment plans vary significantly depending on the number of patient factors and diseases and the limitations imposed by previous treatments. For patients who have lung metastases is surgery to achieve survival in approximately 20% to 50% of patients. Chemotherapy is often used for the treatment of patients with recurrence. Unfortunately, patients with unresectable recurrent disease have a poor prognosis.



No comments:

Post a Comment

Post a Comment