Treatment of Localized Amyloid Light Chain Amyloidosis With External Beam Radiation Therapy

PURPOSE

Localized amyloidosis is a condition characterized by deposits of fibrillary proteins confined to a single organ. The most common subtype is amyloid light chain amyloidosis, which is caused by secretion of amyloidogenic light chain by a monoclonal population of plasma cells. We present a review and discussion of the literature in the context of a case presentation of localized amyloid light chain amyloidosis of the nasopharynx treated with radiation alone.

METHODS AND MATERIALS

We reviewed literature relevant to this topic from 1970 to the present. Relevant studies, reports, and articles were summarized in table form.

RESULTS

Surgical resection has historically been the primary therapeutic modality for these patients, with radiation being reserved for recurrent lesions or for those unfit for surgery. Although the data are limited to small retrospective series, radiation has been shown to provide good control with mild toxicity that is as good as or better than surgery. Doses range from 20 to 45 Gy, conventionally fractionated. There is no known risk of progression to systemic disease without local therapy.

CONCLUSIONS

We recommend local therapy for symptomatic patients after systemic disease has been excluded. We generally recommend radiation in the setting of recurrent lesions, unacceptable toxicity with surgery, poor surgical candidates, and as the initial modality in select patients (elderly individuals with bothersome but nonobstructive lesions).

Localised laryngotracheal amyloidosis: a differential diagnosis not to forget

We present a case of multifocal laryngotracheal amyloidosis (LTA) in a 43-year-old man with persistent and progressive dysphonia and dyspnoea, and a first inconclusive histology. Although laryngeal amyloidosis accounts for fewer than 1% of all benign laryngeal tumours, it is in fact the most common site of amyloid deposition in the head, neck and respiratory tract. The clinical scenario is non-specific and diagnosis depends on a high degree of suspicion and on histology. Imaging is useful in mapping lesions, which are often more extensive than they appear during laryngoscopy. Despite being a benign entity, the prognosis is variable with a high-rate and long-latency recurrences, requiring long-term follow-up.

Long-term Follow-up After Radiation Therapy for Laryngeal Amyloidosis

OBJECTIVES

Laryngeal amyloidosis (LA) is a rare disease characterized by extracellular protein deposition within the larynx. Treatment is difficult due to the frequently submucosal and multifocal nature of disease. The mainstay of treatment is surgical resection; however, recurrence rates are high. Recently, use of radiotherapy (RT), either alone or postoperatively, for LA has been adapted from the management of extramedullary plasmacytoma and has been shown to provide local disease control. Here, we describe the experience with adjuvant RT for LA at our center.

STUDY DESIGN

Retrospective case series.

METHODS

Retrospective study of patients with amyloidosis of the larynx, with or without other disease sites, seen at a tertiary academic center between 2011 and 2019. Outcomes included disease characteristics, recurrence rates, treatment modalities, and pre- and posttreatment voice handicap index (VHI)-10.

RESULTS

Ten patients met eligibility criteria. Mean follow-up time for all patients was 62.0 ± 41.0 months; mean follow-up time after last treatment was 51 ± 55 months. All but one patient underwent surgical resection of disease. Seven patients underwent subsequent RT. Of these seven, six underwent RT at our institution; five received a dose of 45 Gray (Gy); and one received a dose of 20 Gy. All seven completed RT without toxicity-related interruption. Patients undergoing RT underwent 2.1 ± 1.3 surgical procedures prior to RT; no patients required surgery after RT. Mean pretreatment VHI-10 was 22.9 ± 8.1; mean posttreatment VHI-10 was 12.9 ± 13.3.

CONCLUSION

RT after surgery for LA can provide good local control without unacceptable toxicity and may decrease the need for further surgery.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:1810-1815, 2021.

Laryngeal amyloidosis: diagnosis, pathophysiology and management

Background:

Laryngeal amyloidosis represents approximately 1 per cent of all benign laryngeal lesions, and can cause variable symptoms depending on anatomical location and size. Treatment ranges from observation through to endoscopic microsurgery, laser excision and laryngectomy.

Objectives:

To highlight the diversity of presentations, increase awareness of paediatric amyloidosis and update the reader on current management.

Case series:

Five cases are illustrated. Four adult patients were female, and the one child, the second youngest in the literature, was male. Amyloid deposits were identified in all laryngeal areas, including the supraglottis, glottis and subglottis. Treatment consisted of balloon dilatation, endoscopic excision, laser cruciate incision, and resection with carbon dioxide laser, a microdebrider and coblation wands.

Conclusion:

Laryngeal amyloidosis remains a rare and clinically challenging condition. Diagnosis should be considered for unusual appearing submucosal laryngeal lesions. Treatment of this disease needs to be evaluated on a case-by-case basis and managed within an appropriate multidisciplinary team.