Leptomeningeal Carcinomatosis in a Krukenberg Tumor Associated with Signet Ring Cell Gastric Cancer

Breast cancer, melanoma and lung cancer are the most common solid tumors associated to LCM.[,] However, Lee et al.[] reported that gastric cancer was most common solid tumor to metastasize to the meninges, accounting for 33%, followed by lung cancer (31%), and breast cancer (26%).

The neurological symptoms of LMC are sometimes misdiagnosed as the toxicity of chemotherapeutic agents. We recommend scanning for LMC for patients with neurological symptoms that occurred during treatment. Recent studies suggest that the standard tool for imaging LMC is Gadolinium –enhanced MRI[9] and also cytology of the CSF is the gold standard for LMC cancer diagnosis, although false-negative results have often been reported.[] That a combination of enhanced MRI and CSF cytology be used for accurate diagnosis of LMC.[] Although MRI is generally regarded as superior to CT for the diagnosis of LMD, factors such as cost, availability and patient convenience often dictate that contrast-enhanced CT scans are the first studies ordered for the patient with suspected LMD, especially in the acute clinical setting when hydrocephalus should be excluded prior to lumbar puncture.[]

The prognosis of LMD is unpromising without treatment, with an average survival of 6 weeks following diagnosis.[] With treatment, the average survival is 4 to 6 months[] with survival tending to be longer in patients with breast cancer or hematologic malignancies.

The goals of treatment include prolonging survival, improve neurologic function if not possible palliating symptoms. Intrathecal (IT) chemotherapy using MTX, cytosine arabinoside (Ara-C), and thiotepa is the mainstay of the treatment of LMC,[] though the efficacy and superiority to systemic chemotherapy of this regimen is still unclear. A recent study shows that combination of MTX, Ara-C and hydrocortisone found more effective than the administration of MTX alone in LCM associated with solid tumors.[] A standard induction therapy 10 mg twice a week for four weeks. If there is no response, additional four-week induction therapy or an alternative approach may be considered.[] Recently systemic administration of targeted therapies in selected patients with LMC resulted in clinical benefit as example erlotinib and alectinib in lung cancer.[,] However large-scale clinical studies are required for standardizing intrathecal chemotherapy. On the other hand, Radiation therapy (RT) appears to be more effective at relieving symptoms than does (IT) chemotherapy for symptoms caused by localized leptomeningeal metastases. Also whole-brain radiation is often performed for LMC patients to palliate their symptoms, decrease bulky disease, and correct CSF flow abnormalities.[] 30–36 Gy in 3 Gy daily fractions is recommended by several studies.[,] CSF drainage is also performed to relieve the symptoms of elevated intracranial pressure.[] Corticosteroids is rarely effective in neurological deficits but can improve headaches better than analgesics. Furthermore, anticonvulsants should not be used as prophylactic and reserved for patients with seizures. Emoto and colleagues[] reported that in patients with poor prognostic factors such as poor performance status or MRI-proven LMC, palliative therapy may be the most suitable treatment strategy. In addition, the clinical efficacy of IT MTX in conjunction with RT is illustrated by several study.[,]

In summary, LCM is a rare complication of gastric cancer but recent studies imply that it occurs more than expected but usually might be misdiagnosed. Cytology of the CSF is the gold standard although to avoid from false-negative results, combination of enhanced MRI and CSF cytology be used for accurate diagnosis. Prognosis is poor and worsened if not treated. But, clinical studies are required for standardizing therapy. In conclusion, if the patient who treated for the gastric cancer presenting with neurological symptoms, should be excluded for LCM by clinician.

Disclosure Statement
The authors declare no conflicts of interest.