Preoperative treatment with radiochemotherapy for locally advanced gastroesophageal junction cancer and unresectable locally advanced gastric cancer. Radiol Oncol. 2015;49:163-172. [PMID: 26029028 DOI: 10.2478/raon-2014-0027]

Advances in Treatment Models of Advanced Gastric Cancer

The prognosis of advanced gastric cancer (AGC) is extremely poor, and the therapeutic effect of traditional palliative chemotherapy is far from satisfactory. To overcome this bottleneck, palliative surgery resection, perioperative chemotherapy combined with surgical resection, hyperthermic intraperitoneal chemotherapy (HIPEC), pressurized intraperitoneal aerosol chemotherapy (PIPAC), radiation therapy, molecular-targeted therapy have been explored in AGC. Although considerable progress has been achieved, there is still no overwhelming therapeutic method. Due to the high heterogeneity of AGC, it is particularly vital to reshaped the paradigm of gastric cancer therapy according to the characteristics of clinical classifications and molecular subtypes.

Pathological complete response from oral chemotherapy combined with trans-arterial chemotherapy and embolization in an unresectable gastric cancer patient: A case report

RATIONALE

Gastric cancer is still one of the most common cancer in East Asia. More than 70% gastric cancer patients are diagnosed at an advanced stage in China. Moreover, about 10% cases are unresectable which usually suffer a poor prognosis with a median survival time of 5 to 12 months. In recent years, some clinical studies found that many unresectable gastric cancer cases could get opportunity for surgery after treatment that improve prognosis significantly PATIENT CONCERNS:: 64-year-old male patient was admitted with upper abdominal pain. Upper gastrointestinal endoscopy showed a large ulcerated tumor located from the cardia to the anterior wall of the upper gastric body. Histopathological examination showed it was moderately differentiated adenocarcinoma. Computed tomography (CT) scan image showed a large bulging mass with internal ulcer at the lesser curvature wall, left gastric artery and coeliac trunk were surrounded by fused lymph nodes.

DIAGNOSES

Based on the histopathological examination and imaging findings, patient was diagnosed advanced gastric cancer and hardly to resect radically.

INTERVENTION

Oral chemotherapy combined with trans-arterial chemotherapy and embolization (TACE) was initiated. Eight weeks after initial therapy, radical laparoscopy-assisted total gastrectomy with D2 lymph node dissection and Roux-en-Y anastomosis were performed successfully.

OUTCOMES

Patient was discharged on postoperative day 11 without complications. Histological analysis of the specimen and resected 31 lymph nodes revealed no malignancy. The patient experienced a pathological complete response (pCR).

LESSONS

In this case, oral chemotherapy combined with TACE which was rarely reported in the treatment of unresectable gastric cancer achieves a great therapeutic benefit. Although further clinical studies will be needed to establish, it may be a potent strategy for degrading stage and supplying a new chance for surgery.

18-Fluorodeoxy-Glucose Positron Emission Tomography- Computed Tomography (18-FDG-PET/CT) for Gross Tumor Volume (GTV) Delineation in Gastric Cancer Radiotherapy

Purpose:

Evaluation of the 18-fluorodeoxy-glucose positron emission tomography-computed tomography (18-FDG-PET/_CT) for gross tumor volume (GTV) delineation in gastric cancer patients undergoing radiotherapy.

Methods:

In this study, 29 gastric cancer patients (17 unresectable and 7 inoperable) were initially enrolled for radical chemoradiotherapy (45Gy/25 fractions + chemotherapy based on 5 fluorouracil) or radiotherapy alone (45Gy/25 fractions) with planning based on the 18-FDG-PET/CT images. Five patients were excluded due to excess blood glucose levels (1), false-negative positron emission tomography (1) and distant metastases revealed by 18-FDG-PET/CT (3). The analysis involved measurement of metabolic tumor volumes (MTVs) performed on PET/CT workstations. Different threshold levels of the standardized uptake value (SUV) and liver uptake were set to obtain MTVs. Secondly, GTV_PET values were derived manually using the positron emission tomography (PET) dataset blinded to the computed tomography (CT) data. Subsequently, GTV_CT values were delineated using a radiotherapy planning system based on the CT scans blinded to the PET data. The referenced GTV_CT values were correlated with the GTV_PET and were compared with a conformality index (CI).

Results:

The mean CI was 0.52 (range, 0.12-0.85). In 13/24 patients (54%), the GTV_PET was larger than GTV_CT, and in the remainder, GTV_PET was smaller. Moreover, the cranio-caudal diameter of GTV_PET in 16 cases (64%) was larger than that of GTV_CT, smaller in 7 cases (29%), and unchanged in one case. Manual PET delineation (GTVPET) achieved the best correlation with GTV_CT (Pearson correlation = 0.76, p <0.0001). Among the analyzed MTVs, a statistically significant correlation with GTV_CT was revealed for MTV_10%SUVmax (r = 0.63; p = 0.0014), MTV_liv (r = 0.60; p = 0.0021), MTV_SUV2.5 (r = 0.54; p = 0.0063); MTV_20%SUVmax (r = 0.44; p = 0.0344); MTV_30%SUVmax (r = 0.44; p = 0.0373).

Conclusion:

18-FDG-PET/_CT in gastric cancer radiotherapy planning may affect the GTV delineation.

Conversion therapy for unresectable gastric cancer

Unresectable gastric cancer cases are often diagnosed at a far advanced stage, which are hard to resect radically and suffer a poor prognosis. Therefore, palliative chemotherapy is recommended as the main treatment by the current clinical guidelines for gastric cancer. Fortunately, in recent years some clinical studies revealed that after treatment with chemotherapy, radiotherapy, targeted therapy, interventional therapy, hyperthermic intraperitoneal chemotherapy (HIPEC) and so on, and multidisciplinary assessment, many unresectable gastric cancer cases could be converted into resectable cases, which consequently prolongs their survival time and improves their quality of life significantly. In the present review, we summarize the status and progress of treatment for unresectable gastric cancer, as well as the strategy and case selection for conversion therapy.