Kaposi Sarcoma

Of the seven types of Sarcomas, the incidence of Kaposi Sarcoma, a type of skin cancer is found to be more prevalent in persons with immune deficiency disease like AIDS. The rate of Kaposi Sarcoma is reported to be 20 times more. It is estimated that 15% of HIV infected persons will develop Kaposi Sarcoma. The weakened immune system is unable to fight the Kaposi Sarcoma Herpes Virus. Thanks to HAART (highly active anti-retrovirus therapy), the incidence rate has decreased.

Sarcoma is a rare type of cancer. The malignant tumors occur in the body's connective tissues - the tissues that support, connect and bind various parts of the body. Muscles, fat, fibrous tissues, nerves, blood vessels, cartilage, bones and joint tissues are all connective tissues.

Sarcomas fall into three broad categories.

Soft tissue cancers

• Benign (non cancerous)
  
• Malignant (cancerous)

Primary bone cancer

Gastro-intestinal stromal tumors

Kaposi Sarcoma is a soft tissue sarcoma, malignant in nature.

Kaposi Sarcoma causes

Human herpes virus 8 (HHV8) also called Kaposi Sarcoma associated herpes virus (KSHV), a virus causes the infection. Though as many as 1 in 20 people may have this virus sans any symptom, certain groups of people are vulnerable to its effect and develop Kaposi Sarcoma. Mostly, people whose immune system isn't working properly either due to a medical condition or medication (immunosuppressive medications) can develop Kaposi sarcoma. The weakened immune system allows the HHV8 to multiply to high levels in the blood thus increasing the chance of developing Kaposi Sarcoma.

Kaposi Sarcoma symptoms

The first symptom is the lesion appearing on the skin. It can be bluish-red, or brown or purple spots or lesions on the skin, flat or as a slightly raised bump, linear or in a symmetrical distribution. In fact, the appearance of the lesion indicates the possibility of the person being infected with HIV or the condition it causes, namely, AIDS. Kaposi Sarcoma can also affect internal organs which can lead to a range of symptoms, depending on the organ that is affected.

Skin lesions

The lesions can appear anywhere on the body but in most cases the lesions appear on the face (ears, mouth and tip of the nose), legs and feet and the genital area. It could occur in a single area in the beginning. These can merge to form a large tumor.

Lymph nodes: Swollen lymph nodes are the symptoms of Kaposi Sarcoma affecting the lymph nodes.

Arms and legs: If Kaposi Sarcoma affects the lymph vessels, there is buildup of fluid in the arms and legs. This condition is called lymphoedema.

Lung problems: Kaposi Sarcoma affecting the lungs can lead to breathlessness and coughing up blood.

Digestive system: Nausea, vomiting, stomach pain and diarrhea are symptoms related to Kaposi Sarcoma affecting the digestive system.

HIV related Kaposi Sarcoma: Being HIV positive or having AIDS increases the risk factor of HIV-related Kaposi Sarcoma. Compared to women, men have higher chances as also gay and bisexual men who are HIV positive are at risk of HIV related Kaposi Sarcoma.

Classic Kaposi Sarcoma: A rare condition, classic Kaposi Sarcoma affects middle-aged and elderly men of Mediterranean or Ashkenzi Jewish descent. There is a high possibility of being born with a pre-existing genetic vulnerability to the HHV-8 virus.

Endemic African Kaposi sarcoma: This type is a common cancer in parts of Africa with high levels of HIV. In most cases, the reason is either undiagnosed HIV infection or a pre-existing genetic vulnerability to HHV-8 virus.

Transplant related Kaposi Sarcoma: After an organ transplant, a strong immune system can reject the new organ. In order to weaken the immune system thereby preventing the rejection of new organ, medications (immunosuppressant) are used. This makes the person vulnerable to HHV-8 virus infection.

Tests for diagnosis of Kaposi Sarcoma

For a definitive diagnosis, a small amount of tissue is removed for examination under the microscope. If the biopsy results confirm, further tests are required to know the spread to internal organs. X-ray, Endoscopy, Bronchoscopy, CT scan and photography are the diagnostic tests that reveal the spread of cancer - staging of the cancer.

Kaposi Sarcoma staging

For all cancer types, staging determines the treatment options and the patient's survival outlook. With regard to Kaposi Sarcoma, the staging is largely influenced by the person's weakened immune system and the presence of AIDS related infections. For Kaposi Sarcoma staging, doctors use the AIDS Clinical Trial Group system. Three factors are considered under the AIDS Clinical Trial Group system while categorizing patients in good risk group and poor risk group.

• The extent of the tumor
  
• The status of the immune system as measured by the number of certain immune cells (CD4 cells) present in the blood
  
• Systemic illness

These factors have two subgroups. After assessing the features, the type of Kaposi Sarcoma, doctors discuss the most suitable treatment option.

Kaposi Sarcoma treatment

Kaposi Sarcoma is incurable but can be controlled with treatment. The stage, the type of Kaposi Sarcoma, the number of lesions, age and general health are considered by the doctors before determining the appropriate treatment option. It could be chemotherapy, immunotherapy, antiviral drugs or radiation therapy. There are possible side effects for each of these treatment options.

Chemotherapy: Chemo drugs can be given into a vein or by mouth to enter the blood stream to reach all areas of the body. Chemotherapy is a treatment option when the cancer has spread to many areas of the body. Chemo drugs cannot be given for long periods as it can weaken the immune system. Particularly for HIV infected patients, there is a need to strengthen the immune system. In such cases, combined antiretroviral therapy can be used along with chemo drugs. Drug interaction is taken into account before prescribing the combined therapy. After tests indicate control of Kaposi sarcoma, chemo drugs may be stopped and the treatment may continue with combined antiretroviral therapy alone.

Immunotherapy: Transplant related Kaposi Sarcoma is usually treated using immunosuppressant medications or immunotherapy. The aim is to strengthen the immune system so as to fight the HHV-8 while ensuring the body doesn't reject the transplanted organ. Alternatively, radiotherapy or chemotherapy may also be considered.

cART: Combination antiretroviral therapy (cART) involves the use of several different medications called antiretroviral therapy to lower HIV levels in the blood by slowing down the rate at which the virus can multiply.

Radiotherapy: If Kaposi Sarcoma spreads and affects the internal organs, symptoms such as breathlessness and swelling of the arms and legs cause immense distress. Radiotherapy is chosen as a treatment option as the high-energy rays destroy cancer cells cautiously without harming the healthy cells in the body.

Surgery: If the lesions are small, after injecting local anesthetic to numb the area, surgery is performed to remove the lesion.

Cryotherapy: Cryotherapy involves freezing small lesions with liquid nitrogen.

Retinoic acid gel: Retinoic acid is applied directly to the skin several times a day on the small lesions. After few weeks of application, significant improvement can be noticed.

Bone Sarcoma

The word 'sarcoma' is derived from the Greek word for 'fleshy'. Sarcomas arise from Mesenchymal tissue which is the precursor to fibrous tissue, muscle, bone and fat. Bone sarcoma is malignant tumor or cancer of the bone. The difference between the terms sarcoma and carcinoma is that while sarcomas spread through blood, carcinomas through lymph fluid to the nearby lymph nodes.

Symptoms of bone sarcoma

• Pain in the bones.
  
• Pain may worsen in the nights.
  
• Swelling, redness and tenderness at the site of bone pain.
  
• Swelling of the leg or arm in longer bones such as above or below the knee or upper arm, shoulder etc.
  
• Bone fracture after a routine movement – like throwing a ball.
  
• As cancer weakens bones, broken bones tend to occur more easily.
  
• Fatigue, fever and weight loss and anemia are other signs.
  

Causes of bone sarcoma

The cause is unknown in most cases although bone sarcoma can develop from benign lesions in the bone and areas that previously received radiation. Therefore persons who received radiation therapy or chemotherapy can be at increased risk. A genetic syndrome called Li Fraumeni and retinoblastoma and a disease called Paget's Disease are also associated with sarcoma.

Types of bone sarcoma

1. Osteosarcoma that occurs in the bones around the knee and upper arm.
2. Chondrosarcoma that begins at the cartilage and ends of bones and lines of joints and in pelvis, upper leg and shoulder.
3. The Ewing sarcoma family of tumors that occurs in bone but may also be present in the connective tissues located in the pelvis, legs and arms.
4. Multiple Myeloma which is a cancer of plasma cells that originates in bones.

Bone sarcoma diagnosis

A doctor examines the patient physically after ascertaining family medical history. Then the physician may recommend the following diagnostic tests:

• X rays in various parts of the body to show location, size and shape of bone tumor.
  
• Bone scans
  
• CT scans which reveal cross sectional images to check if the tumor has spread.
  
• MRI scans
  
• PET scans that image the body's metabolic action to show if cancer has spread.
  
• Biopsy
  

Treating Bone Sarcoma

Surgery plays a primary role in the treatment of bone sarcoma. The goal of surgery is twofold. On the one hand it can remove the cancerous tumors and restore the physical function and appearance. On the other hand, a cuff of normal tissue is taken from around the tumor cells to minimize the risk of tumor recurring at the local resection site.

After surgery, the reconstructive or plastic surgery team performs the delicate task of replacing bone. Musculoskeletal oncologists and reconstructive plastic surgeons use donor bone, the patient's own bone from other sites and metal implants to reconstruct limbs and restore function.

Radiation therapy: This can be performed before or after surgery or even during surgery though the use of brachytherapy. Radiation therapy is used to treat tumors or when there is disease recurrence at the site of the original tumor or other localized site. This is especially used in treating chondrosarcomas more often than bone sarcomas.

Chemotherapy: Chemotherapy is given before surgery in order to shrink the tumor and allow for better resection. Surgery and radiation can only act on a small area tumor site. Chemotherapy kills any cancer cells floating undetected elsewhere in the body.

Follow-up depends upon the grade and type of bone sarcoma. In case of Osteosarcoma and Chondrosarcoma, follow-up includes physical exam, chest x-ray which should be performed every three months for at least two years initially and then after four months for a year and then every six months for two years and subsequently annually.

Paraneoplastic Syndrome

The first report of Paraneoplastic syndrome is attributed to a French physician, M Auche, who described the involvement in a peripheral nervous system in cancer patients in 1890. This syndrome is a group of signs and symptoms caused by a substance that is produced by a tumor, or in reaction to a tumor. Paraneoplastic syndrome is defined as a rare disorder triggered by a response to neoplasm of an immune system that is altered. These are clinical syndromes produced by tumor although they occur remotely from the tumor itself.

The symptoms may be of any nature – endocrine, neuromuscular or musculoskeletal, cardiovascular, cutaneous, hematologic, gastrointestinal, renal or miscellaneous. Fever is the most common sign. Other clinical symptoms may be benign but syndromes could be varied; from a malignant carcinoid syndrome to Cushing syndrome. In cancer patients, the central nervous system involvement can be detected and it is a prominent manifestation of cancer.

Because of their protean manifestations, Paraneoplastic syndromes are managed by a medical team of physicians, including medical oncologists, surgeons, radiation oncologists, endocrinologists, hematologists, neurologists and dermatologists.

Causes

This syndrome can be due to a number of causes, including hormones or biologically active products, made by tumor, which blocks normal hormone, autoimmunity, immune-complex production and immune suppression. But, this is not caused by the primary tumor itself, or by its metastases, or by compression, infection, nutritional deficiency, or treatment of tumor.

Patients with family history of malignancies are at an increased risk and should be screened for cancer. Paraneoplastic syndromes occur typically among middle-aged to older patients. They are mostly diagnosed with cancers of the lung, breast, ovaries, or lymphatic system or lymphoma.

These symptoms sometimes appear before the diagnosis of a malignancy. When the tumor breaks immune tolerance and begins to attack the normal tissue expressing that protein, this syndrome become prominent.

Types of Paraneoplastic Syndrome

Due to the complexity of this syndrome, its clinical presentations may vary greatly. Hence, Paraneoplastic syndromes is divided into four main categories - endocrine, neurological, mucocutaneous, and hematological syndromes as well as a host of others including rheumatologic, renal, gastrointestinal, Cutaneous and miscellaneous.

Fever, dysgeusia, anorexia, and cachexia are included under miscellaneous category. Fever is associated with lymphomas, acute leukemias, sarcoma and carcinomas.

Rheumatologic syndrome includes polyarthritis, particularly in patients with myelomas, lymphomas, acute leukemia, malignant tumors of the colon, pancreas, prostrate. Scleroderma may precede the evidence of tumor. Widespread form of malignancies of breast, uterus and lung can be observed.

Renal syndrome is characterized by hypokalemic nephropathy, and it occurs in 50% of individuals with ACTH secreting tumors of the lung. Nephrotic syndrome is observed in patients with Hodgkin lymphoma, non Hodgkin lymphoma, malignancies of lung, thyroid, colon, breast, ovary and pancreatic head.

Watery diarrhea and electrolyte imbalance, leads to asthenia, confusion and exhaustion, all characteristic of gastrointestinal syndromes. Severe prostaglandins lead to malabsorption and unavailability of nutrients.

Hematologic syndromes are related to anemia, thrombocytosis, disseminated intravascular coagulation, and leukemoid reactions from several types of cancers. Leukemoid reactions due to immature white blood cells in the blood stream are accompanied by hypereosinophilia and itching.

Cutaneous syndromes are manifested by itching and flushes, alopecia, or hypertrichosis. Blackish pigmentation of the skin usually occurs in patients with metastatic melanomas or pancreatic tumors.

Endocrine syndromes resemble common endocrine disorders. Increased serum and urine cortisol concentrations are common examples of this malignancy.

Neurologic or neuromuscular syndromes relate to cancers and such disorders affect 6% of all patients with cancer. Neuromuscular symptoms mimic common neurological conditions. Myasthenia gravis is a common Paraneoplastic syndrome in patients with thymoma, a malignancy arising from epithelial cells of the thymus.

Paraneoplastic limbic encephalitis is characterized by depression, seizures, irritability and short term memory loss and neurologic symptoms rapidly resemble dementia.

Paraneoplastic cerebellar degeneration causes gait difficulties, dizziness, nausea and diplopia. Sensory neuropathy affects lower and upper extremities and there is progressive memory loss, either symmetric or asymmetric.

Diagnosis

As Paraneoplastic syndromes may evolve over weeks to months, they usually stabilize regardless whether the patient's underlying condition improves or worsens. Since this is the first manifestation of cancer, patients should undergo investigation for cancer. Other diagnoses are membrane disease, dementia, encephalopathy, encephalitis, myelitis, anemia, bone marrow failure, chronic fatigue syndrome, mixed connective tissue disease, polycythemia vera and polymyalgia rheumatica among others.

Complete laboratory tests in blood, urine, cerebrospinal fluid, protein electrophoresis, assays for auto antibodies, Endoscopy and imaging studies including whole body scans and FDG-PET scans are prescribed to detect extremely small tumors especially useful for patients with neurologic diseases.

Treatment of Paraneoplastic Syndrome

Treatment for this syndrome varies depending upon the type and location of tumors. The first option of treatment of the underlying tumor is by therapeutic protocols, a combination of surgery, radiation, chemotherapy. Second therapeutic option is for patients with clearly identifiable antibodies by intravenous immunoglobulins, steroids, or plasma exchange.

Surgical treatment is typically directed toward the underlying neoplasm although some Paraneoplastic disorders may resolve rapidly without surgery on the primary tumor.