Bar Chikman

The accuracy of sentinel node mapping according to T stage in patients with gastric cancer

BackgroundSentinel lymph node (SLN) mapping has been recently introduced to the field of gastric cancer. To the best of our knowledge, no study has dealt with the accuracy of SLN mapping according to the T stage of the primary tumor. The aim of the present study was to evaluate SLN status according to the T stage of the primary tumors.MethodsEighty patients with gastric cancer underwent SLN mapping with patent blue dye during gastric resection.ResultsForty-seven patients underwent distal subtotal gastrectomy; 17 patients, proximal gastrectomy; 14, total gastrectomy; and 2, gastric stump resection. SLNs were stained in 61/80 patients (76.3%). The number of stained SLNs varied from 1 to 16 (mean, 3.3). Patients undergoing proximal gastrectomy had a mean of 3 stained SLNs, whereas patients undergoing distal subtotal gastrectomy had a mean of 2.8 stained SLNs. In 55/61 patients (90.2%) with stained SLNs a positive correlation was found between the presence of metastases and stained or non-stained SLNs. Ten out of 11 patients (90.9%) with T1 tumors (mean, 3.27 SLNs per patient) and 15/17 patients with T2 tumors (88.2%; mean, 3 SLNs per patient) had stained SLNs as compared to only 33/48 (68.8%) of patients with T3 tumors (mean, 3.3 SLNs per patient). The positive predictive value of the SLN mapping was 100%, the negative predictive value was 76.9%, and sensitivity was 85.4%.ConclusionWhile in T1 and T2 tumors sentinel node mapping may be of assistance in the decision-making process regarding the extent of lymphadenectomy (sensitivity, 100%; negative predictive value, 90%-100%), SLN mapping in patients with T3 tumors will be misleading in a third of the patients and should not be attempted.

A comparative study on two different pathological methods to retrieve lymph nodes following gastrectomy

BACKGROUND The number of lymph nodes harvested during gastrectomy depends on the extension of lymphadenectomy and the method of lymph node retrieval. AIM The objective of this study was to evaluate two methods of lymph node retrieval in specimens of gastric cancer. METHODS The number of lymph nodes was compared using two different techniques. The technique used in the first group was manual dissection following formalin fixation, and the techniques used in the second group was fat-clearing by acetone. RESULTS Both groups were comparable for demographic and pathological variables. The average number of harvested nodes was 19.3 ± 10 for the manual group as compared to 26.1 ± 14 in the acetone group (P = 0.003). The differences in the average number of positive nodes did not reach statistical significance (4.6 compared to 6.9 nodes). CONCLUSION The acetone clearing technique enables the evaluation of a larger number of nodes. An increase, but statistically non significant, number of positive nodes was noted in the acetone group.

Indication for relumpectomy—a useful scoring system in cases of invasive breast cancer†

In two‐thirds of breast cancer patients undergoing reoperation no residual tumor will be found. A scoring system for selection of patients who might benefit from relumpectomy is proposed.

The role of diagnostic laparoscopy in detecting minimal peritoneal metastatic deposits in patients with pancreatic cancer scheduled for curative resection.

Background: Pancreatic cancer (PC) is an aggressive disease usually diagnosed at an advanced stage. Modern computed tomography can define the subgroup of operable patients. However, minimal peritoneal deposits can be undetected even by modern computed tomography protocols. Aim: To diagnose those patients who are not operable because of a peritoneal spread using diagnostic laparoscopy (DL), thus avoiding unnecessary laparotomies. Methods: A retrospective study was conducted on 52 consecutive patients with PC scheduled for curative pancreatic surgery. Results: Out of 52 patients who underwent DL, peritoneal spread was diagnosed in 5 patients and these patients were denied surgery. Laparoscopy did not detect 2 other patients with peritoneal spread. Conclusions: Although the added value of DL in patients with PC is small (around 10% in our series), considering the minimal morbidity and costs attributed to this procedure, we believe that it should be adopted as a routine approach.

Tumor differentiation as related to sentinel lymph node status in gastric cancer

AIM To investigate the influence of tumor grade on sentinel lymph node (SLN) status in patients with gastric cancer (GC). METHODS We retrospectively studied 71 patients with GC who underwent SLN mapping during gastric surgery to evaluate the relationship between SLN status and tumor grade. RESULTS Poorly differentiated tumors were detected in 50/71 patients, while the other 21 patients had moderately differentiated tumors. SLNs were identified in 58/71 patients (82%). In 41 of the 58 patients that were found to have stained nodes (70.7%), the tumor was of the poorly differentiated type (group I), while in the remaining patients with stained nodes 17/58 (29.3%), the tumor was of the moderately differentiated type (group II). Positive SLNs were found in 22/41 patients in group I (53.7%) and in 7/17 patients in group II (41.2%) (P = 0.325). The rate of positivity for the SLNs in the two groups (53.7% vs 41.2%) was not statistically significant (P = 0.514). CONCLUSION Most of our patients were found to have poorly differentiated adenocarcinoma of the stomach and there was no correlation between tumor grade and SLN involvement.

FDG PET-CT evaluation in neurolymphomatosis: imaging characteristics and clinical outcomes

Abstract Neurolymphomatosis (NL) often represents unidentified non-Hodgkin lymphoma relapses. Considering its severity, early detection and treatment are crucial. We outline one hospital’s 18F-FDG-PET-CT imaging findings of NL, along with the patients’ clinical characteristics. Clinical records and imaging findings of 19 NL patients, PET-CT diagnosed, were retrospectively reviewed. Patient data, FDG-PET-CT findings and the presence of coexisting diseases, especially CNS involvement, were documented. Available MRI and clinical data verified the findings. All cases had increased linear FDG uptake along anatomic nerve sites. CTs showed varying degrees of corresponding soft-tissue-thickening. Clinical correlations also contributed to the diagnosis. In 4/19 patients, lymphoma presented with NL, in 15/19 it appeared with disease recurrence/progression. In 9/19, clinical symptoms suggested neural involvement while 10/19 had nonspecific symptoms. Eleven died of lymphoma within 0.9 years of diagnosis despite directed-therapy. Eight, however, survived up to 7.82 years post-diagnosis. Whole-body FDG-PET-CT can assist in early NL diagnosis, possibly enhancing survival.

Lymphocytic Infiltration as a Prognostic Factor in Patients With Colon Cancer.

Host-defense mechanisms may have an important role in predicting the outcome of colorectal cancer patients. We designed our study to evaluate the possible prognostic significance of the presence of lymphocytic infiltration (LI) and subgroups of lymphocytes (CD3 and CD20) in the primary tumors. We randomly selected 195 patients operated for colorectal carcinoma from a larger cohort of 1527 patients with colorectal cancer. Histological slides were blindly reevaluated for the presence of LI that was graded 0 to 3. Immunohistochemical phenotyping of the lymphocytes was performed only for tumors with LI score 3 and included antibodies CD3 and CD20. CD3 and CD20 immunostaining were graded in the same manner as LI. The mean duration of follow-up was 63.8 months. The distribution of patients with colorectal cancer according to LI scores was as follows: score 0, 20/195 (10.2%); score 1, 61/195 (31.3%); score 2, 78/195 (40%); and score 3, 36/195 (18.5%). There was no correlation between any clinicopathological pattern and LI. Score 3 staining for CD3 was more common than for CD20 (64.7% vs 8.8%, P < .0001). Prominent lymphocytic infiltration (score 3) was associated with better disease-free survival (P = .062). Recurrence was diagnosed among 2/22 (9.1%) patients with prominent CD3 staining versus 62/171 (36.2%) of all other patient groups (P = .054) and they correspondingly had better disease-free survival (P = .018). It seems we can identify a group of patients with colorectal cancer who have an excellent prognosis according to a single immunological test unrelated to other known prognostic factors.

Fat necrosis after abdominal surgery: A pitfall in interpretation of FDG-PET/CT

AbstractObjectiveWe describe FDG-PET/CT findings of postoperative fat necrosis in patients following abdominal surgery, and evaluate their changes in size and FDG uptake over time.MethodsFDG-PET/CT scans from January 2007–January 2016 containing the term ‘fat necrosis’ were reviewed. Lesions meeting radiological criteria of fat necrosis in patients with prior abdominal surgery were included.ResultsForty-four patients, 30 males, mean age 68.4 ± 11.0 years. Surgeries: laparotomy (n=37; 84.1 %), laparoscopy (n=3; 6.8 %), unknown (n=4; 9.1 %). CTs of all lesions included hyperdense well-defined rims surrounding a heterogeneous fatty core. Sites: peritoneum (n=34; 77 %), omental fat (n=19; 43 %), subcutaneous fat (n=8; 18 %), retroperitoneum (n=2; 5 %). Mean lesion long axis: 33.6±24.9 mm (range: 13.0–140.0). Mean SUVmax: 2.6±1.1 (range: 0.6–5.1). On serial CTs (n=34), lesions decreased in size (p=0.022). Serial FDG-PET/CT (n=24) showed no significant change in FDG-avidity (p=0.110). Mean SUVmax did not correlate with time from surgery (p=0.558) or lesion size (p=0.259).ConclusionPostsurgical fat necrosis demonstrated characteristic CT features and may demonstrate increased FDG uptake. However, follow-up of subsequent imaging scans showed no increases in size or FDG-avidity. Awareness of this entity is important to avoid misinterpretation of findings as recurrent cancer.Key Points• Postsurgical fat necrosis may mimic cancer in FDG-PET/CT. • Follow-up of fat necrosis showed no increase in FDG intensity. • CT follow-up showed a decrease in lesion size. • FDG uptake did not correlate with time lapsed from surgery.

Incidental detection of elastofibroma dorsi on PET-CT: initial findings and changes in tumor size and standardized uptake value on serial scans.

ObjectiveWe describe changes in elastofibroma dorsi (EFD) as observed in serial fluorine-18 fluorodeoxyglucose (18F-FDG) PET-computed tomography (CT) imaging studies. Materials and methods18F-FDG PET-CT studies carried out between January 2006 and January 2015 at a single institution were reviewed by an experienced radiologist and nuclear medicine specialist. When available, previous or subsequent imaging studies were reviewed to evaluate changes in EFD. ResultsOf 28 500 PET-CT studies carried out, EFD was identified in 68 from 20 patients (mean age 67.1±10.2 years; 14 women). Five patients had unilateral lesions and 15 patients had bilateral lesions. Eighteen patients had oncologic diseases. The mean size of EFD at first presentation was 13.95±5.90 mm and the mean homogeneous low-grade 18F-FDG uptake was maximum standardized uptake value (SUVmax) 2.24±0.95. One or more additional CT scans were performed in 17 patients; the mean interval between the first and last scans was 57.4±39.2 months. EFD was unchanged in size in 7/17 (41%) and showed slow growth in 10/17, reaching a mean size of 19 mm. The mean monthly growth rate was 0.1±0.10 mm. PET imaging in 11 patients showed a mean first SUVmax of 2.08±1.17 and a mean last SUVmax of 2.74±1.05 after a mean of 47.5±31.5 months (P=0.63). ConclusionSerial PET-CT studies may show a stable or slowly enlarging mass on a CT scan without changes in 18F-FDG uptake on PET imaging. Familiarity with CT appearances and 18F-FDG uptake of EFD are important for correct interpretation of 18F-FDG PET-CT studies.

Focal fluorine-18 fluorodeoxyglucose-avid parotid findings in patients with lung cancer: prevalence and characteristics.

ObjectiveCorrect interpretation of incidental tumors is important to plan an appropriate treatment. We assessed the incidence and imaging characteristics of fluorine-18 fluorodeoxyglucose (18F-FDG)-avid focal parotid findings (FPFs) in patients with lung cancer. Patients and methodsFPFs in PET-computed tomography reports of cancer patients were searched. Those with known parotid malignancies, lymphoma, and diffuse 18F-FDG uptake in the entire parotid gland were not included in the analysis. ResultsFPFs were detected in 38/3120 cancer patients (1.23%), observed as a soft tissue mass with a mean diameter 1.6±0.5 cm (range 0.8–2.7 cm) and a mean maximum standardized uptake value of 7.7±3.7 (range 2.5–17.8). FPFs were observed in 23/604 (3.8%) patients with lung cancer, compared with 6/1366 (0.4%) with breast cancer and 5/842 (0.6%) with gastrointestinal malignancies. We assessed FPFs appearances in 23 patients with lung cancer (18 men, mean age 72.8±9.2); 20 (87%) were current or past smokers. There was no correlation between the stage or histopathological type of the lung cancer and the prevalence of parotid lesions. In four patients with histopathology, no malignancy was detected. For an additional 11 patients with available imaging and clinical follow-up (mean follow-up 15.5±13.5 months, range 3–42 months), FPFs were consistent with benign lesions. ConclusionFPFs were more prevalent among patients with lung cancer than in patients with other malignancies. As 18F-FDG avidity was moderate to high, FPFs may mimic distant metastases. It is important to consider FPFs in the interpretation of a focal parotid lesion as misinterpretation may result in denial of appropriate therapy.