Evaluation of sentinel lymph node size and shape as a predictor of occult metastasis in patients with squamous cell carcinoma of the oral cavity

Sentinel lymph node mapping using ICG fluorescence and cone beam CT - a feasibility study in a rabbit model of oral cancer

BACKGROUND

Current sentinel lymph node biopsy (SLNB) techniques, including use of radioisotopes, have disadvantages including the use of a radioactive tracer. Indocyanine green (ICG) based near-infrared (NIR) fluorescence imaging and cone beam CT (CBCT) have advantages for intraoperative use. However, limited literature exists regarding their use in head and neck cancer SLNB.

METHODS

This was a prospective, non-randomized study using a rabbit oral cavity VX2 squamous cell carcinoma model (n = 10) which develops lymph node metastasis. Pre-operatively, images were acquired by MicroCT. During surgery, CBCT and NIR fluorescence imaging of ICG was used to map and guide the SLNB resection.

RESULTS

Intraoperative use of ICG to guide fluorescence resection resulted in identification of all lymph nodes identified by pre-operative CT. CBCT was useful for near real time intraoperative imaging and 3D reconstruction.

CONCLUSIONS

This pre-clinical study further demonstrates the technical feasibility, limitations and advantages of intraoperative NIR-guided ICG imaging for SLN identification as a complementary method during head and neck surgery.

Pathological nodal staging score for rectal cancer patients treated with radical surgery with or without neoadjuvant therapy: a postoperative decision tool

Background

Lymph node status can predict the prognosis of patients with rectal cancer treated with surgery. Thus, we sought to establish a standard for the minimum number of lymph nodes (LNs) examined in patients with rectal cancer by evaluating the probability that pathologically negative LNs prove positive during surgery.

Patients and methods

We extracted information of 31,853 patients with stage I–III rectal carcinoma registered between 2004 and 2013 from the Surveillance, Epidemiology, and End Results database and divided them into two groups: the first group was SURG, including patients receiving surgery directly and the other group was NEO, encompassing those underwent neo-adjuvant therapy. Using a beta-binomial model, we developed nodal staging score (NSS) based on pT/ypT stage and the number of LNs retrieved.

Results

In both cohorts, the false-negative rate was estimated to be 16% when 12 LNs were examined, but it dropped to 10% when 20 LNs were evaluated. In the SURG cohort, to rule out 90% possibility of false staging, 3, 7, 28, and 32 LNs would be necessarily examined in patients with pT1–4 disease, respectively. While in the NEO cohort, 4, 7, 12, and 16 LNs would be included for examination in patients with ypT1–4 disease to guarantee an NSS of 90%.

Conclusion

By determining whether a rectal cancer patient with negative LNs was appropriately staged, the NSS model we developed in this study may assist in tailoring postoperative management.

Kikuchi-Fujimoto disease in the regional lymph nodes with node metastasis in a patient with tongue cancer: A case report and literature review

Kikuchi-Fujimoto disease (KFD), also known as histiocytic necrotizing lymphadenitis, is a rare self-limiting disorder typically affecting the cervical lymph nodes (LNs), which is often misdiagnosed as other LN-associated diseases. KFD frequently presents with necrotic lesions and recurrences, which are also features of metastatic LNs. Clinicians may thus suspect LN metastasis when they encounter ipsilateral cervical lymphadenopathy in a patient with head and neck cancer. The present study reports the case of a 48-year-old man with tongue cancer and KFD affecting the right edge of his tongue and ipsilateral cervical LNs. LN metastasis was initially suspected, but pathological examination of the dissected LNs revealed one necrotic metastatic lesion and two necrotic KFD lesions. Ipsilateral cervical lymphadenopathy recurred 6 years after the initial surgery, and it was not possible to differentiate clinically between a second primary tumor and recurrent KFD prior to treatment. To the best of our knowledge, this is the first reported case of simultaneous tongue cancer, regional LN metastasis and KFD. This highlights the requirement to consider KFD in the event of LNs with necrotic lesions but no cancerous cells. A combination of clinical and pathological approaches may aid in the diagnosis of KFD, in addition to ruling out LN metastasis in initial and recurrent lymphadenopathies. The present study indicate that a diagnosis of KFD should be considered in patients with head and neck cancer that exhibit necrotic LNs lacking cancerous cells. This is important, as misdiagnosis of KFD as LN metastasis may lead to unnecessary adjuvant therapy.

Sentinel lymph node biopsy for early oral cancers: Westmead Hospital experience

BACKGROUND

Sentinel lymph node biopsy (SLNB) has become an alternative option to elective neck dissection (END) for early oral cavity squamous cell carcinoma (OCSCC) outside of Australia. We sought to assess the technical feasibility of SLNB and validate its accuracy against that of END in an Australian setting.

METHODS

We performed a prospective cohort study consisting of 30 consecutive patients with cT_1-2 N₀ OCSCC referred to the Head and Neck Cancer Service, Westmead Hospital, Sydney, between 2011 and 2014. All patients underwent SLNB followed by immediate selective neck dissection (levels I-III).

RESULTS

A total of 30 patients were diagnosed with an early clinically node-negative OCSCC (seven cT1 and 23 cT2), with the majority located on the oral tongue. A median of three (range: 1-14) sentinel nodes were identified on lymphoscintigraphy, and all sentinel nodes were successfully retrieved, with 50% having a pathologically positive sentinel node. No false-negative sentinel nodes were identified using selective neck dissection as the gold standard. The negative predictive value (NPV) of SLNB was 100%, with 40% having a sentinel node identified outside the field of planned neck dissection on lymphoscintigraphy. Of these, one patient had a positive sentinel node outside of the ipsilateral supraomohyoid neck dissection template.

CONCLUSION

SLNB for early OCSCC is technically feasible in an Australian setting. It has a high NPV and can potentially identify at-risk lymphatic basins outside the traditional selective neck dissection levels even in well-lateralized lesions.