It is described as a condition in which multiple carcinomas develop simultaneously, usually after spread from a primary source.
It involves more than spread to regional nodes and even more than just metastatic disease .
The term should strictly be used only for epithelial cancers or carcinomas and not for sarcomas or lymphomas, but it has been extended to include all types of cancer that have spread.
Involvement of leptomeninges through seeding through the cerebrospinal fluid, which occurs by direct spread or through the bloodstream. Any cancer can cause this, but adenocarcinomas are the most commonly involved.
Classically it presents with multifocal neurological symptoms and signs. Diagnosis is based on evaluation of clinical presentation, cerebrospinal fluid cytology, and neuroimaging.
Lung lymphangitic carcinomatosis
Diffuse infiltration of the lungs with obstruction of the lymphatic channels.
It can occur with a variety of different cancers, including the lung, breast, stomach, and large intestine.
Spread of metastases in the peritoneum, usually from ovarian and colorectal cancers .
The development of peritoneal carcinomatosis has been shown to significantly decrease overall survival in patients with liver and / or extraperitoneal metastases from gastrointestinal cancer.
Carcinomatosis can be a known disease progression. It may be the recurrence presentation or it may be the main presentation feature. The presentation will depend on where it is affected.
- In the lungs, it can present as shortness of breath and hemoptysis.
- In the liver it often presents as jaundice .
- In the brain there may be headaches, vomiting and neurological features.
- In the bones there may be pain or pathological fracture.
When these features are present, the question is whether this is part of the known disease or something else. For example, if jaundice is due to metastatic carcinoma in the liver or gallstones.
When carcinomatosis is the presenting feature, it is common to look for a primary tumor.
Histology may be anaplastic and not helpful, although improvements in investigational technology are helping to narrow the differential diagnosis.
The objective of the investigations is to confirm the nature of the disease and to assess its severity and extent.
In cases of unknown primary, BCF may show iron deficiency suggestive of gastrointestinal malignancy, microscopic hematuria may reveal occult genitourinary malignancy, and occult blood may indicate a colorectal cause.
In cases where the primary is known, FBC, U&E, creatinine, and LFT may indicate severity.
Modern imaging techniques, such as ultrasound, CT, and MRI, as well as older investigations, such as CXR, provide very good information and an exploratory laparotomy is rarely required today.
It may be necessary to obtain tissue for histology. Techniques now employed to help with differential diagnosis include:
- Light microscopy.
- Immunohistochemistry : The peroxidase-labeled antigen is used to identify specific tumor markers (eg, prostate-specific antigen).
- Electron microscope.
- Chromosome studies : These are occasionally helpful (eg, Epstein Barr virus DNA amplification in suspected occult nasopharyngeal carcinoma).
Tumor markers for leptomeningeal metastases have been identified.
In general, there is no realistic hope of curative therapy, although chemotherapy and radiation therapy can have a palliative effect.
Surgery may be palliative, and tumor ‘shrinking’ before chemotherapy may be helpful.
Resection of liver metastases secondary to colorectal cancer has had some success in limited diseases. There are some subgroups of patients who do relatively well with treatment.
Multimodal treatment (intrathecal chemotherapy, intravenous chemotherapy, whole brain radiation therapy, and radiation therapy to the spinal leptomeninges) has been shown to improve survival rates in patients with leptomeningeal metastases secondary to breast cancer.
Lymphatic carcinomatosis can sometimes be stabilized, or at least slowed down, by chemotherapy.
This can be systemic or by infusion into the cerebrospinal fluid. Radiation therapy may be required if the tumor tissue is bulky or causes symptoms.
Peritoneal carcinomatosis can occasionally be treated with intraperitoneal and / or intravenous chemotherapy.
Treatment can be started postoperatively or chemotherapy drugs can even be instilled into the abdominal cavity during surgery.
These approaches have resulted in demonstrable improvements in survival rates.
Transcatheter arterial chemoembolization (TACE) has resulted in a successful outcome, particularly in patients with neuroendocrine tumors and colorectal metastases.
A microcatheter is inserted into the hepatic blood supply and a combination of chemotherapeutic agents and embolic agents is injected.
Radioembolization promises to play a growing role in the treatments available to treat metastatic disease.
Palliative radiation therapy can often be used to:
- Reduce or eliminate pain from bone metastases.
- Alleviate brain metastases.
- Relieve spinal cord compression or compressive symptoms of visceral metastases (eg, airway or gastrointestinal obstruction).
- Control bleeding, for example hemoptysis or hematuria.
Various ablative techniques have been used to destroy liver metastases, including freezing, microwaves, lasers, and the use of alternating current within the radio frequency range.
Although palliative surgery for malignant intestinal obstruction due to carcinomatosis may benefit patients, it comes at the cost of high mortality and morbidity relative to the remaining survival time of the patient.
Current evidence on the efficacy of debulking surgery followed by hyperthermic intraoperative peritoneal chemotherapy for peritoneal carcinomatosis shows some improvement in survival for selected patients with colorectal metastases, but the evidence is limited for other cancers.
Surgical treatment of bone metastases can improve life expectancy and quality of life.
For patients who are incurable, a frank and honest discussion should take place. This may take more than one session and requires bad news skills.
Other considerations may be death at home and dyspnea in palliative care. Pain control in end-of-life care and nausea and vomiting in palliative care may also deserve attention.
Palliative care should not be viewed as a failure. It is a very demanding and very rewarding aspect of medical practice.